ISO 20184-1:2018

Overview - ISO 20184-1:2018 (Frozen tissue - Isolated RNA)

ISO 20184-1:2018 provides standardized pre-examination guidance for handling, documenting, storing and processing frozen tissue specimens intended for RNA analysis in molecular in vitro diagnostic (IVD) workflows. The document addresses the entire pre-analytical phase - from specimen collection and transport to RNA isolation and storage of isolated RNA - and is applicable to medical laboratories, molecular pathology labs, biobanks, IVD developers, researchers and regulatory authorities. Note: tissues chemically stabilized before freezing are excluded.

Key technical topics and requirements

The standard structures the pre-examination process and defines requirements and recommendations using the conventional ISO verbs (“shall” = requirement, “should” = recommendation):

• Specimen collection and documentation
  • Required information about the specimen donor/patient and about the specimen itself (collection metadata).
• Transport of fresh tissue
  • Preparations and conditions for safe transport to the laboratory to minimise pre-analytical changes.
• Reception and sample selection
  • Recording reception details and pathology evaluation to select representative frozen sample(s).
• Freezing and storage of tissue
  • Procedures for freezing samples and storing frozen tissue to preserve RNA integrity (includes storage considerations and definitions such as room temperature = 18–25 °C).
• Isolation of RNA
  • General requirements, recommendations, and options for using commercial kits or in‑house protocols; RNase control and prevention of degradation are emphasised.
• Quantity and quality assessment
  • Guidance on assessing the amount and integrity of isolated RNA before analytical assays.
• Storage of isolated RNA
  • Conditions and documentation for archiving extracted RNA for short- and long-term use.
• Definitions and pre-analytical vocabulary
  • Key terms such as cold ischemia, warm ischemia, RNA profile, RNase and aliquot are defined for clarity.
• Informative annex
  • Annex A discusses the impact of pre-examination variables (example: effects on RNA profiles from frozen liver tissue), illustrating practical effects of handling decisions.

Practical applications - who uses ISO 20184-1

• Clinical and molecular pathology laboratories implementing reliable RNA-based diagnostics.
• Biobanks and sample repositories standardizing frozen tissue handling for downstream RNA assays.
• IVD manufacturers and kit developers designing validated RNA extraction workflows and instructions for use.
• Biomedical researchers needing reproducible pre-analytical processes for transcriptomic studies.
• Regulatory bodies and quality managers ensuring compliance with robust pre-examination practices.

Related standards and cross-reference

• ISO 15189:2012 - Medical laboratories - Requirements for quality and competence (referenced normative document).
• ISO 20184 series - other parts of the series are listed on the ISO website for complementary pre-examination guidance.

Keywords: ISO 20184-1:2018, pre-examination, frozen tissue, isolated RNA, RNA extraction, molecular in vitro diagnostic, pre-analytical workflow, molecular pathology, biobank, RNA quality.