DISP-39. Clinical Characteristics and Survival Outcomes Among Male Breast Cancer Patients with Brain Metastases: A Retrospective Analysis

Abstract BACKGROUND Male breast cancer is uncommon, accounting for approximately 1% of cancers that occur in men and 1% of all breast cancers worldwide. Due to its rarity, the clinical course and treatment of male breast cancer remain poorly defined, with most management strategies derived from studies conducted in female patients. Brain metastases (BM) in male breast cancer patients are exceedingly rare and have not been well characterized. This study aims to describe the clinical characteristics and survival outcomes of male breast cancer patients with BM using the National Cancer Database. METHODS We identified 123 male breast cancer patients with BM from a population of 35,613 cases. Demographics, race, Hispanic origin, insurance status, and treatment details were summarized. Kaplan–Meier methods were used to estimate overall survival (OS), with survival probabilities reported at defined time points. RESULTS Among the 123 (0.3%) patients with BM, 51.2% were <65 years old, 75.6% were White, and 94.3% were non-Hispanic. Most were insured through government programs (59.4%). Systemic therapy, including chemotherapy and hormone therapy, was administered in 50.8% of patients, while 44.7% received radiation therapy. Among 109 patients with complete survival data, the median OS was 7.8 months (95% CI: 5.0–12.2). Kaplan–Meier estimates showed a 12-month survival of 41.4% (95% CI: 31.9–50.6), 24-month survival of 26.3% (95% CI: 18.2–35.1), 36-month survival of 15.1% (95% CI: 8.6–23.3), and 60-month survival of 5.4% (95% CI: 1.6–12.7). CONCLUSIONS Survival outcomes in male breast cancer patients with brain metastases remain dismal, with less than half surviving beyond one year. Given the rarity and poor prognosis, further research is warranted to understand disease biology, identify prognostic markers, and optimize multidisciplinary treatment approaches to improve outcomes in this unique patient population.