# Strip the platelet coat off travelling tumour cells in ctDNA-positive patients

Source: https://onco.cc/ideas/idea-bio2-platelet-cloak-aspirin-mrd/  
OnCo record `idea-bio2-platelet-cloak-aspirin-mrd` (Idea). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Cancer cells in the blood wrap themselves in platelets as camouflage. Aspirin may remove that cloak, and it is cheapest to test in the patients at highest risk of relapse.

## Summary

Platelet cloaking shields circulating tumour cells from natural killer cells and shear stress and supplies TGF-beta that drives epithelial-mesenchymal transition. Aspirin has adjuvant signals in PIK3CA-pathway-mutant colorectal cancer and is being tested at scale in unselected populations, but no trial has enriched for molecular residual disease, where the event rate is high and the biology is precisely platelet-tumour cell interaction.

## Fields

- Kind: Idea
- Last checked: 2026-09-08
- Hypothesis: In patients who are ctDNA-positive after curative surgery, aspirin added to standard care produces higher ctDNA clearance at six months than standard care alone.
- Rationale: An MRD-enriched design turns a small absolute effect in an unselected population into a testable large relative effect in a small trial, and gives a molecular endpoint that reads out in months rather than years.
- Proposed test: A 200-patient randomised trial inside an existing MRD platform in colorectal or breast cancer, with six-month ctDNA clearance as primary endpoint and platelet-CTC imaging as a mechanistic substudy.
- Maturity: early-clinical
- Actor: research

## Sources

- Bottleneck evidence (Metastasis is understood least and studied last): Dillekås et al., Are 90% of deaths from cancer caused by metastases? (Cancer Medicine 2019): https://doi.org/10.1002/cam4.2474

## Connected records

- cancers: [Colorectal cancer](https://onco.cc/cancers/colorectal/), [HR-positive / HER2-negative breast cancer](https://onco.cc/cancers/breast-hr-positive/)
- technologies: [Aspirin for cancer prevention and adjuvant therapy](https://onco.cc/technologies/aspirin-cancer-prevention/), [Liquid biopsy (ctDNA)](https://onco.cc/technologies/liquid-biopsy/), [MRD / molecular residual disease testing](https://onco.cc/technologies/mrd-testing/)
- pathways: [Epithelial-mesenchymal transition & drug efflux](https://onco.cc/pathways/emt/)
- trials: [CIRCULATE-Japan (GALAXY / VEGA / ALTAIR)](https://onco.cc/trials/circulate-japan/), [DYNAMIC](https://onco.cc/trials/dynamic/)
- bottlenecks: [Dormant cells and minimal residual disease](https://onco.cc/bottlenecks/b-dormancy-mrd/), [Metastasis is understood least and studied last](https://onco.cc/bottlenecks/b-metastasis-biology/), [No incentive to repurpose cheap drugs](https://onco.cc/bottlenecks/b-generic-repurposing/)
- key papers: [Are 90% of deaths from cancer caused by metastases?](https://onco.cc/key-papers/paper-dillekas-cancer-med/)

---
JSON: https://onco.cc/api/v1/entities/idea-bio2-platelet-cloak-aspirin-mrd.json