Predictors of early relapse in postmenopausal women with hormone receptor-positive breast cancer in the BIG 1-98 trial

Publication

Predictors of early relapse in postmenopausal women with hormone receptor-positive breast cancer in the BIG 1-98 trial

Journal Paper/Review - May 1, 2007

Mauriac L, Castiglione-Gertsch M, Price K N, Coates A S, Smith I, Viale G, Rabaglio M, Zabaznyi N, Goldhirsch A, BIG 1-98 Collaborative Group, Gelber R D, Nogaret J-M, Keshaviah A, Debled M, Mouridsen H, Forbes J F, Thürlimann Beat, Paridaens R, Monnier A, Láng I, Wardley A, International Breast Cancer Study Group

Citation

Mauriac L, Castiglione-Gertsch M, Price K, Coates A, Smith I, Viale G, Rabaglio M, Zabaznyi N, Goldhirsch A, BIG 1-98 Collaborative Group, Gelber R, Nogaret J, Keshaviah A, Debled M, Mouridsen H, Forbes J, Thürlimann B, Paridaens R, Monnier A, Láng I, Wardley A, International Breast Cancer Study Group. Predictors of early relapse in postmenopausal women with hormone receptor-positive breast cancer in the BIG 1-98 trial. Ann Oncol 2007; 18:859-67.

Type

Journal Paper/Review (English)

Journal

Ann Oncol 2007; 18

Publication Date

May 1, 2007

Issn Print

0923-7534

Pages

859-67

Brief description/objective

BACKGROUND: Aromatase inhibitors are considered standard adjuvant endocrine treatment of postmenopausal women with hormone receptor-positive breast cancer, but it remains uncertain whether aromatase inhibitors should be given upfront or sequentially with tamoxifen. Awaiting results from ongoing randomized trials, we examined prognostic factors of an early relapse among patients in the BIG 1-98 trial to aid in treatment choices. PATIENTS AND METHODS: Analyses included all 7707 eligible patients treated on BIG 1-98. The median follow-up was 2 years, and the primary end point was breast cancer relapse. Cox proportional hazards regression was used to identify prognostic factors. RESULTS: Two hundred and eighty-five patients (3.7%) had an early relapse (3.1% on letrozole, 4.4% on tamoxifen). Predictive factors for early relapse were node positivity (P < 0.001), absence of both receptors being positive (P < 0.001), high tumor grade (P < 0.001), HER-2 overexpression/amplification (P < 0.001), large tumor size (P = 0.001), treatment with tamoxifen (P = 0.002), and vascular invasion (P = 0.02). There were no significant interactions between treatment and the covariates, though letrozole appeared to provide a greater than average reduction in the risk of early relapse in patients with many involved lymph nodes, large tumors, and vascular invasion present. CONCLUSION: Upfront letrozole resulted in significantly fewer early relapses than tamoxifen, even after adjusting for significant prognostic factors.