Molecular in vitro diagnostic examinations - Specifications for pre-examination processes for circulating tumor cells (CTCs) in venous whole blood - Part 1: Isolated RNA

This document gives guidelines on the handling, storage, processing and documentation of venous whole blood specimens intended for the examination of human cellular RNA isolated from Circulating Tumor Cells (CTCs) during the pre-examination phase before a molecular examination is performed.
This document is applicable to molecular in vitro diagnostic examinations including laboratory developed tests performed by medical laboratories. It is also intended to be used by laboratory customers, in vitro diagnostics developers and manufacturers, biobanks, institutions and commercial organizations performing biomedical research, and regulatory authorities.
This document does not cover the isolation of cellular RNA directly from venous whole blood containing CTCs. This is covered in EN ISO 20186-1.
This document does not cover the isolation of specific blood cells and subsequent isolation of cellular RNA therefrom.
RNA in pathogens present in blood is not covered by this document.
NOTE International, national or regional regulations or requirements can also apply to specific topics covered in this document.

Molekularanalytische in-vitro-diagnostische Verfahren - Spezifikationen für präanalytische Prozesse für zirkulierende Tumorzellen (CTC) in venösen Vollblutproben - Teil 1: Isolierte RNA

Dieses Dokument gibt Empfehlungen zur Handhabung, Lagerung, Verarbeitung und Dokumentation von Proben venösen Vollbluts, die für die Untersuchung der aus zirkulierenden Tumorzellen (CTCs) isolierten RNA vorgesehen sind, während der präanalytischen Phase vor der Durchführung einer molekularen Analyse.
Dieses Dokument ist anwendbar auf molekulare in vitro diagnostische Untersuchungen, die in medizinischen Laboratorien durchgeführt werden, einschließlich vom Laboratorium selbst entwickelter Verfahren. Es ist darüber hinaus für die Verwendung durch Kunden von Laboratorien, Entwickler und Hersteller von In vitro Diagnostika, durch Biobanken, Institutionen und kommerzielle Organisationen, die biomedizinische Forschungen durchführen, sowie durch Arzneimittelagenturen bestimmt.
Dieses Dokument behandelt nicht die direkte Isolierung von zellulärer RNA aus venösen Vollblutproben, die CTCs enthalten. Dies wird in EN ISO 20186 1, Molekularanalytische in vitro diagnostische Verfahren — Spezifikationen für präanalytische Prozesse für venöse Vollblutproben — Teil 1: Isolierte zelluläre RNA behandelt.
Dieses Dokument behandelt nicht die Isolierung von bestimmten weißen Blutzellen (Leukozyten) und die anschließende Isolierung von zellulärer RNA aus diesen Zellen.
Dieses Dokument behandelt auch nicht die Anforderungen an den präanalytischen Arbeitsablauf zur Kryokonservierung und Kultivierung lebensfähiger CTCs.
ANMERKUNG 1 Die in diesem Dokument dargelegten Anforderungen können auch auf andere zirkulierende Zellen (z. B. fetale Zellen) angewendet werden.
ANMERKUNG 2 Internationale, nationale oder regionale Regelungen bzw. Anforderungen können ebenfalls für bestimmte Themen in diesem Dokument gelten.

Analyses de diagnostic moléculaire in vitro - Spécifications relatives aux processus préanalytiques pour les cellules tumorales circulantes (CTCs) dans le sang total veineux - Partie 1 : ARN extrait

Molekularne diagnostične preiskave in vitro - Specifikacije za predpreiskovalne procese za cirkulirajoče tumorske celice (CTC) v venski polni krvi - 1. del: Izolirana RNK

Ta dokument podaja smernice glede obravnave, shranjevanja, obdelave in dokumentiranja vzorcev venske polne krvi, namenjenih za analizo človeške celične RNK, izolirane iz cirkulirajočih tumorskih celic (CTC) med predpreiskovalno fazo, preden se izvede molekularna preiskava. Ta dokument se uporablja za molekularne diagnostične preiskave in vitro, vključno z laboratorijsko razvitimi preskusi, ki jih izvajajo v medicinskih laboratorijih. Namenjen je tudi temu, da ga uporabljajo laboratorijske stranke, razvijalci in proizvajalci diagnostike in vitro, biobanke, institucije in komercialne organizacije, ki izvajajo biomedicinske raziskave, ter regulativni organi. Ta dokument ne zajema izolacije celične RNK neposredno iz venske polne krvi, ki vsebuje cirkulirajoče tumorske celice. To je zajeto v standardu EN ISO 20186-1. Ta dokument ne zajema izolacije določenih krvnih celic in nadaljnje izolacije celične RNK iz njih. RNK v patogenih v krvi ni zajeta v tem dokumentu.
OPOMBA: Za določene teme, ki so zajete v tem dokumentu, lahko veljajo tudi mednarodni, nacionalni ali regionalni predpisi ali zahteve.

General Information

Status
Published
Publication Date
21-Jan-2020
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Due Date
22-Jan-2020
Completion Date
22-Jan-2020

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SLOVENSKI STANDARD
SIST-TS CEN/TS 17390-1:2020
01-marec-2020
Molekularne diagnostične preiskave in vitro - Specifikacije za predpreiskovalne

procese za cirkulirajoče tumorske celice (CTC) v venski polni krvi - 1. del: Izolirana

RNK

Molecular in vitro diagnostic examinations - Specifications for pre-examination processes

for circulating tumor cells (CTCs) in venous whole blood - Part 1: Isolated RNA
Molekularanalytische in-vitro-diagnostische Verfahren - Spezifikationen für

präanalytische Prozesse für zirkulierende Tumorzellen (CTC) in venösen Vollblutproben

- Teil 1: Isolierte RNA

Analyses de diagnostic moléculaire in vitro - Spécifications relatives aux processus

préanalytiques pour les cellules tumorales circulantes (CTCs) dans le sang total veineux

