Overview
ISO/TS 4425:2023 - Genomics informatics specifies standardized data elements and metadata for describing microsatellite instability (MSI) information generated by clinical massive parallel DNA sequencing (NGS). The Technical Specification defines what to report about MSI as a biomarker - including MSI status, supporting metadata on resources, data generation conditions, and data processing - to improve clinical interpretation, interoperability, and secondary research use. It does not define laboratory methods or MSI calculation algorithms, apply to non‑human species, or cover Sanger sequencing.
Key topics and requirements
ISO/TS 4425 organizes MSI reporting into structured elements and metadata to ensure clarity and traceability. Key technical topics include:
- Composition of report: summary and detailed parts for MSI status presentation.
- Required fields: clinical sequencing order identifiers, date/time (ISO 8601), performing laboratory details, legally authorized requester, and subject‑of‑care identifiers.
- Patient and specimen metadata: subject of care demographics (birth date, sex, ancestry), referring diagnosis, and biospecimen type.
- MSI result information: declared MSI status, supporting values and descriptors necessary for clinical decisions.
- Analytical provenance: resources used (reference genome), data generation conditions, sequencing platform, analysis platform and parameters.
- Quality and optional metadata: sequencing quality control metrics, genomic positions used to determine MSI, criteria applied for MSI classification, and clinical implications.
- Treatment and follow‑up: optional fields for recommended treatments, medication, clinical trial links, and supporting evidence.
The specification prioritizes standardized nomenclature, metadata completeness, and machine‑readable reporting to support integration into electronic health records and clinical pipelines.
Applications and users
ISO/TS 4425 is practical for:
- Clinical sequencing laboratories reporting MSI results from NGS.
- Bioinformatics and software developers building variant/M SI reporting tools and pipelines.
- Electronic health record (EHR) integrators and LIS vendors ensuring interoperable MSI data exchange.
- Diagnostic manufacturers and regulatory bodies aligning MSI outputs for companion diagnostics.
- Clinicians and researchers who require consistent MSI metadata for treatment selection, immunotherapy decisions, and cross‑study comparisons.
Use cases include standardized MSI reports for oncology clinical decision‑making, multi‑center research meta‑analysis, and regulatory submissions for NGS‑based assays.
Related standards
Keywords: ISO/TS 4425:2023, microsatellite instability, MSI, genomics informatics, clinical NGS, metadata, biomarker reporting, electronic health records, sequencing platform, bioinformatics.