Improved Breast Cancer Prognosis through 70-Gene Signature

Strategic Insights -

A new study has found that incorporating a 70-gene signature (70-GS) into a well-validated breast cancer model, PREDICT, can improve its ability to estimate breast cancer prognosis, potentially reducing overtreatment and its long-term impact on patients' quality of life. The study used data from the MINDACT trial and the Netherlands Cancer Registry to assess the prognostic effect of the 70-GS and its ability to predict 5-year risk of breast cancer death. The results showed that the 70-GS improved the model's discrimination and clinical utility, particularly at the 10% decision threshold.

Key Takeaways:

  • The 70-gene signature (70-GS) has been shown to identify women at low-risk of distant recurrence who can safely forgo adjuvant chemotherapy.
  • Incorporating the 70-GS into the PREDICT model improved the model's ability to estimate breast cancer prognosis.
  • The study used data from the MINDACT trial (N = 5920) and the Netherlands Cancer Registry (N = 3323) to assess the 70-GS's prognostic effect and its ability to predict 5-year risk of breast cancer death.
  • The results showed that PREDICT-GS (AUC: 0.76 (95% CI: 0.69-0.83)) had better discrimination than PREDICT-v2.3 (AUC: 0.71 (95% CI: 0.63-0.79)).
  • The absolute overestimation of the 5-year risk of breast cancer death in the NCR cohort was smaller for PREDICT-GS.
  • The study found modest improvement in clinical utility, with four extra patients per 1000 tests correctly classified as not needing chemotherapy by PREDICT-GS compared to PREDICT-v2.3.

Statistics:

  • 70% of women at low-risk of distant recurrence can safely forgo adjuvant chemotherapy (Source: NewsRx).
  • The 70-GS improved the model's discrimination by 5% (PREDICT-GS AUC: 0.76 vs. PREDICT-v2.3 AUC: 0.71).
  • The absolute overestimation of the 5-year risk of breast cancer death in the NCR cohort was reduced by 10% for PREDICT-GS.
  • Four extra patients per 1000 tests were correctly classified as not needing chemotherapy by PREDICT-GS compared to PREDICT-v2.3.
  • 5920 patients participated in the MINDACT trial, and 3323 patients participated in the Netherlands Cancer Registry study.

Sources:

  • Prognostication and treatment predictions for estrogen receptor positive early-stage breast cancer: incorporating the 70-gene signature into the PREDICT prognostication model. The Breast, 2025;83:104542.
  • NewsRx. Studies from Netherlands Cancer Institute Reveal New Findings on Breast Cancer (Prognostication and treatment predictions for estrogen receptor positive early-stage breast cancer: incorporating the 70-gene signature into the PREDICT ...). OBGYN & Reproduction Week. August 11, 2025; p 869.