Medline ® Abstract for Reference 103
of 'Prognostic and predictive factors in early, nonmetastatic breast cancer'
Association between the 21-gene recurrence score assay and risk of locoregional recurrence in node-negative, estrogen receptor-positive breast cancer: results from NSABP B-14 and NSABP B-20.
Mamounas EP, Tang G, Fisher B, Paik S, Shak S, Costantino JP, Watson D, Geyer CE Jr, Wickerham DL, Wolmark N
J Clin Oncol. 2010;28(10):1677. Epub 2010 Jan 11.
PURPOSE: The 21-gene OncotypeDX recurrence score (RS) assay quantifies the risk of distant recurrence in tamoxifen-treated patients with node-negative, estrogen receptor (ER)-positive breast cancer. We investigated the association between RS and risk for locoregional recurrence (LRR) in patients with node-negative, ER-positive breast cancer from two National Surgical Adjuvant Breast and Bowel Project (NSABP) trials (NSABP B-14 and B-20).
PATIENTS AND METHODS: RS was available for 895 tamoxifen-treated patients (from both trials), 355 placebo-treated patients (from B-14), and 424 chemotherapy plus tamoxifen-treated patients (from B-20). The primary end point was time to first LRR. Distant metastases, second primary cancers, and deaths before LRR were censored.
RESULTS: In tamoxifen-treated patients, LRR was significantly associated with RS risk groups (P<.001). The 10-year Kaplan-Meier estimate of LRR was 4.% (95% CI, 2.3% to 6.3%) for patients with a low RS (<18), 7.2% (95% CI, 3.4% to 11.0%) for those with intermediate RS (18-30), and 15.8% (95% CI, 10.4% to 21.2%) for those with a high RS (>30). There were also significant associations between RS and LRR in placebo-treated patients from B-14 (P = .022) and in chemotherapy plus tamoxifen-treated patients from B-20 (P = .028). In multivariate analysis, RS was an independent significant predictor of LRR along with age and type of initial treatment.
CONCLUSION: Similar to the association between RS and risk for distant recurrence, a significant association exists between RS and risk for LRR. This information has biologic consequences and potential clinical implications relative to locoregional therapy decisions for patients with node-negative and ER-positive breast cancer.
National Surgical Adjuvant Breast and Bowel Project Operations and Biostatistical Centers, Departmentof Biostatistics, Graduate School of Public Health, University of Pittsburgh, USA. firstname.lastname@example.org