6588 Background: Antiestrogen therapy has dramatically improved breast cancer survival rates but weight gain may be problematic. Studies evaluating antiestrogen therapy-related weight gain have yielded mixed results. Our primary objective was to evaluate weight changes in female breast cancer survivors (BCS) who received adjuvant anti-estrogen therapy for stage 0-III breast cancer. Methods: A retrospective chart review was conducted to evaluate weight changes in female chemo naive BCS receiving anti-estrogen therapy. Weights at initiation of hormonal therapy and at 6, 12, 24, and 36 months of follow-up were recorded. Median weight changes were calculated and were compared with Wilcoxon's signed rank test or the Kurskall-Wallis test. Results: A total of 622 women were included. The majority were white (77%), had stage I disease (78%), and were postmenopausal (82%). The median age at diagnosis was 59 years (range, 26–87). Median weight at initiation of hormonal therapy among premenopausal women was 65 kg (range 45.4–122.9). Median weight gain in this group was 0.4 kg (p = 0.009), 0.7 kg (p = 0.013), 1.9 kg (p = 0.0001), and 2.4 kg (p < 0.0001) at 6, 12, 24, and 36 months respectively. Among post-menopausal women, median weight at initiation of therapy was 71.7 kg (range 41.5–152.0) and median weight gain was 0.5 kg (p < 0.0001), 1 kg (p < 0.0001), 0.85 kg (p = 0.001), and 0.85 kg (p = 0.004) at 6, 12, 24, and 36 months respectively. Premenopausal patients had significantly more weight gain at 24 (p = 0.041) and 36 months (p = 0.005), as compared to postmenopausal patients. Among premenopausal women, 110/111 were treated with tamoxifen. Among post-menopausal women (n = 510), hormonal therapy was as follows: unknown n = 28 patients, tamoxifen n = 312, and AI n = 170. Overall, BCS treated with tamoxifen vs an AI had significantly more weight gain at 24 (p = 0.003) and 36 months (p = 0.009). Conclusions: Premenopausal patients are at higher risk for weight gain than postmenopausal patients. Further prospective research is warranted examining weight gain as a long-term side effect of anti-estrogen therapy in BCS. No significant financial relationships to disclose.
Neoadjuvant Hormonal Therapy is Associated with Comparable Outcomes to Neoadjuvant Chemotherapy in Post-Menopausal Women with Estrogen Receptor-Positive Breast Cancer