Obesity and risk of recurrence or death after adjuvant endocrine therapy with letrozole or tamoxifen in the breast international group 1-98 trial

Publication

Obesity and risk of recurrence or death after adjuvant endocrine therapy with letrozole or tamoxifen in the breast international group 1-98 trial

Journal Paper/Review - Oct 8, 2012

Ewertz Marianne, Goldhirsch Aron, Coates Alan S, Smith Ian E, Láng István, Colleoni Marco, Gelber Richard D, Rabaglio Manuela, Paridaens Robert J, Forbes John F, Bonnefoi Hervé, Thürlimann Beat, Price Karen N, Ejlertsen Bent, Regan Meredith M, Gray Kathryn P, Mouridsen Henning T

Citation

Ewertz M, Goldhirsch A, Coates A, Smith I, Láng I, Colleoni M, Gelber R, Rabaglio M, Paridaens R, Forbes J, Bonnefoi H, Thürlimann B, Price K, Ejlertsen B, Regan M, Gray K, Mouridsen H. Obesity and risk of recurrence or death after adjuvant endocrine therapy with letrozole or tamoxifen in the breast international group 1-98 trial. J Clin Oncol 2012; 30:3967-75.

Type

Journal Paper/Review (English)

Journal

J Clin Oncol 2012; 30

Publication Date

Oct 8, 2012

Issn Electronic

1527-7755

Pages

3967-75

Brief description/objective

PURPOSE To examine the association of baseline body mass index (BMI) with the risk of recurrence or death in postmenopausal women with early-stage breast cancer receiving adjuvant tamoxifen or letrozole in the Breast International Group (BIG) 1-98 trial at 8.7 years of median follow-up. PATIENTS AND METHODS This report analyzes 4,760 patients with breast cancer randomly assigned to 5 years of monotherapy with letrozole or tamoxifen in the BIG 1-98 trial with available information on BMI at randomization. Multivariable Cox modeling assessed the association of BMI with disease-free survival, overall survival (OS), breast cancer-free interval, and distant recurrence-free interval and tested for treatment-by-BMI interaction. Median follow-up was 8.7 years. Results Seventeen percent of patients have died. Obese patients (BMI ≥ 30 kg/m(2)) had slightly poorer OS (hazard ratio [HR] = 1.19; 95% CI, 0.99 to 1.44) than patients with normal BMI (< 25 kg/m(2)), whereas no trend in OS was observed in overweight (BMI 25 to < 30 kg/m(2)) versus normal-weight patients (HR = 1.02; 95% CI, 0.86 to 1.20). Treatment-by-BMI interactions were not statistically significant. The HRs for OS comparing obese versus normal BMI were HR = 1.22 (95% CI, 0.93 to 1.60) and HR = 1.18 (95% CI, 0.91 to 1.52) in the letrozole and tamoxifen groups, respectively. CONCLUSION There was no evidence that the benefit of letrozole over tamoxifen differed according to patients' BMI.