The role of postoperative radiation therapy in stage I–III male breast cancer: A population-based study from the Surveillance, Epidemiology, and End Results database

by Peiwen Wu, Dongjie He, Shuchai Zhu, Hao Chang, Qiming Wang, Qiuju Shao, Gaiyan Li 

The Breast: Published: June 22, 2022

 

Background

This study aimed to investigate the role of adjuvant radiation therapy in a large population-based cohort of patients with stage I–III male breast cancer (MaBC).

Methods

Patients with stage I–III breast cancer treated with surgery were selected from the Surveillance, Epidemiology, and End Results cancer database from 2010 to 2015. Multivariate logistic regression identified the predictors of receiving radiation therapy. Multivariate Cox regression model were used to evaluate the predictors of survival.

Results

We identified 1321 patients. Age, stage, positive regional nodes, surgical procedure, and HER2 status were strong predictors of radiation therapy administration. There was no difference between patients who received radiation therapy and those who did not (P = 0.46); however, after propensity score matching, it was associated with improved OS (P = 0.04). In the multivariate analysis, the factors associated with better OS were administration of radiation therapy and chemotherapy. In the subset analysis, adjuvant radiation therapy was associated with improved OS in men undergoing breast-conserving surgery (BCS), with four or more node-positive or larger primary tumours (T3/T4). Furthermore, we found no benefit of radiation therapy, regardless of the type of axillary surgery in mastectomy (MS). In older MaBC patients with T1-2N1 who underwent MS, radiation therapy showed no significant effects, regardless of chemotherapy.

Conclusion

Adjuvant radiation therapy could improve the survival of MaBC patients undergoing BCS, with four or more node-positive or larger primary tumours. Moreover, it should be carefully considered in patients undergoing MS and older T1-2N1 patients.

 

Relevance of the 21-gene expression assay in male breast cancer: A systematic review and meta-analysis

 

by Matthew G. Davey, Ciara M. Davey, Luis Bouz, Eoin Kerin, Carson McFeetors, Aoife J. Lowery, Michael J. Kerin 

 

The Breast: VOLUME 64, P41-46, AUGUST 01, 2022 (Published: April 28, 2022)

 

Introduction

The 21-gene assay provides prognostication for estrogen receptor positive, human epidermal growth factor receptor-2 negative (ER+/HER2-) early female breast cancer patients. This signature has not been validated in male breast cancer (MBC).

Methods

A systematic review and meta-analysis was performed in accordance to the PRISMA guidelines. Retrospective cohort studies comparing 21-gene assay scores in female and MBC were included. Dichotomous variables were pooled as odds ratios (OR) and associated 95% confidence intervals (CI) using the Mantel–Haenszel method.

Results

Six studies including 176,338 patients were included (mean age of 63.4 years, range: 33–88). Of these, 1.0% had MBC (1826/176,338) and 99.0% were female patients (174,512/176,338). MBC patients were more likely to have increased tumour stage, nodal involvement, and grade 3 disease (all P < 0.001) In MBC patients, the mean score was 18.8 (range: 11–26) vs. 13.4 (range 0–33) in female patients (P < 0.001). In MBC patients, 22.4% had scores >30 (408/1822) versus 18.3% in female patients (31,852/174,500). In female patients, 52.0% had scores <18 (90,787/174,500) versus 47.8% in MBC (471/1822). Overall, patients with female patients were as likely to have scores <18 (OR: 1.04, 95% CI: 0.94–1.16), scores 18–30 (OR: 1.12, 95% CI: 1.00–1.26) and scores >30 (OR: 0.69, 95% CI: 0.45–1.07) as MBC patients.

Conclusion

There are similar anticipated scores for female and MBC undergoing 21-gene expression assay testing for early stage, ER+/HER2-breast cancer. In the absence of stage matching, cautious interpretation of these results is required. Validation of the 21-gene assay in MBC is still required.

Keywords