# Comparison of breast cancer molecular features and survival by African and European ancestry in The Cancer Genome Atlas

Source: https://onco.cc/key-papers/paper-huo-tcga-ancestry-breast-jama-oncol-2017/  
OnCo record `paper-huo-tcga-ancestry-breast-jama-oncol-2017` (Key paper). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Among 930 TCGA patients, those of African ancestry were nearly four times as likely to have basal-like cancer, had more TP53 and fewer PIK3CA mutations and relapsed sooner; about 44% of the subtype difference was explained by inherited variants.

## Summary

Tumour and matched normal data for 930 TCGA breast cancer patients (154 black patients of African ancestry, 776 white of European ancestry) were compared. Black patients had a worse breast cancer-free interval (HR 1.67), higher odds of basal-like (OR 3.80) and HER2-enriched (OR 2.22) subtypes, more TP53 and fewer PIK3CA mutations. Most molecular differences disappeared after adjusting for intrinsic subtype, leaving 16 methylation probes, 4 copy-number segments, 1 protein and 142 genes differentially expressed. Heritability of basal versus non-basal subtype from germline genotypes was 0.436; the ER-negative polygenic risk score was much higher in black patients.

## Fields

- Kind: Key paper
- Last checked: 2026-09-24
- Journal: JAMA Oncology
- Year: 2017
- DOI: 10.1001/jamaoncol.2017.0595
- Authors: Huo D, Hu H, Rhie SK, et al.
- Findings: African ancestry: basal-like OR 3.80, HER2-enriched OR 2.22, breast cancer-free interval HR 1.67.; More TP53 and fewer PIK3CA mutations; most differences explained by subtype.; Heritability of basal versus non-basal subtype 0.436; higher ER-negative polygenic risk score.
- What it means: The excess of triple-negative disease in women of African ancestry is substantially genetic in origin rather than only social, which supports ancestry-aware risk models and trial enrolment.
- Caveats: Convenience cohort with self-reported race refined by genotype; 154 black patients.; Survival follow-up in TCGA is short.

## Sources

- Huo et al., JAMA Oncol 2017: breast cancer molecular features by African and European ancestry in TCGA: https://doi.org/10.1001/jamaoncol.2017.0595
- PubMed: https://pubmed.ncbi.nlm.nih.gov/28472234/

## Connected records

- cancers: [Breast cancer (all types)](https://onco.cc/cancers/breast-cancer/), [Triple-negative breast cancer (TNBC)](https://onco.cc/cancers/tnbc/)
- targets: [PIK3CA / PI3K-alpha](https://onco.cc/targets/pik3ca/), [TP53](https://onco.cc/targets/tp53/)
- terms: [PAM50 / intrinsic subtypes](https://onco.cc/terms/pam50/)
- journals: [JAMA Oncology](https://onco.cc/journals/jama-oncology/)

---
JSON: https://onco.cc/api/v1/entities/paper-huo-tcga-ancestry-breast-jama-oncol-2017.json