Equivalent Survival with Mastectomy or Breast-conserving Surgery Plus Radiation in Young Women Aged < 40 Years with Early-Stage Breast Cancer: A National Registry-based Stage-by-Stage Comparison

Background Studies have shown that young patients with early-stage breast cancer (BC) are increasingly undergoing mastectomy instead of breast-conserving therapy (BCT) consisting of lumpectomy and radiation. We examined the difference in outcomes in young women (aged < 40 years) who had undergone BCT versus mastectomy. Materials and Methods The Surveillance, Epidemiology, and End Results database was queried for women aged < 40 years with stage I or II invasive BC treated with surgery from 1998 to 2003. Breast cancer-specific survival (BCSS) and overall survival (OS) were evaluated using Kaplan-Meier survival analysis and the log-rank test between treatment types. Results Of the 7665 women, 3249 received BCT and 2627 underwent mastectomy without radiation. When separated by stage (I, IIA, and IIB), with a median follow-up duration of 111 months, the BCT and mastectomy-only groups showed no statistically significant differences in BCSS and OS. Overall, the age group of 35 to 39 years (66% of total) was associated with better 10-year BCSS (88%) and OS (86.1%) compared with the younger patients aged 20 to 34 years (34% of total). The latter group had a 10-year BCSS and OS of 84.1% and 82.3%, respectively (P <.001 for both BCSS and OS). However, when the patients of each age group were further subdivided by stage, the BCT group continued to show noninferior BCSS and OS compared with the mastectomy group in all subgroups. Conclusion The results of our study suggest that although young age might be a poor prognostic factor for BC, no evidence has shown that these patients will have better outcomes after mastectomy than after BCT.