Post Mastectomy Radiotherapy Is Associated With Improved Survival in Node Positive Male Breast Cancer, a Population Analysis

Publication date: Available online 13 February 2017
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Matthew J. Abrams, Paul P. Koffer, David E. Wazer, Jaroslaw T. Hepel
PurposeBecause of its rarity, there are no randomized trials investigating post mastectomy radiotherapy (PMRT) in male breast cancer. This study retrospectively examines the impact of PMRT in male breast cancer patients in the National Cancer Institute's Surveillance Epidemiology and End Results (SEER) database.Methods and MaterialsThe SEER database 8.3.2 was queried for men ages 20+ diagnosed with localized or regional non-metastatic invasive ductal/lobular carcinoma from 1998-2013. Included patients were treated by modified radical mastectomy (MRM), with or without adjuvant external beam radiation. Univariate and multivariate analyses evaluated predictors for PMRT use after MRM. Kaplan-Meier overall survival (OS) curves of the entire cohort and a case-matched cohort were calculated and compared by the log-rank test. Cox-regression was used for multivariate survival analyses.ResultsA total of 1933 patients were included in the unmatched cohort. There was no difference in 5 year OS between those who received PMRT and those that did not (78% vs. 77% respectively, p = 0.371), however, in the case-matched analysis, PMRT was associated with improved OS at 5 years (83% vs. 54%, p=<0.001). On subset analysis of the unmatched cohort, PMRT was associated with improved OS in men with 1-3 nodes positive (5 year OS 79% vs. 72% p=0.05) and those with 4+ nodes positive (5 year OS 73% vs. 53% p<0.001). On multivariate analysis of the unmatched cohort, independent predictors for improved OS were use of PMRT HR=0.551 [0.412-0.737] and ER positive disease HR=0.577 [0.339-0.983]. Predictors for a survival detriment were higher grade III/IV HR=1.825 [1.105-3.015], larger tumor T2 HR=1.783 [1.357-2.342] T3/T4 HR=2.683 [1.809-3.978], higher N-stage N1 HR=1.574 [1.184-2.091] N2/N3 HR=2.328 [1.684-3.218], Black race HR=1.689 [1.222-2.336] and older age 81+ HR=4.164 [1.497-11.582].ConclusionsThere may be a survival benefit with the addition of PMRT for male breast cancer with node positive disease.

Teaser

Because of its rarity, there are no randomized trials providing evidence for or against post mastectomy radiotherapy for male breast cancer. We retrospectively examined its impact via the National Cancer Institute's Surveillance Epidemiology and End Results database. Post mastectomy radiotherapy and estrogen receptor positive disease were found to be an independent predictors of improved survival. Post mastectomy radiotherapy was associated with improved 5-year overall survival in all node positive patients.


http://ift.tt/2lI6AKC