Factors Associated with Recurrence Rates and Long-Term Survival in Women Diagnosed with Breast Cancer Ages 40 and Younger.

Background: Young age at breast cancer diagnosis has been associated with increased risk of recurrence and mortality. We reevaluated this assumption in a large, modern cohort of women diagnosed with breast cancer at age ≤40 years.

Methods: We identified women with breast cancer at age ≤40 years at a single institution from 1996-2008. We assessed locoregional recurrence (LRR), distant recurrence, disease-free survival (DFS), and overall survival (OS), and correlated patient and tumor characteristics with outcomes.

Results: We identified 584 women aged ≤40 years with breast cancer. Median age was 37 years, and median follow-up was 124 months; 61.5 % were stages 0-I and 38.5 % were stages II-III. Overall, 57.4 % had lumpectomies and 42.5 % mastectomies. DFS was 93 % at 5 years and 84.5 % at 10 years. OS was 93 % at 5 years and 86.5 % at 10 years. On multivariate analysis, worse DFS was associated with positive nodes (p = 0.002); worse OS was associated with larger tumor size (p = 0.042). When stratified by lumpectomy versus mastectomy, there were no significant differences in survival or recurrence. For lumpectomy patients, DFS was 96 % at 5 years and 88 % at 10 years; OS was 96 % at 5 years and 89 % at 10 years. For mastectomy patients, DFS was 89.5 % at 5 years and 79 % at 10 years; OS was 90 % at 5 years and 83 % at 10 years. Lumpectomy LRR rates were 1 % at 5 years and 4 % at 10 years. Mastectomy LRR rates were 3.5 % at 5 years and 8.7 % at 10 years.

Conclusions: Outcomes for women with breast cancer at age ≤40 years have improved. Lumpectomy recurrence rates are low, suggesting that lumpectomy is oncologically safe for young breast cancer patients.