Trends, survival outcomes, and predictors of nonadherence to mastectomy guidelines for nonmetastatic inflammatory breast cancer.

Abstract

The Current National Comprehensive Cancer Network guidelines recommend modified radical mastectomy (MRM) as the surgical treatment of choice for nonmetastatic inflammatory breast cancer (IBC). Limited studies have looked into the outcomes of breast conserving surgery (BCS) vs. MRM for IBC. National Cancer Database (NCDB) data from 2004 to 2014 were retrospectively analyzed. Patients' demographics, tumor characteristics, and overall survival (OS) trends were compared for BCS and MRM cases of nonmetastatic IBC. Univariate and multivariate analyses were performed. A total of 413 (3.89%) BCS and 10,197 (96.11%) MRM cases were identified. Median follow-up was 58.45months. Compared to MRM, BCS patients were more likely to be older, be African American, have Medicare/Medicaid or be uninsured, live in lower education ZIP codes, and live in a metropolitan area (all p<0.05). BCS rates significantly decreased from 5.84% in 2004 to 3.19% in 2014 (p<0.001). BCS patients also were more likely to have less than 50% of the breast involved (51.57% vs. 43.88%; p=0.0081) and were less likely to receive trimodal therapy (50.85% vs. 74.62%; p=<0.0001). The OS was significantly higher in the mastectomy group over 9years at 62.02% vs. 54.47% in the BCS group. Additionally, in the adjusted multivariate model, BCS cases were associated with 23% higher hazards of overall mortality (p=0.0091). BCS was performed in a limited number of cases, which decreased over the study period. The analysis identified both demographic predictors of receiving BCS and significantly lower OS for IBC patients undergoing a BCS.