Journal Article

Breast-cancer-specific mortality in patients treated based on the 21-gene assay: a SEER population-based study

Baehner, Frederick L, Hernandez, Brenda Y, Mueller, Lloyd, Stroup, Antoinette, Wiggins, Charles, Schwartz, Ann G, Cronin, Kathleen, Howe, Will, Ward, Kevin C, Schwartz, Stephen M, Shak, Steven, Schussler, Nicola, Howlader, Nadia, Penberthy, Lynne, Sweeney, Carol, Cress, Rosemary, Petkov, Valentina I, Deapen, Dennis, Glaser, Sally L, Tucker, Thomas C, Wu, Xiao-Cheng, Lynch, Charles F, Miller, Dave P, Gliner, Nathan

2016

Overview

The 21-gene Recurrence Score assay is validated to predict recurrence risk and chemotherapy benefit in hormone-receptor-positive (HR+) invasive breast cancer. To determine prospective breast-cancer-specific mortality (BCSM) outcomes by baseline Recurrence Score results and clinical covariates, the National Cancer Institute collaborated with Genomic Health and 14 population-based registries in the the Surveillance, Epidemiology, and End Results (SEER) Program to electronically supplement cancer surveillance data with Recurrence Score results. The prespecified primary analysis cohort was 40–84 years of age, and had node-negative, HR+, HER2-negative, nonmetastatic disease diagnosed between January 2004 and December 2011 in the entire SEER population, and Recurrence Score results ( N =38,568). Unadjusted 5-year BCSM were 0.4% ( n =21,023; 95% confidence interval (CI), 0.3–0.6%), 1.4% ( n =14,494; 95% CI, 1.1–1.7%), and 4.4% ( n =3,051; 95% CI, 3.4–5.6%) for Recurrence Score <18, 18–30, and ⩾31 groups, respectively ( P <0.001). In multivariable analysis adjusted for age, tumor size, grade, and race, the Recurrence Score result predicted BCSM ( P <0.001). Among patients with node-positive disease (micrometastases and up to three positive nodes; N =4,691), 5-year BCSM (unadjusted) was 1.0% ( n =2,694; 95% CI, 0.5–2.0%), 2.3% ( n =1,669; 95% CI, 1.3–4.1%), and 14.3% ( n =328; 95% CI, 8.4–23.8%) for Recurrence Score <18, 18–30, ⩾31 groups, respectively ( P <0.001). Five-year BCSM by Recurrence Score group are reported for important patient subgroups, including age, race, tumor size, grade, and socioeconomic status. This SEER study represents the largest report of prospective BCSM outcomes based on Recurrence Score results for patients with HR+, HER2-negative, node-negative, or node-positive breast cancer, including subgroups often under-represented in clinical trials. Diagnostics: Gene test predicts death from breast cancer A common gene-panel test can help to predict the likelihood of women with breast cancer dying from the disease. Valentina Petkov at the US National Cancer Institute in Maryland and her colleagues studied a form of breast cancer that responds to hormone therapy in more than 44,500 American patients with and without spread to the lymph nodes. At diagnosis, all had taken a genomic test called Oncotype DX, which estimates the likelihood of breast-cancer recurrence on the basis of expression data from 21 genes. The team found that the test’s ‘recurrence score’ was strongly associated with the chance of death from breast cancer — independent of patient age, tumor size and tumor grade. The study provides the best evidence to date that Oncotype DX can be used to predict mortality risk, including for racial minority and other under-represented groups.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 631/67/1347 / 692/4028/67/1347 / Biomedicine / Cancer Research / Cell Biology / Human Genetics / Oncology