The different outcomes between breast-conserving surgery plus radiotherapy and mastectomy in metaplastic breast cancer: A population-based study

Background Metaplastic breast cancer (MBC) are rare. The survival outcomes of MBC patients after breast conserving surgery plus radiotherapy (BCS+RT) or mastectomy have not been established. The study aimed to compare survival outcomes of MBC patients subjected to BCS+RT or mastectomy therapeutic options. Methods Patients who were subjected to BCS+RT or mastectomy between 2004 and 2014 were enrolled in this study through the Surveillance, Epidemiology and End Results (SEER) database. Breast cancer-specific survival (BCSS) and the overall survival (OS) of the participants were determined. Cox proportional hazard model and the Kaplan Meier method were used to determine the correlation between the two surgical methods and survival outcomes. Results A total of 1197 patients were enrolled in this study. Among them, 439 patients were subjected to BCS+RT, while 758 patients were subjected to mastectomy. After propensity score matching (PSM), the BCS+RT and mastectomy groups consisted of 321 patients, respectively. The univariate and multivariate analysis with a 6-month landmark all indicate that patients receiving BCS+RT has higher OS than patients receiving mastectomy (HR = 0.701,95% CI = 0.496-0.990, P = 0.044; HR = 0.684,95% CI = 0.479-0.977, P = 0.037) while the BCSS was no difference between the two groups (HR = 0.739,95% CI = 0.474-1.153, P = 0.183; HR = 0.741,95% CI = 0.468-1.173, P = 0.200). Conclusion The BCS+RT therapeutic option exhibits a higher OS in MBC patients compared to the mastectomy approach.

Automated summary

The study compared the survival outcomes of metaplastic breast cancer (MBC) patients who underwent breast conserving surgery plus radiotherapy (BCS+RT) or mastectomy. It was found that BCS+RT resulted in higher overall survival rates compared to mastectomy, while there was no difference in breast cancer-specific survival rates between the two surgical methods.