# Mandatory interval-cancer audit for every blood-based screening test

Source: https://onco.cc/ideas/idea-prev-interval-cancer-audit-blood-tests/  
OnCo record `idea-prev-interval-cancer-audit-blood-tests` (Idea). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

When a screening test misses a cancer, we should know. Linking every negative result to the cancer registry and publishing what was missed, by stage, should be a condition of use.

## Summary

Cervical and breast programmes audit interval cancers routinely; commercial blood tests do not. Propose that authorisation or reimbursement for MCED and single-cancer blood tests requires registry linkage of all negatives, with annual publication of stage-specific sensitivity, interval cancer rates, and test-negative cancers by subtype.

## Fields

- Kind: Idea
- Last checked: 2026-09-08
- Hypothesis: Registry-linked audit will reveal real-world stage I sensitivity materially below case-control estimates for at least some cancers, and will change which tests payers cover.
- Rationale: Case-control designs overstate sensitivity through spectrum bias; only prospective negatives tell the truth. The audit is cheap where registries exist.
- Proposed test: Pilot with one approved test (e.g. Shield for colorectal cancer) in a state with a complete registry; publish the two-year interval cancer rate.
- Maturity: speculative
- Actor: regulator

## Sources

- Bottleneck evidence (The hardest cancers are found late): Crosby et al., Early detection of cancer (Science 2022): https://doi.org/10.1126/science.aay9040

## Connected records

- collections: [SEER (Surveillance, Epidemiology, and End Results)](https://onco.cc/collections/seer/)
- fronts: [Early Detection & Screening](https://onco.cc/fronts/early-detection/)
- technologies: [Liquid biopsy (ctDNA)](https://onco.cc/technologies/liquid-biopsy/), [Multi-cancer early detection (MCED)](https://onco.cc/technologies/mced/)
- drugs: [Galleri](https://onco.cc/drugs/galleri/), [Shield](https://onco.cc/drugs/shield/)
- terms: [Real-world evidence](https://onco.cc/terms/real-world-evidence/)
- bottlenecks: [Biomarkers are not validated or standardised](https://onco.cc/bottlenecks/b-biomarker-validation/), [The hardest cancers are found late](https://onco.cc/bottlenecks/b-early-detection/), [Weak real-world evidence and registries](https://onco.cc/bottlenecks/b-real-world-evidence/)
- key papers: [Early detection of cancer](https://onco.cc/key-papers/paper-crosby-science/)

---
JSON: https://onco.cc/api/v1/entities/idea-prev-interval-cancer-audit-blood-tests.json