- Partie 1 : ARN extrait
Ta slovenski standard je istoveten z: CEN/TS 17390-1:2020
ICS:
11.100.10 Diagnostični preskusni In vitro diagnostic test
sistemi in vitro systems
SIST-TS CEN/TS 17390-1:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TS CEN/TS 17390-1:2020
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SIST-TS CEN/TS 17390-1:2020
CEN/TS 17390-1
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
January 2020
TECHNISCHE SPEZIFIKATION
ICS 11.100.10
English Version
Molecular in vitro diagnostic examinations - Specifications
for pre-examination processes for circulating tumor cells
(CTCs) in venous whole blood - Part 1: Isolated RNA

Analyses de diagnostic moléculaire in vitro - Molekularanalytische in-vitro-diagnostische Verfahren

Spécifications relatives aux processus préanalytiques - Spezifikationen für präanalytische Prozesse für

pour les cellules tumorales circulantes (CTCs) dans le zirkulierende Tumorzellen (CTC) in venösen

sang total veineux - Partie 1 : ARN extrait Vollblutproben - Teil 1: Isolierte RNA

This Technical Specification (CEN/TS) was approved by CEN on 27 October 2019 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to

submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS

available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in

parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17390-1:2020 E

worldwide for CEN national Members.
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Contents Page

European foreword ....................................................................................................................................................... 3

Introduction .................................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 5

4 General considerations .............................................................................................................................. 10

5 Outside the laboratory ............................................................................................................................... 11

5.1 Specimen collection ..................................................................................................................................... 11

5.2 Transport requirements............................................................................................................................ 13

6 Inside the laboratory .................................................................................................................................. 14

6.1 Specimen reception ..................................................................................................................................... 14

6.2 Storage requirements for the venous whole blood specimen ..................................................... 14

6.3 Enrichment of CTCs ..................................................................................................................................... 14

6.4 Quality of enriched CTCs............................................................................................................................ 15

6.5 Storage of enriched CTCs ........................................................................................................................... 15

6.6 Isolation of CTCs ........................................................................................................................................... 15

6.7 Processing of isolated CTCs ...................................................................................................................... 16

6.8 Isolation of RNA from an enriched CTC sample................................................................................. 17

6.9 Quantity and quality assessment of isolated RNA from enriched or isolated CTCs ............. 18

6.10 Storage of isolated RNA from enriched CTCs ..................................................................................... 18

Annex A (informative) Decision guideline for critical steps of the CTC pre-analytical

workflow for RNA isolation ...................................................................................................................... 20

Bibliography ................................................................................................................................................................. 23

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European foreword

This document (CEN/TS 17390-1:2020) has been prepared by Technical Committee CEN/TC 140 “In

vitro diagnostic medical devices”, the secretariat of which is held by DIN.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

CEN/TS 17390 consists of the following parts, under the general title Molecular in vitro diagnostic

examinations — Specifications for pre-examination processes for Circulating Tumor Cells (CTCs) in venous

whole blood:
— Part 1: Isolated RNA
— Part 2: Isolated DNA
— Part 3: Preparations for analytical CTC staining

According to the CEN/CENELEC Internal Regulations, the national standards organisations of the

following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria,

Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,

Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of

North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the

United Kingdom.
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Introduction

Solid tumours release cells and bioanalytes into blood and other body fluids. This has opened the option

of minimally-invasive tumour detection, diagnosis and characterization from venous whole blood

(liquid biopsies). Liquid biopsies are expected to enable earlier detection and diagnosis of cancers and

advance personalized patient treatment. These applications have become one of the fastest growing

segments of the entire diagnostic market.

Circulating tumour cells (CTCs) in venous whole blood reflect the disease complexity that evolves

during tumour progression, with distinct genetic, epigenetic and expression features. Besides the

prognostic role of CTC identification and/or enumeration in cancer progression, CTC molecular

characterization can improve e.g. disease outcome prediction, therapeutic guidance and post-treatment

monitoring of the patient.

CTCs are now considered as a surrogate of tumour tissue in cancer early development, progression and

metastatic phase.

Molecular characterization of CTCs can provide for example a strategy for monitoring cancer genotypes

during systemic therapies [1], identification of mechanisms of disease progression, identification of

novel targets for treatment [2] and to select targeted therapies. Moreover, CTC single-cell sequencing is

emerging as an important tool for tumour genomic heterogeneity analysis [3] [4] [5].

CTCs are fragile and tend to degrade within a few hours when collected in conventional blood collection

tubes, e.g. EDTA containing tubes, without dedicated CTC stabilizers. CTCs are extremely rare, especially

in early disease, e.g. less than 10 cells per 10 ml of blood, representing a ratio of approx. 1:10 CTCs to

white blood cells (WBCs). This low ratio represents a significant challenge to CTC enrichment required

for examination.

RNA profiles of CTCs resemble gene expression profiles of tumours. For RNA profile analysis, measures

need to be taken to get rid of the WBCs in order to obtain sufficiently enriched CTC-specific RNA.

RNA profiles can change significantly after blood collection, during CTC enrichment and isolation.

Therefore, special measures need to be taken to obtain good quality CTC samples and good quality

isolated RNA for gene expression analysis [4] [6].

Consequently, standardization of all steps of the pre-examination process is required. This includes

blood collection and stabilization, transport, storage, CTC enrichment, CTC isolation (if required), and

RNA isolation. A decision guideline for the critical steps of the CTC pre-analytical workflow for RNA

isolation is provided in Annex A.

This document describes special measures that need to be taken to obtain appropriate quality and

quantity of RNA from CTC containing blood specimens for subsequent examination.
In this document, the following verbal forms are used:
— “shall” indicates a requirement;
— “should” indicates a recommendation;
— “may” indicates a permission;
— “can” indicates a possibility or a capability.
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1 Scope

This document gives guidelines on the handling, storage, processing and documentation of human

venous whole blood specimens intended for the examination of RNA isolated from circulating tumour

cells (CTCs) during the pre-examination phase before a molecular examination is performed.

