Safety, efficacy, and tolerability of systemic therapies in male breast cancer: are there sex-specific differences?

Male Breast Cancer: a Review on Diagnosis, Treatment, and Survivorship

PURPOSE OF REVIEW

Male breast cancer is a relatively uncommon and rare disease that is often managed based on evidence adopted from trials pertaining to female breast cancer due to low accrual rates or exclusion of males. This is despite the known differences in the biology and epidemiology of this condition. This review provides an update regarding the management and surveillance of male breast cancer.

RECENT FINDINGS

Men with breast cancer tend to undergo more extensive surgery in the breast and axilla. The outcomes of male breast cancer compared to a similar subtype of female breast cancer appear worse when matched for stage. Systemic therapies remain predominantly based on recommendations for female breast cancer, although tamoxifen is the more optimal endocrine therapy for men than women. Surveillance with mammograms is recommended for patients harboring a breast cancer susceptibility gene but is otherwise not advised for men who have undergone a mastectomy. Notably, the role of other imaging modalities, including ultrasound and magnetic resonance imaging, is minimal. Although the focus on survivorship care among men is low, it is abundantly clear that this is a stigmatizing diagnosis for men, and they suffer from long-term physical and psychological sequelae following a diagnosis and treatment of breast cancer. In summary, providing more gender-inclusive care and advocating for increased representation of men in prospective breast cancer studies and clinical trials may help improve outcomes and provide enhanced support for this population.

Moderate Intensity Exercise Reduces Side Effects of Cancer Therapy and Maintains Cardiorespiratory Fitness in Male Breast Cancer Patients: Findings from the BRECA Male Crossover Study

Introduction

There is growing evidence that aerobic exercise mitigates cancer therapy-related side effects and improves cardiorespiratory fitness (CRF). However, to the best of our knowledge, no exercise study has been conducted in male breast cancer (MBC) patients. The aim of this study was to investigate the feasibility and efficacy of different exercise intensities on CRF and self-reported questionnaire items in MBC patients.

Methods

Twenty-two MBC patients (60 ± 9 years) participated in this randomized crossover study. After completion of medical treatment, MBC patients were randomly assigned to either moderate (40-50% of heart rate [HR] max. and self-perceived exertion: 11) or vigorous (70-80% of HR max. and self-perceived exertion: 15) exercise intensity during the first 3 months of the study. After a 1-month washout period, participants switched group assignments. Primary endpoints were CRF and questionnaire items.

Results

We observed a dropout rate of 36% over 7 months, with the number of participants decreasing from 22 to 14. The results showed significant improvements in "Physical Function" (p = 0.037) and "Social Function" (p = 0.016) after moderate training. A non-significant improvement was also observed in "Breast Symptoms" (p = 0.095), but there was no change in "Fatigue" (p = 0.306). There were no differences observed in cardiovascular fitness (V̇O2 peak) between the treatment groups.

Conclusion

This study emphasizes the effectiveness of exercise intervention for an exceedingly rare cancer, highlighting the vital role of moderate intensity aerobic exercise in mitigating treatment side effects. Despite minimal peak V̇O2 differences, both exercise protocols adequately sustain CRF. Future studies are imperative to design optimized, sex-specific rehabilitation strategies tailored to the unique requirements of MBC patients, advancing our understanding of this under explored realm.

A practical guide to endocrine therapy in the management of estrogen receptor-positive male breast cancer

The majority (more than 90%) of male breast cancers (MaBCs) are estrogen receptor-positive, such that endocrine therapy is the mainstay of MaBC treatment. Endocrine therapy has been associated with improved overall survival in observational studies on MaBC, though large randomized clinical trials have never been completed to confirm this benefit in this population. Tamoxifen is currently the preferred drug for both metastatic and adjuvant treatment of MaBC. Known differences in treatment patterns and hormonal milieu between men and women may warrant a unique approach to the management of toxicities in men. This review provides a detailed discussion of endocrine therapy for MaBC.