# c-TRAK TN analysis: tissue-free versus tumour-informed ctDNA assays for residual disease in early triple-negative breast cancer

Source: https://onco.cc/key-papers/paper-ctrak-tn-tissue-free-mrd-jamaoncol-2026/  
OnCo record `paper-ctrak-tn-tissue-free-mrd-jamaoncol-2026` (Key paper). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

A blood test that needs no tumour sample found leftover cancer DNA in a third of women after treatment for triple-negative breast cancer, and those women were far more likely to relapse; it agreed closely with the tests that first sequence the tumour.

## Summary

Prognostic and exploratory analysis of the ctDNA surveillance period of c-TRAK TN, a multicentre phase 2 study in triple-negative breast cancer at moderate to high risk of recurrence. Plasma was collected every three months for up to two years after adjuvant therapy. A tissue-free methylation assay was compared with digital PCR and whole-exome-powered tumour-informed assays across 1,026 samples from 159 patients.

## Fields

- Kind: Key paper
- Last checked: 2026-09-21
- Journal: JAMA Oncology
- Year: 2026
- DOI: 10.1001/jamaoncol.2026.2833
- Authors: Cunningham N, Cutts RJ, Swift C, et al.
- Findings: The tissue-free assay detected ctDNA in 54 of 159 patients (34 percent).; Detection was strongly associated with recurrence: hazard ratio 27.2 (95 percent CI 13.7 to 54.2) for recurrence-free survival.
- What it means: Residual-disease testing may not need the tumour to be sequenced first, which would remove the slowest step of tumour-informed assays; the comparison with tumour-informed results in the same patients is the evidence that matters.
- Caveats: Exploratory analysis of a phase 2 study, not a randomised comparison of assays.; Single cancer type and a moderate to high-risk population; performance in other settings is untested.; Follow-up through January 2023 with analysis in 2025 to 2026.

## Sources

- JAMA Oncology 2026: https://doi.org/10.1001/jamaoncol.2026.2833
- PubMed: https://pubmed.ncbi.nlm.nih.gov/42593771/

## Connected records

- cancers: [Triple-negative breast cancer (TNBC)](https://onco.cc/cancers/tnbc/)
- technologies: [Liquid biopsy (ctDNA)](https://onco.cc/technologies/liquid-biopsy/), [MRD / molecular residual disease testing](https://onco.cc/technologies/mrd-testing/)
- terms: [Circulating tumour DNA (ctDNA)](https://onco.cc/terms/ctdna/), [Minimal / molecular residual disease (MRD)](https://onco.cc/terms/mrd/), [Tumour-informed versus tumour-naive ctDNA assays](https://onco.cc/terms/tumour-informed-assay/)
- journals: [JAMA Oncology](https://onco.cc/journals/jama-oncology/)

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