This document is applicable to molecular in vitro diagnostic examinations including laboratory

developed tests performed by medical laboratories. It is also intended to be used by laboratory

customers, in vitro diagnostics developers and manufacturers, biobanks, institutions and commercial

organizations performing biomedical research, and regulatory authorities.

This document does not cover the isolation of cellular RNA directly from venous whole blood containing

CTCs. This is covered in EN ISO 20186-1, Molecular in vitro diagnostic examinations - Specifications for

pre-examination processes for venous whole blood – Part 1: Isolated cellular RNA.

This document does not cover the isolation of specific white blood cells and subsequent isolation of

cellular RNA therefrom.

This document does not cover pre-analytical workflow requirements for viable CTC cryopreservation

and culturing.

NOTE 1 The requirements given in this document can also be applied to other circulating rare cells (e.g. fetal

cells).

NOTE 2 International, national or regional regulations or requirements can also apply to specific topics

covered in this document.
2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

EN ISO 15189:2012, Medical laboratories - Requirements for quality and competence (ISO 15189:2012,

Corrected version 2014-08-15)
ISO 15190, Medical laboratories — Requirements for safety
3 Terms and definitions

For the purposes of this document, the terms and definitions given in EN ISO 15189 and the following

terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1
aliquot

portion of a larger amount of homogenous material, assumed to be taken with negligible sampling error

Note 1 to entry: The term is usually applied to fluids. Tissues are heterogeneous and therefore cannot be

aliquoted.
Note 2 to entry: The definition is derived from References [7], [8] and [9].
[SOURCE: EN ISO 20166-3:2019, 3.1]
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3.2
ambient temperature
unregulated temperature of the surrounding air
[SOURCE: EN ISO 20166-3:2019, 3.2]
3.3
analyte
component represented in the name of a measurable quantity
[SOURCE: EN ISO 17511:2003, 3.2, modified — EXAMPLE has been removed.]
3.4
analytical test performance

accuracy, precision, specificity and sensitivity of a test to measure the analyte of interest

Note 1 to entry: Other test performance characteristics such as robustness, repeatability can apply as well.

[SOURCE: EN ISO 20184-1:2018, 3.4]
3.5
blood collection set

intravenous device specialized for venipuncture consisting of a stainless steel bevelled needle and tube

(tubing) with attached plastic wings and fitting connector

Note 1 to entry: The connector attaches to an additional blood collection device, e.g. a blood collection tube.

3.6
blood collection tube

tube used for blood collection, usually in a vacuum which forces blood from the vein through the needle

and into the tube
3.7
backflow
flow of a liquid opposite to the usual or desired direction
3.8
circulating tumor cells
CTCs

cells present in blood, originating from a primary and/or metastatic site of a tumor

3.9
CTC enrichment
any method that is able to increase the ratio of CTCs to other cells
3.10
CTC isolation
any method resulting in a sample containing CTCs without any other cell types
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3.11
diagnosis

identification of a disease from its signs and symptoms, where the diagnostic process can involve

examinations and tests for classification of an individual's condition into separate and distinct

categories or subclasses that allow medical decisions about treatment and prognosis to be made

[SOURCE: EN ISO 20184-1:2018, 3.6]
3.12
DNase
deoxyribonuclease
enzyme that catalyzes the degradation of DNA into smaller components
[SOURCE: EN ISO 20186-1:2019, 3.11]
3.13
examination
analytical test

set of operations having the object of determining the value or characteristics of a property

Note 1 to entry: Processes that start with the isolated analyte and include all kinds of parameter testing or

chemical manipulation for quantitative or qualitative examination.

[SOURCE: EN ISO 15189:2012, 3.7, modified — Notes to entry 1 to 3 have been removed, Note 1 to

entry has been added and “analytical test” has been added as a preferred term.]
3.14
examination performance
analytical test performance
analytical performance
ability of an examination procedure to measure or detect a particular analyte

Note 1 to entry: Analytical performance is determined from analytical performance studies used to assess the

ability of an in vitro diagnostic examination procedure to measure or detect a particular analyte.

Note 2 to entry: Analytical performance includes such characteristics as analytical sensitivity, detection limit,

analytical specificity (interference and cross-reactivity), trueness, precision and linearity.

[SOURCE: ISO/TS 17822-1:2014, 3.2, modified — “analytical test performance” and “analytical

performance” have been added as preferred terms.]
3.15
examination manufacturer
analytical test manufacturer
group or company that provides the specific analytical test
3.16
needle holder

barrel used in routine venipuncture procedures to hold the blood collection tube in place and to protect

the phlebotomist from direct contact with blood
[SOURCE: EN ISO 20186-1:2019, 3.18]
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3.17
pre-examination processes
preanalytical phase
preanalytical workflow

processes that start, in chronological order, from the clinician’s request and include the examination

request, preparation and identification of the patient, collection of the primary sample(s),

transportation to and within the medical or pathology laboratory, isolation of analytes, and end when

the analytical examination begins

Note 1 to entry: The pre-examination phase includes preparative processes that influence the outcome of the

intended examination.

[SOURCE: EN ISO 15189:2012, 3.15, modified — “pre-analytical workflow” has been added as a

preferred term, Note 1 to entry has been added and the definition has been extended.]

3.18
primary sample
specimen

discrete portion of a body fluid, breath, hair or tissue taken for examination, study or analysis of one or

more quantities or properties assumed to apply for the whole

[SOURCE: EN ISO 15189:2012, 3.16, modified — Notes to entry 1 to 3 have been removed.]

3.19
proficiency testing

evaluation of participant performance against pre-established criteria by means of inter-laboratory

comparisons

[SOURCE: EN ISO/IEC 17043:2010, 3.7, modified — Notes to entry 1 to 3 have been removed.]

