Randomized trial of a lifestyle intervention for women with early-stage breast cancer (BC) receiving adjuvant hormone therapy: Initial results.

Abstract

512 Background: Obesity is an adverse prognostic factor in early BC. We conducted a randomized clinical trial (RCT) to evaluate a 2-year, centrally delivered, telephone-based weight loss intervention (WLI) compared to a mailed educational intervention (EI) on recurrence, weight loss and QOL in postmenopausal women receiving adjuvant Letrozole. The trial was terminated after 338 of a planned 2,150 women were enrolled due to loss of funding. Methods: 338 women with stage I-IIIa BC were randomized to WLI (n%171) or EI alone (n%167) at 20 centers in Canada and USA. Eligibility included BMI ≥24 kg/m2and <3 years of definitive surgery. WLI involved 19 calls, mailings and a participant manual. Weight loss goal was 10% of baseline via reduction of caloric and fat intake (500-1000 kcal/day, 20% calories fat) and increased physical activity (150-200 minutes/week). Results: Mean age and BMI were 61 years and 31.3 kg/m2. Baseline BMI, adjuvant chemotherapy, and tumor characteristics were balanced between arms. 87.5% of protocol mandated WLI calls took place. Mean weight change is shown in the table. Results were similar for baseline BMI ≥/<30 kg/m2 and adjuvant chemotherapy (yes/no). Mean SF 36 normalized physical component score was improved in WLI vs. EI at 6 (+ 4.1 WLI vs. + 2.1 C, p%0.046) and 12 months (+3.9 WLI vs. + 2.7 EI, p%0.33). Conclusions: A 2-year, telephone-based WLI resulted in significant weight loss at 6, 12, and 18 months in early BC. Results were similar with BMI <30 or 30+ and with or without adjuvant chemotherapy. Follow-up continues to evaluate longer term effects. Funded by Novartis Pharmaceuticals Inc. Sponsored by the Ontario Clinical Oncology Group. Weight (kg) Weight loss intervention Educational intervention P value N Mean (sd) N Mean (sd) Baseline 171 82.7 (15.3) 167 81.3 (14.5) 6 months % Change from baseline 147 -5.6 (4.9) 142 -0.8 (4.9) <.001 12 months % Change from baseline 113 -6.1 (6.2) 121 -0.6 (6.0) <.001 18 months % Change from baseline 68 -5.0 (7.6) 77 -1.2 (6.5) .003