Male Breast Cancer

Breast cancer in men is a rare disease. Less than 1% of all breast cancers occur in men. In 2005, when 211,400 women were diagnosed with breast cancer in the United States, 1,690 men were diagnosed with the disease.

You may be thinking: Men don't have breasts, so how can they get breast cancer? The truth is that boys and girls, men and women all have breast tissue. The various hormones in girls' and women's bodies stimulate the breast tissue to grow into full breasts. Boys' and men's bodies normally don't make much of the breast-stimulating hormones. As a result, their breast tissue usually stays flat and small. Still, you may have seen boys and men with medium-sized or big breasts. Usually these breasts are just mounds of fat. But sometimes men can develop real breast gland tissue because they take certain medicines or have abnormal hormone levels.

Because breast cancer in men is rare, few cases are available to study. Most studies of men with breast cancer are very small. But when a number of these small studies are grouped together, we can learn more from them.