BRCA2 and Klinefelter syndrome: Age, race, family history, obesity, genetic factors (especially BRCA2 mutations), gynecomastia, Klinefelter syndrome, Cowden syndrome, liver diseases that cause an estrogen increase, cirrhosis, ionized radiation and prolonged heat exposure (increases prolactin level) due to environmental factors, alcohol, and excess consumption of red meat are mostly accused in the etiology (1,2,7–9,12,13,17).