3.20
RNA
ribonucleic acid

polymer of ribonucleotides occurring in a double-stranded or single-stranded form

[SOURCE: EN ISO 22174:2005, 3.1.3]
3.21
RNA proficiency testing program
proficiency testing for RNA based examinations
3.22
RNA profile

amounts of different RNA molecules present in a specimen or sample, that can be measured in the

absence of any losses, inhibition and interference
3.23
RNase
ribonuclease
enzyme that catalyzes the degradation of RNA into smaller components
[SOURCE: EN ISO 20186-1:2019, 3.24]
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3.24
room temperature
for the purposes of this document, temperature in the range of 18 °C to 25 °C
Note 1 to entry: Local or national regulations can have different definitions.
3.25
sample
one or more parts taken from a primary sample
[SOURCE: EN ISO 15189:2012, 3.24, modified — EXAMPLE has been removed.]
3.26
stability

ability of a sample material, when stored under specified conditions, to maintain a stated property value

within specified limits for a specified period of time
Note 1 to entry: The analyte for the purpose of this document is RNA.

[SOURCE: ISO Guide 30:2015, 2.1.15, modified — The words “reference material” were replaced by

“sample material”.]
3.27
storage

prolonged interruption of the preanalytical workflow of a sample or analyte respectively, or of their

derivatives e.g., stained sections or tissue blocks, under appropriate conditions in order to preserve

their properties

Note 1 to entry: Long-term storage typically occurs in laboratory archives or in biobanks.

[SOURCE: EN ISO 20166-3:2019, 3.24]
3.28
validation

confirmation, throughout the provision of objective evidence, that the requirements for a specific

intended use or application have been fulfilled

Note 1 to entry: The term “validated” is used to designate the corresponding status.

[SOURCE: EN ISO 9000:2015, 3.8.13, modified — Notes to entry 1 to 3 have been removed.]

3.29
verification

confirmation, through provision of objective evidence, that specified requirements have been fulfilled

Note 1 to entry: The term “verified” is used to designate the corresponding status.

Note 2 to entry: Confirmation can comprise activities such as:
— performing alternative calculations,

— comparing a new design specification with a similar proven design specification,

— undertaking tests and demonstrations, and
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— reviewing documents prior to issue.

[SOURCE: EN ISO 9000:2015, 3.8.12, modified — Notes to entry 1 and 2 have been removed.]

3.30
workflow
series of activities necessary to complete a task
[SOURCE: EN ISO 20166-3:2019, 3.29]
4 General considerations

For general statements on medical laboratory quality management systems and in particular on

specimen collection and handling (including avoidance of cross contaminations), see

EN ISO 15189:2012, 4.2, 5.4.4, or EN ISO/IEC 17020:2012, 7.2 and 8. The requirements on laboratory

equipment, reagents, and consumables according to EN ISO 15189:2012, 5.3 shall be followed;

EN ISO 15189:2012, 5.5.1.2 and 5.5.1.3 and EN ISO/IEC 17020:2012, 6.2 can also apply.

All steps of a diagnostic workflow can influence the final analytical test result. Thus, the entire workflow

including biomolecule stability and specimen and/or sample storage conditions shall be verified and

validated. Workflow steps which cannot always be controlled shall be documented. A risk assessment of

non-controllable workflow steps including their potential impact on the analytical test performance

shall be performed and mitigation measures shall be established to enable the required analytical test

performance.

NOTE CTCs RNA profiles can change significantly after blood collection, e.g. by gene induction, gene down

regulation, RNA degradation [10].

Before or during the design of an examination, it should be investigated and ensured that the specific

RNA profile/s intended to be analysed is/are not compromised in a manner impacting the examination

performance.

CTC analysis usually involves a CTC enrichment step (e.g. by size immunomagnetic-, or microfluidic-

based approaches) prior to RNA isolation. Depending on the requirements of the intended RNA

examination, enriched CTCs can undergo additional steps such as staining and counting for further

characterization. Additionally, the examination can require the isolation of CTCs from the enriched

sample containing an unknown number of CTCs.

Due to the complexity of the pre-analytical workflow, appropriate measures shall be taken to obtain

suitable quantity and quality of enriched CTC RNA.

Safety regulations on specimen transport and handling shall be considered (see EN ISO 15189:2012,

5.2.3 and 5.4.5 and ISO 15190).

During the whole pre-examination process, precautions shall be taken to avoid cross contamination

between different specimens/samples, e.g. by using single-use material whenever feasible or

appropriate cleaning procedures between processing of different specimens/samples.

If a commercial product is not used in accordance with the manufacturer's instructions, responsibility

for its use and performance lies with the user.
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5 Outside the laboratory
5.1 Specimen collection
5.1.1 Information about the specimen donor/patient

The documentation shall include the ID of the specimen donor/patient, which can be in the form of a

code.
The documentation should include, but is not limited to:

a) the relevant health status of the specimen donor/patient (e.g. healthy, disease type, concomitant

disease, demographics (e.g. age and gender));

b) the information about medical treatment and special treatment prior to blood collection;

c) the type and purpose of the proposed examination requested;
d) the appropriate consent from the specimen donor/patient.
See also EN ISO 15189:2012, 5.4.4.
5.1.2 Selection of the venous whole blood collection tube by the laboratory

Due to the low number of CTCs, a high recovery rate is required during enrichment. This can be

hampered by the potential instability of CTCs during transport and storage, leading to a reduction of the

CTC number in the specimen or reduced compatibility with the enrichment system [11]. Also gene

expression profile can change within minutes after blood collection.

Therefore, venous whole blood should be collected in appropriate collection tubes with stabilizers

maintaining the integrity of the CTCs and the CTCs RNA profile (CTC/RNA stabilizer).

Where the CTC examination manufacturer requires usage of a dedicated blood collection tube, this shall

be used. Where the CTC examination manufacturer does not specify a dedicated blood collection tube,

but the CTC isolation manufacturer does, this shall be used.

Where requirements on selecting a dedicated blood collection tube are neither available from the CTC

examination manufacturer nor from the CTC isolation manufacturer, the CTC enrichment

manufacturer’s requirements shall be followed.

