Male Breast Cancer Hormones and Genes

Hormone Receptor Status

The growth of tumors in male breast cancer can be attributed to hormones estrogen or progesterone in nearly 90% of cases. Cancer cells in these tumors have receptors for estrogen called ER-positive, progesterone referred to as PR positive or both. Hormonal therapies will likely work on these tumors as the cancer cells depend on the hormones for growth. An example is tamoxifen, which blocks the estrogen receptor cells in the tumor. 

HER2/neu Status

HER2/neu is a gene that promotes the growth of tumors when activated. It produces a specific growth-stimulating receptor. Patients who have tumors with a high amount of this protein can benefit from Trastuzumab (Herceptin®). This drug works by blocking the growth of the tumor, which is promoted due to the gene. Another drug effective for this is pertuzumab (Perjeta®). There are fewer chances of male breast cancer having HER2 positive tumors compared to females. 

Gene-Expression Profiling

These refer to tests analyzing the tumor at a molecular level. They can be helpful in determining the best treatment plan for each patient.