# Tumour Banking and Biobanking > Tumour banking for NEET-PG Pathology: consent and ICMR ethics, cold ischaemia time, frozen and FFPE storage, chain of custody and access rules. - Canonical URL: https://prepelephant.com/topics/neet-pg/pathology/tumour-bank-biobanking - Exam / course: NEET-PG · Subject: Pathology - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-02 - Last updated: 2026-10-02 - How to cite: "Tumour Banking and Biobanking", PrepElephant, https://prepelephant.com/topics/neet-pg/pathology/tumour-bank-biobanking ## Direct answer A tumour bank is a curated repository of human tissue and linked clinical data collected under consent, standard operating procedures and chain-of-custody documentation, existing to power future research rather than today's diagnosis. Fresh tumour is triaged at the bench — one portion snap-frozen in liquid nitrogen or its vapour phase, one embedded in OCT for frozen sections, one fixed in formalin as a matched paraffin block — after a pathologist confirms tumour content on a rapid section. Two numbers govern quality: cold ischaemia time, ideally under an hour from vessel ligation to freezing because RNA degrades steadily, and tumour cellularity, commonly aimed above seventy percent with minimal necrosis. In India, consent and custodianship follow ICMR national ethical guidance, with institution-held custody and material transfer agreements governing sharing. ## What you must remember - **Consent first:** broad or tiered consent for unspecified future research, with documented right to withdraw; Indian practice follows the ICMR National Ethical Guidelines for biomedical research, which carry specific biobanking provisions (per current ICMR guidance). - **Cold ischaemia clock:** target under one hour from removal to stabilisation; RNA integrity numbers fall measurably with delay, and -20 degrees storage adds ice-crystal damage. - **Mirror-image triage:** snap-frozen tissue in liquid nitrogen or vapour phase (below about -150 degrees Celsius), OCT-embedded tissue, RNAlater for small samples, and a matched formalin-fixed paraffin block for histological correlation. - **Pathologist verification:** a rapid section confirms viable tumour, estimates cellularity and necrosis — banking never compromises the diagnostic specimen; surplus tissue only. - **Storage engineering:** alarmed mechanical freezers at -80 degrees as working stock, liquid nitrogen vapour phase for long-term, dewars monitored and logged; paraffin blocks in a cool, dry archive. - **Data and custody:** coded identifiers linked to clinical annotation in a laboratory information system; custodianship rests with the institution, not the surgeon or investigator; external release needs a material transfer agreement and ethics approval. - **Quality audits:** periodic RNA integrity checking, STR profiling to detect swaps or contamination, temperature logs and a full chain-of-custody audit trail; ISBER best practices are the usual international reference. ## One afternoon in an Indian cancer centre bank A radical gastrectomy arrives in the bank's theatre liaison box twenty-five minutes after ligation. The pathology resident opens it fresh, photographs and weighs it, takes the diagnostic blocks first, then samples tumour and matched normal gastric mucosa from a margin far from the lesion. Slabs go into cryomoulds with OCT, others into cryovials dropped into liquid nitrogen; one fragment travels in RNAlater for a collaborating genomics laboratory. A frozen section from the aliquot shows ninety percent viable tumour, so the deposit is accepted and logged. Months later a researcher requests aliquots: the request goes to the institutional ethics committee, a material transfer agreement is executed, and coded vials with stripped identifiers leave with an annotation sheet. Every step — the timing, the cellularity estimate, the approvals — exists in the record, because a biospecimen without provenance is scientifically worthless no matter how cold it was kept. ## How the exam frames biobanking Viva questions cluster on the two clocks and the ethics. Why snap-freeze rather than use a domestic -20 degree freezer? Because slow freezing forms ice crystals that rupture cells and because RNases stay active; liquid nitrogen or vapour phase stops both. What is an acceptable RNA integrity number? Above about seven is generally regarded as good quality for most assays, though thresholds vary by platform — quote it as a hedge, not a commandment. The ethical angles examiners probe: who owns banked tissue (the institution as custodian, under consent), what a variant of uncertain significance means for returning results, and why coded rather than anonymised storage — coded samples allow re-contact and clinical follow-up linkage, which anonymised samples destroy. Candidates who can link cold ischaemia, STR audit and consent type into one sentence usually walk away with the marks. ## Frequently asked questions ### What is cold ischaemia time in tumour banking? The interval from vascular ligation (or removal) to stabilisation of tissue; under one hour is the usual quality target because RNA degrades progressively. ### Which Indian framework governs biobank ethics? The ICMR National Ethical Guidelines for biomedical and health research, with biobanking-specific provisions, interpreted by the institutional ethics committee. ### Why is tissue stored in liquid nitrogen vapour phase rather than at -20 degrees? Vapour phase (below about -150 degrees Celsius) halts enzymatic degradation and ice-crystal damage that occur at ordinary freezer temperatures. ### What is an RNA integrity number and what value is acceptable? A score of tissue RNA quality from electrophoretic profiling; values around seven or higher are broadly acceptable, though platform-dependent. ### How is a sample swap or contamination detected in a bank? Short tandem repeat profiling compares aliquot DNA with the donor's reference genotype, exposing mismatches.