Where requirements for a dedicated blood collection tube are not available, the laboratory shall specify,

verify and validate the usage of an appropriate blood collection tube. This shall include the verification

of the blood collection tube’s compatibility with the intended CTC enrichment, isolation and

examination method.

Blood collection tubes not containing any CTC/RNA stabilizer should only be used, if the specific RNA

molecule or the RNA profile to be examined is stable after blood draw during the entire pre-

examination process or if the requested examination allows the use of such tubes.

Where the laboratory decides to use a blood collection tube without a CTC/RNA stabilizer, the blood

specimen should be processed without delay.

NOTE There are also alternatives to conventional blood collection-based CTC enrichments. These systems

allow for in vivo and ex vivo CTC sampling from larger blood volumes [12] [13].
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5.1.3 Venous whole blood specimen collection from the donor/patient and stabilization

procedures

1. The identity of the person collecting the specimen and the date and time of blood collection

according to EN ISO 15189:2012, 5.4.4.3, f) shall be documented.

2. For the labelling/tagging (sample/specimen identification) of the blood collection tube, a routine

procedure (EN ISO 15189:2012, 5.4.4.3, e) or a procedure with additional information (e.g. 2D-

barcode) shall be used.

3. Standard venipuncture techniques can be used. Steps for preventing possible backflow into the

donor's/patient’s body can be required. The manufacturer's instructions for using the blood

collection tubes shall be followed. A blood collection set and needle holder can be required where

using CTC/RNA stabilizer containing tubes. In this case, the instructions of the collection set and

needle holder manufacturer shall be followed.

NOTE 1 The integrity of CTCs can be influenced by inadequate venous whole blood collection procedures.

4. Blood collection tubes shall be filled in accordance to the manufacturer's instructions and attention

shall be drawn to the correct positioning of the collection tube during the blood draw as well as the

required blood volume.

5. The blood collection tube manufacturer's instructions for mixing or inverting the tube immediately

after blood collection shall be followed. Mixing or inverting the blood collection tube shall be done

gently.

NOTE 2 If the additives in the blood collection tubes are not homogenously mixed with the specimen, the

CTCs can be impacted, which can affect the validity and reliability of the examination results.

6. Any tampering with and/or additions to the specimen shall be documented.

5.1.4 Information on the specimen and storage requirements at the blood collection facility

5.1.4.1 General

As CTCs including their RNA profiles can change significantly after blood collection, thereby affecting

the validity and reliability of the examination result, the documentation regarding the specimen shall

include the date and time of blood collection.

The storage conditions (i.e. storage duration and temperature) shall be documented.

The temporary storage duration in the blood col
...

SLOVENSKI STANDARD
kSIST-TS FprCEN/TS 17390-1:2019
01-september-2019
Molekularne diagnostične preiskave in vitro - Specifikacije za predpreiskovalne

procese za cirkulirajoče tumorske celice (CTC) v venski polni krvi - 1. del: Izolirani

RNK

Molecular in vitro diagnostic examinations - Specifications for pre-examination processes

for circulating tumor cells (CTCs) in venous whole blood - Part 1: Isolated RNA
Molekularanalytische in-vitro-diagnostische Verfahren - Spezifikationen für

präanalytische Prozesse für zirkulierende Tumorzellen (CTC) in venösen Vollblutproben

- Teil 1: Isolierte RNA
Ta slovenski standard je istoveten z: FprCEN/TS 17390-1
ICS:
11.100.10 Diagnostični preskusni In vitro diagnostic test
sistemi in vitro systems
kSIST-TS FprCEN/TS 17390-1:2019 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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kSIST-TS FprCEN/TS 17390-1:2019
FINAL DRAFT
TECHNICAL SPECIFICATION
FprCEN/TS 17390-1
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
July 2019
ICS 11.100.10
English Version
Molecular in vitro diagnostic examinations - Specifications
for pre-examination processes for circulating tumor cells
(CTCs) in venous whole blood - Part 1: Isolated RNA
Molekularanalytische in-vitro-diagnostische Verfahren
- Spezifikationen für präanalytische Prozesse für
zirkulierende Tumorzellen (CTC) in venösen
Vollblutproben - Teil 1: Isolierte RNA

This draft Technical Specification is submitted to CEN members for Vote. It has been drawn up by the Technical Committee

CEN/TC 140.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a Technical Specification. It is distributed for review and comments. It is subject to change

without notice and shall not be referred to as a Technical Specification.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. FprCEN/TS 17390-1:2019 E

worldwide for CEN national Members.
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Contents Page

European foreword ....................................................................................................................................................... 3

Introduction .................................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 5

4 General considerations .............................................................................................................................. 10

5 Outside the laboratory ............................................................................................................................... 11

5.1 Specimen collection ..................................................................................................................................... 11

5.1.1 Information about the specimen donor/patient .............................................................................. 11

5.1.2 Selection of the venous whole blood collection tube by the laboratory .................................. 11

5.1.3 Venous whole blood specimen collection from the donor/patient and stabilization

procedures ...................................................................................................................................................... 12

5.1.4 Information on the specimen and storage requirements at the blood collection

facility ............................................................................................................................................................... 12

5.2 Transport requirements............................................................................................................................ 13

5.2.1 General ............................................................................................................................................................. 13

5.2.2 Using blood collection tubes with stabilizers .................................................................................... 13

5.2.3 Using blood collection tubes without stabilizers.............................................................................. 13

6 Inside the laboratory .................................................................................................................................. 14

6.1 Specimen reception ..................................................................................................................................... 14

6.2 Storage requirements for the venous whole blood specimen ..................................................... 14

6.3 Enrichment of CTCs ..................................................................................................................................... 14

6.3.1 General ............................................................................................................................................................. 14

6.3.2 Using a commercial CTC enrichment system ..................................................................................... 14

