Key clinical point: Tamoxifen treatment is associated with improved disease-free survival (DFS) in male breast cancer (MBC) patients.

Major finding: Patients who did not receive tamoxifen had a significantly reduced DFS compared with those who received tamoxifen (P = .002). Tamoxifen recipients had a lower rate of recurrence or death vs. those not receiving tamoxifen (13.9% vs. 22.6%). After adjustments, tamoxifen reduced the recurrence rate by 62%.

Study details: This prospective cohort analysis included 448 patients with MBC using data from the German national prospective cancer registry.

Disclosures: This study did not receive any funding. The authors declared no conflicts of interest.

Commentary

Approximately 1% of all breast cancers occur in males. General treatment principles are extrapolated from predominantly female-populated trials. Tamoxifen reduces risk of recurrence and breast cancer mortality in early-stage hormone receptor (HR)-positive breast cancer, and this current study highlights the benefit seen with tamoxifen in males. Side effects of tamoxifen in males include weight gain, vasomotor symptoms, erectile dysfunction and venous thromboembolism. Discontinuation rates of tamoxifen are high in males, which may adversely affect outcomes, and strategies are needed to improve adherence. Contrary to what is seen in females, aromatase inhibitors (AIs) are associated with worse survival rates compared to tamoxifen in males. This finding may be driven by physiologic differences and testicular production of estrogen that cannot be suppressed with an AI alone. Addition of a gonadotropin-releasing hormone agonist (GnRHa) helps overcome this issue, and AI plus GnRHa combination can be considered as an alternative treatment option in males.

Erin Roesch, MD

The Cleveland Clinic

References:

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