Impact of Bilateral Versus Unilateral Mastectomy on Short Term Outcomes and Adjuvant Therapy, 2003–2010: A Report from the National Cancer Data Base

Rates of bilateral mastectomy (BM) have increased, but the impact on length of stay (LOS), readmission rate, 30-day mortality, and time to adjuvant therapy is unknown.

Using the National Cancer Data Base, we selected 390,712 non-neoadjuvant AJCC stage 0–III breast cancer patients who underwent either unilateral mastectomy (UM) or BM from 2003 to 2010 with and without reconstruction. We used chi-square and logistic regression models for the analysis.

A total of 315,278 patients (81 %) had UM, and 75,437 (19 %) had BM; 97,031 (25 %) underwent reconstruction. The number of median days from diagnosis to UM increased from 19 days in 2003 to 28 days in 2010, and for BM, increased from 21 to 31 days (p < 0.001). BM was independently associated with a longer time to surgery when adjusting for patient, facility, and tumor factors and reconstruction (OR 1.11; 95 % CI 1.07–1.15; p < 0.001). Reconstructed patients were twice as likely to have a longer time to surgery (OR 2.07; 95 % CI 2.01–2.14; p < 0.001). The median LOS was 1 day (range 0–184 days) for UM versus 2 (range 0–182) for BM (p < 0.001); 30-day mortality and readmission rates were not different between BM and UM. The median number of days from diagnosis to definitive chemotherapy, hormonal therapy, and radiation therapy was significantly greater in the BM group.

Delays to surgical and adjuvant treatment are significantly longer for BM irrespective of reconstruction, and these delays have increased over the study period. These findings can be used by clinicians to counsel patients on BM.