6.3.3 Using laboratory’s own CTC enrichment protocols ......................................................................... 15

6.4 Quality of enriched CTCs............................................................................................................................ 15

6.5 Storage of enriched CTCs ........................................................................................................................... 15

6.6 Isolation of CTCs ........................................................................................................................................... 15

6.6.1 General ............................................................................................................................................................. 15

6.6.2 Using a commercial CTC isolation system ........................................................................................... 16

6.6.3 Using the laboratory’s own CTC isolation procedure ..................................................................... 16

6.7 Processing of isolated CTCs ...................................................................................................................... 16

6.8 Isolation of RNA from an enriched CTC sample................................................................................. 17

6.8.1 General ............................................................................................................................................................. 17

6.8.2 Using a commercial RNA isolation kit ................................................................................................... 17

6.8.3 Using the laboratory’s own RNA isolation procedure ..................................................................... 17

6.9 Quantity and quality assessment of isolated RNA from enriched or isolated CTCs ............. 18

6.10 Storage of isolated RNA from enriched CTCs ..................................................................................... 18

6.10.1 General ............................................................................................................................................................. 18

6.10.2 RNA isolated with a commercially available kit ............................................................................... 19

6.10.3 RNA isolated with the laboratory's own protocols .......................................................................... 19

Annex A (informative) Decision guideline for critical steps of the CTC pre-analytical

workflow for RNA isolation ...................................................................................................................... 20

Bibliography ................................................................................................................................................................. 23

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European foreword

This document (FprCEN/TS 17390-1:2019) has been prepared by Technical Committee CEN/TC 140

“In vitro diagnostic medical devices”, the secretariat of which is held by DIN.
This document is currently submitted to the Vote on TS.

CEN/TS 17390 consists of the following parts, under the general title Molecular in vitro diagnostic

examinations — Specifications for pre-examination processes for Circulating Tumor Cells (CTCs) in whole

blood:
— Part 1: Isolated RNA
— Part 2: Isolated DNA
— Part 3: Preparations for analytical CTC staining
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Introduction

Solid tumours release cells and bioanalytes into blood and other body fluids. This has opened the option

of minimally-invasive tumour detection, diagnosis and characterization from venous whole blood

(liquid biopsies). Liquid biopsies are expected to enable earlier detection and diagnosis of cancers and

advance personalized patient treatment. These applications have become one of the fastest growing

segments of the entire diagnostic market.

Circulating tumour cells (CTCs) in venous whole blood reflect the disease complexity that evolves

during tumour progression, with distinct genetic, epigenetic and expression features. Besides the

prognostic role of CTC identification and/or enumeration in cancer progression, CTC molecular

characterization can improve e.g. disease outcome prediction, therapeutic guidance and post-treatment

monitoring of the patient.

CTCs are now considered as a surrogate of tumour tissue in cancer early development, progression and

metastatic phase.

Molecular characterization of CTCs can provide for example a strategy for monitoring cancer genotypes

during systemic therapies [1], identification of mechanisms of disease progression, identification of

novel targets for treatment [2] and to select targeted therapies. Moreover, CTC single-cell sequencing is

emerging as an important tool for tumour genomic heterogeneity analysis [3] [4] [5].

CTCs are fragile and tend to degrade within a few hours when collected in conventional blood collection

tubes, e.g. EDTA containing tubes, without dedicated CTC stabilizers. They are extremely rare,

especially in early disease, e.g. less than 10 cells per 10 ml of blood, representing a ratio of approx. 1:10

CTCs to white blood cells (WBCs). This low ratio represents a significant challenge to CTC enrichment

required for examination.

RNA profiles of CTCs resemble gene expression profiles of tumours. For RNA profile analysis, measures

need to be taken to get rid of the WBCs in order to obtain sufficiently enriched CTC specific RNA.

RNA profiles can change significantly after blood collection, during CTC enrichment and isolation.

Therefore, special measures need to be taken to obtain good quality CTC samples and good quality

isolated RNA for gene expression analysis [4] [6].

Consequently, standardization of all steps of the pre-examination process is required. This includes

blood collection and stabilization, transport, storage, CTC enrichment, CTC isolation (if required), and

RNA isolation. A decision guideline for the critical steps of the CTC pre-analytical workflow for RNA

isolation is provided in Annex A.

This document describes special measures that need to be taken to obtain appropriate quality and

quantity of RNA from CTC containing blood specimens for subsequent examination.
In this document, the following verbal forms are used:
— “shall” indicates a requirement;
— “should” indicates a recommendation;
— “may” indicates a permission;
— “can” indicates a possibility or a capability.
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1 Scope

This document gives guidelines on the handling, storage, processing and documentation of human

venous whole blood specimens intended for the examination of RNA isolated from circulating tumour

cells (CTCs) during the pre-examination phase before a molecular examination is performed.

This document is applicable to molecular in vitro diagnostic examinations including laboratory

developed tests performed by medical laboratories. It is also intended to be used by laboratory

customers, in vitro diagnostics developers and manufacturers, biobanks, institutions and commercial

organizations performing biomedical research, and regulatory authorities.

This document does not cover the isolation of cellular RNA directly from venous whole blood containing

CTCs. This is covered in EN ISO 20186-1, Molecular in vitro diagnostic examinations - Specifications for

pre-examination processes for venous whole blood - Part 1: Isolated cellular RNA.

This document does not cover the isolation of specific white blood cells and subsequent isolation of

cellular RNA therefrom.

This document does not cover pre-analytical workflow requirements for viable CTC cryopreservation

and culturing.

NOTE 1 The requirements given in this document can also be applied to other circulating rare cells (e.g. fetal

cells).

