SIST EN ISO 20166-1:2019 PDF

Overview

EN ISO 20166-1:2018 - "Molecular in vitro diagnostic examinations - Specifications for pre‑examination processes for formalin‑fixed and paraffin‑embedded (FFPE) tissue - Part 1: Isolated RNA" provides standardized guidelines for the pre‑examination phase of RNA analysis from FFPE tissue. Published by CEN/ISO, this document defines best practices for handling, documentation, storage and processing of FFPE specimens before molecular assays (e.g., RT‑qPCR and other RNA‑based tests) are performed. It is intended for medical laboratories, molecular pathology labs, IVD developers, biobanks, research organizations and regulatory bodies.

Key topics and technical requirements

The standard covers pre‑analytical processes that directly affect RNA integrity and test reliability. Major technical topics include:

• Specimen collection and documentation: required information about donor/patient and specimen; clear traceability for FFPE samples.
• Transport and reception: transport conditions and reception records to preserve RNA quality during transfer.
• Formalin fixation and paraffin embedding: guidance on fixation handling and embedding workflows that influence RNA modification in FFPE tissue.
• Pathology evaluation and sample selection: criteria for choosing representative tissue regions for downstream RNA extraction.
• Post‑processing steps: post‑fixation of frozen samples, decalcification considerations, and embedding procedures.
• RNA isolation: principles for extracting isolated RNA from FFPE material, including using commercial kits or laboratory‑developed protocols.
• Quantity and quality assessment: assessment steps for RNA yield and integrity prior to molecular testing.
• Storage of FFPE blocks and isolated RNA: recommended storage practices to maintain analyte stability.
• Quality control implications: Annex A discusses RNA QC from FFPE and implications for RT‑qPCR‑based examinations.

The standard uses prescriptive language: "shall" indicates requirements, "should" indicates recommendations.

Practical applications and users

EN ISO 20166-1:2018 is applied to improve reliability and reproducibility of RNA‑based molecular diagnostics and research:

• Clinical molecular pathology labs performing diagnostic RT‑qPCR, sequencing or expression profiling from FFPE tissue.
• Laboratories developing and validating laboratory‑developed tests (LDTs) and IVD manufacturers producing FFPE RNA extraction kits.
• Biobanks and research institutions managing FFPE specimen repositories and ensuring pre‑analytical quality for downstream studies.
• Regulatory authorities and accreditation bodies using standardized pre‑examination criteria for conformity assessment.

Adopting this standard reduces pre‑analytical variability, improves test accuracy and supports compliance with quality and traceability requirements.

Related standards

• ISO 15189:2012 - Medical laboratories - Requirements for quality and competence
• ISO 15190 - Medical laboratories - Requirements for safety
• ISO/IEC 17020:2012 - Conformity assessment - Inspection bodies

Note: national or regional regulations may also apply alongside EN ISO 20166‑1:2018.