Hi @dick61 and @deebee41, here are some research papers specifically about men and tamoxifen:
- Management of Male Breast Cancer: ASCO Guideline https://ascopubs.org/doi/10.1200/JCO.19.03120
- Survival benefit of tamoxifen in male breast cancer: prospective cohort analysis https://www.nature.com/articles/s41416-020-0857-z
- Tamoxifen in men: a review of adverse events https://pubmed.ncbi.nlm.nih.gov/27152880/

There is earlier research as well that establish tamoxifen as safe and effective in men with breast cancer.