NOTE 2 International, national or regional regulations or requirements can also apply to specific topics

covered in this document.
2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

EN ISO 15189:2012, Medical laboratories - Requirements for quality and competence (ISO 15189:2012,

Corrected version 2014-08-15)
ISO 15190, Medical laboratories — Requirements for safety
3 Terms and definitions

For the purposes of this document, the terms and definitions given in EN ISO 15189 and the following

terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
aliquot

portion of a larger amount of homogenous material, assumed to be taken with negligible sampling error

Note 1 to entry: The term is usually applied to fluids. Tissues are heterogeneous and therefore cannot be

aliquoted.
Note 2 to entry: The definition is derived from References [7], [8] and [9].
[SOURCE: EN ISO 20166-3:2018, 3.1]
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3.2
ambient temperature
unregulated temperature of the surrounding air
[SOURCE: EN ISO 20166-3:2018, 3.2]
3.3
analyte
component represented in the name of a measurable quantity
[SOURCE: EN ISO 17511:2003, 3.2, modified — EXAMPLE has been removed.]
3.4
analytical test performance

accuracy, precision, specificity and sensitivity of a test to measure the analyte of interest

Note 1 to entry: Other test performance characteristics such as robustness, repeatability can apply as well.

[SOURCE: EN ISO 20184-1:2018, 3.4]
3.5
blood collection set

intravenous device specialized for venipuncture consisting of a stainless steel bevelled needle and tube

(tubing) with attached plastic wings and fitting connector

Note 1 to entry: The connector attaches to an additional blood collection device, e.g. a blood collection tube.

3.6
blood collection tube

tube used for blood collection, usually in a vacuum which forces blood from the vein through the needle

and into the tube
3.7
backflow
flow of a liquid opposite to the usual or desired direction
3.8
circulating tumor cells
CTCs

cells present in blood, originating from a primary and/or metastatic site of a tumor

3.9
CTC enrichment
any method that is able to increase the ratio of CTCs to other cells
3.10
CTC isolation
any method resulting in a sample containing CTCs without any other cell types
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3.11
diagnosis

identification of a disease from its signs and symptoms, where the diagnostic process can involve

examinations and tests for classification of an individual's condition into separate and distinct

categories or subclasses that allow medical decisions about treatment and prognosis to be made

[SOURCE: EN ISO 20184-1:2018, 3.6]
3.12
DNase
deoxyribonuclease
enzyme that catalyzes the degradation of DNA into smaller components
[SOURCE: EN ISO 20186-1:2018, 3.11]
3.13
examination
analytical test

set of operations having the object of determining the value or characteristics of a property

Note 1 to entry: Processes that start with the isolated analyte and include all kinds of parameter testing or

chemical manipulation for quantitative or qualitative examination.

[SOURCE: EN ISO 15189:2012, 3.7, modified — Notes to entry 1 to 3 have been removed, Note 1 to

entry has been added and “analytical test” has been added as a preferred term.]
3.14
examination performance
analytical test performance
analytical performance
ability of an examination procedure to measure or detect a particular analyte

Note 1 to entry: Analytical performance is determined from analytical performance studies used to assess the

ability of an in vitro diagnostic examination procedure to measure or detect a particular analyte.

Note 2 to entry: Analytical performance includes such characteristics as analytical sensitivity, detection limit,

analytical specificity (interference and cross-reactivity), trueness, precision and linearity.

[SOURCE: ISO/TS 17822-1:2014, 3.2, modified — “analytical test performance” and “analytical

performance” have been added as preferred terms.]
3.15
examination manufacturer
analytical test manufacturer
group or company that provides the specific analytical test
3.16
needle holder

barrel used in routine venipuncture procedures to hold the blood collection tube in place and to protect

the phlebotomist from direct contact with blood
[SOURCE: EN ISO 20186-1:2018, 3.18]
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3.17
pre-examination processes
preanalytical phase
preanalytical workflow

processes that start, in chronological order, from the clinician’s request and include the examination

request, preparation and identification of the patient, collection of the primary sample(s),

transportation to and within the medical or pathology laboratory, isolation of analytes, and end when

the analytical examination begins

Note 1 to entry: The pre-examination phase includes preparative processes that influence the outcome of the

intended examination.

[SOURCE: EN ISO 15189:2012, 3.15, modified — “pre-analytical workflow” has been added as a

preferred term, Note 1 to entry has been added and the definition has been extended.]

3.18
primary sample
specimen

discrete portion of a body fluid, breath, hair or tissue taken for examination, study or analysis of one or

more quantities or properties assumed to apply for the whole

[SOURCE: EN ISO 15189:2012, 3.16, modified — Notes to entry 1 to 3 have been removed.]

3.19
proficiency testing

evaluation of participant performance against pre-established criteria by means of inter-laboratory

comparisons

[SOURCE: ISO 17043:2010, 3.7, modified — Notes to entry 1 to 3 have been removed.]

3.20
RNA
ribonucleic acid

polymer of ribonucleotides occurring in a double-stranded or single-stranded form

[SOURCE: EN ISO 22174:2005, 3.1.3]
3.21
RNA proficiency testing program
proficiency testing for RNA based examinations
3.22
RNA profile

amounts of different RNA molecules present in a specimen or sample, that can be measured in the

absence of any losses, inhibition and interference
3.23
RNase
ribonuclease
enzyme that catalyzes the degradation of RNA into smaller components
[SOURCE: EN ISO 20186-1:2018, 3.24]
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3.24
room temperature
for the purposes of this document, temperature in the range of 18 °C to 25 °C
Note 1 to entry: Local or national regulations can have different definitions.
3.25
sample
one or more parts taken from a primary sample
[SOURCE: EN ISO 15189:2012, 3.24, modified — EXAMPLE has been removed.]
3.26
stability

ability of a sample material, when stored under specified conditions, to maintain a stated property value

within specified limits for a specified period of time
Note 1 to entry: The analyte for the purpose of this document is RNA.

[SOURCE: ISO Guide 30:2015, 2.1.15, modified — The words “reference material” were replaced by

“sample material”.]
3.27
storage

prolonged interruption of the preanalytical workflow of a sample or analyte respectively, or of their

derivatives e.g., stained sections or tissue blocks, under appropriate conditions in order to preserve

their properties

Note 1 to entry: Long-term storage typically occurs in laboratory archives or in biobanks.

