Male Breast Cancer
Male breast cancer represents only 1% of all breast cancer diagnosed in the United States. The majority of male breast cancer is diagnosed in individuals who carry the BRCA genetic abnormality.
In men with the BRCA 2 mutation, six in 100 developed breast cancer and in men BRCA1 carriers, one in 100 develop breast cancer.
Other risk factors for male breast cancer are family history, age, Klinefelter Syndrome (XXY), chest wall radiation, liver disease, heavy drinking, obesity and testicular conditions like undescended testis. The majority of patients diagnosed with male breast cancer are in their late 60's, 96% of male breast cancers are estrogen receptor positive.
As far as local therapy in the majority of cases a mastectomy is the treatment of choice instead of lumpectomy because in males there is very little breast tissue.
Locally advanced tumors are treated with neoadjuvant chemotherapy in order to shrink the tumor followed by surgery and radiation.
As far as adjuvant therapy (hormonal and/or chemo) because male breast cancer is uncommon, the treatment recommendations are derived from trials conducted in women.
The Oncotype DX (the 21 gene recurrent score assay) has been useful to evaluate the need for adjuvant chemotherapy in addition to hormonal therapy.
Rarely male breast cancer patients are HER-2-NEU positive and in that instance, like in female patients the monoclonal antibody Herceptin is given in addition to chemotherapy. All male breast cancer patients should be tested for BRCA1 and BRCA2.