[SOURCE: EN ISO 20166-3:2018, 3.24]
3.28
validation

confirmation, throughout the provision of objective evidence, that the requirements for a specific

intended use or application have been fulfilled

Note 1 to entry: The term “validated” is used to designate the corresponding status.

[SOURCE: EN ISO 9000:2015, 3.8.13, modified — Notes to entry 1 to 3 have been removed.]

3.29
verification

confirmation, through provision of objective evidence, that specified requirements have been fulfilled

Note 1 to entry: The term “verified” is used to designate the corresponding status.

Note 2 to entry: Confirmation can comprise activities such as:
— performing alternative calculations,

— comparing a new design specification with a similar proven design specification,

— undertaking tests and demonstrations, and
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— reviewing documents prior to issue.

[SOURCE: EN ISO 9000:2015, 3.8.12, modified — Notes to entry 1 and 2 have been removed.]

3.30
workflow
series of activities necessary to complete a task
[SOURCE: EN ISO 20166-3:2018, 3.29]
4 General considerations

For general statements on medical laboratory quality management systems and in particular on

specimen collection and handling (including avoidance of cross contaminations), see

EN ISO 15189:2012, 4.2, 5.4.4, or EN ISO/IEC 17020:2012, 7.2 and 8. The requirements on laboratory

equipment, reagents, and consumables according to EN ISO 15189:2012, 5.3 shall be followed;

EN ISO 15189:2012, 5.5.1.2 and 5.5.1.3 and EN ISO/IEC 17020:2012, 6.2 can also apply.

All steps of a diagnostic workflow can influence the final analytical test result. Thus, the entire workflow

including biomolecule stability and specimen and/or sample storage conditions shall be verified and

validated. Workflow steps which cannot always be controlled shall be documented. A risk assessment of

non-controllable workflow steps including their potential impact on the analytical test performance

shall be performed and mitigation measures shall be established to enable the required analytical test

performance.

NOTE CTCs RNA profiles can change significantly after blood collection, e.g. by gene induction, gene down

regulation, RNA degradation [10].

Before or during the design of an examination, it should be investigated and ensured that the specific

RNA profile/s intended to be analysed is/are not compromized in a manner impacting the examination

performance.

CTC analysis usually involves a CTC enrichment step (e.g. by size immunomagnetic-, or microfluidic-

based approaches) prior to RNA isolation. Depending on the requirements of the intended RNA

examination, enriched CTCs can undergo additional steps such as staining and counting for further

characterization. Additionally, the examination can require the isolation of CTCs from the enriched

sample containing an unknown number of CTCs.

Due to the complexity of the pre-analytical workflow, appropriate measures shall be taken to obtain

suitable quantity and quality of enriched CTC RNA.

Safety regulations on specimen transport and handling shall be considered (see EN ISO 15189:2012,

5.2.3 and 5.4.5 and ISO 15190).

During the whole pre-examination process, precautions shall be taken to avoid cross contamination

between different specimens/samples, e.g. by using single-use material whenever feasible or

appropriate cleaning procedures between processing of different specimens/samples.

If a commercial product is not used in accordance with the manufacturer's instructions, responsibility

for its use and performance lies with the user.
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5 Outside the laboratory
5.1 Specimen collection
5.1.1 Information about the specimen donor/patient

The documentation shall include the ID of the specimen donor/patient, which can be in the form of a

code.
The documentation should include, but is not limited to:

a) the relevant health status of the specimen donor/patient (e.g. healthy, disease type, concomitant

disease, demographics (e.g. age and gender));

b) the information about medical treatment and special treatment prior to blood collection;

c) the type and purpose of the proposed examination requested;
d) the appropriate consent from the specimen donor/patient.
See also ISO 15189:2012, 5.4.4.
5.1.2 Selection of the venous whole blood collection tube by the laboratory

Due to the low number of CTCs, a high recovery rate is required during enrichment. This can be

hampered by the potential instability of CTCs during transport and storage, leading to a reduction of the

CTC number in the specimen or reduced compatibility with the enrichment system [11]. Also gene

expression can change within minutes after blood collection.

Therefore, venous whole blood should be collected in appropriate collection tubes with stabilizers

maintaining the integrity of the CTCs and the CTCs RNA profile (CTC/RNA stabilizer).

Where the CTC examination manufacturer requires usage of a dedicated blood collection tube, this shall

be used. Where the CTC examination manufacturer does not specify a dedicated blood collection tube,

but the CTC isolation manufacturer does, this shall be used.

Where requirements on selecting a dedicated blood collection tube are neither available from the CTC

examination manufacturer nor from the CTC isolation manufacturer, the CTC enrichment

manufacturer’s requirements shall be followed.

Where requirements for a dedicated blood collection tube are not available, the laboratory shall specify,

verify and validate the usage of an appropriate blood collection tube. This shall include the verification

of the blood collection tube’s compatibility with the intended CTC enrichment, isolation and

examination method.

Blood collection tubes not containing any CTC/RNA stabilizer should only be used, if the specific RNA

molecule or the RNA profile to be examined is stable after blood draw during the entire pre-

examination process or if the requested examination allows the use of such tubes.

Where the laboratory decides to use a blood collection tube without a CTC/RNA stabilizer, the blood

specimen should be processed without delay.

NOTE There are also alternatives to conventional blood collection-based CTC enrichments. These systems

allow for in vivo and ex vivo CTC sampling from larger blood volumes [12] [13].
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5.1.3 Venous whole blood specimen collection from the donor/patient and stabilization

procedures

1. The identity of the person collecting the specimen and the date and time of blood collection

according to ISO 15189:2012, 5.4.4.3, f) shall be documented.

2. For the labelling/tagging (sample/specimen identification) of the blood collection tube, a routine

procedure (ISO 15189:2012, 5.4.4.3, e) o
...

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