Question: What is (are) Male Breast Cancer ?
Answer: Key Points - Male breast cancer is a disease in which malignant (cancer) cells form in the tissues of the breast. - Radiation exposure, high levels of estrogen, and a family history of breast cancer can increase a mans risk of breast cancer. - Male breast cancer is sometimes caused by inherited gene mutations (changes). - Men with breast cancer usually have lumps that can be felt. - Tests that examine the breasts are used to detect (find) and diagnose breast cancer in men. - If cancer is found, tests are done to study the cancer cells. - Survival for men with breast cancer is similar to survival for women with breast cancer. - Certain factors affect prognosis (chance of recovery) and treatment options. Male breast cancer is a disease in which malignant (cancer) cells form in the tissues of the breast. Breast cancer may occur in men. Men at any age may develop breast cancer, but it is usually detected (found) in men between 60 and 70 years of age. Male breast cancer makes up less than 1% of all cases of breast cancer. The following types of breast cancer are found in men: - Infiltrating ductal carcinoma: Cancer that has spread beyond the cells lining ducts in the breast. Most men with breast cancer have this type of cancer. - Ductal carcinoma in situ: Abnormal cells that are found in the lining of a duct; also called intraductal carcinoma. - Inflammatory breast cancer: A type of cancer in which the breast looks red and swollen and feels warm. - Paget disease of the nipple: A tumor that has grown from ducts beneath the nipple onto the surface of the nipple. Lobular carcinoma in situ (abnormal cells found in one of the lobes or sections of the breast), which sometimes occurs in women, has not been seen in men. Men with breast cancer usually have lumps that can be felt. Lumps and other signs may be caused by male breast cancer or by other conditions. Check with your doctor if you notice a change in your breasts.
Source: CancerGov

Question: How to diagnose Male Breast Cancer ?
Answer: Tests that examine the breasts are used to detect (find) and diagnose breast cancer in men. The following tests and procedures may be used: - Physical exam and history : An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patients health habits and past illnesses and treatments will also be taken. - Clinical breast exam (CBE): An exam of the breast by a doctor or other health professional. The doctor will carefully feel the breasts and under the arms for lumps or anything else that seems unusual. - Ultrasound exam: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. The picture can be printed to be looked at later. - MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI). - Blood chemistry studies : A procedure in which a blood sample is checked to measure the amounts of certain substances released into the blood by organs and tissues in the body. An unusual (higher or lower than normal) amount of a substance can be a sign of disease. - Biopsy : The removal of cells or tissues so they can be viewed under a microscope by a pathologist to check for signs of cancer. The following are different types of biopsies: - Fine-needle aspiration (FNA) biopsy : The removal of tissue or fluid using a thin needle. - Core biopsy : The removal of tissue using a wide needle. - Excisional biopsy : The removal of an entire lump of tissue. If cancer is found, tests are done to study the cancer cells. Decisions about the best treatment are based on the results of these tests. The tests give information about: - How quickly the cancer may grow. - How likely it is that the cancer will spread through the body. - How well certain treatments might work. - How likely the cancer is to recur (come back). Tests include the following: - Estrogen and progesterone receptor test : A test to measure the amount of estrogen and progesterone (hormones) receptors in cancer tissue. If cancer is found in the breast, tissue from the tumor is checked in the laboratory to find out whether estrogen and progesterone could affect the way cancer grows. The test results show whether hormone therapy may stop the cancer from growing. - HER2 test: A test to measure the amount of HER2 in cancer tissue. HER2 is a growth factor protein that sends growth signals to cells. When cancer forms, the cells may make too much of the protein, causing more cancer cells to grow. If cancer is found in the breast, tissue from the tumor is checked in the laboratory to find out if there is too much HER2 in the cells. The test results show whether monoclonal antibody therapy may stop the cancer from growing.
Source: CancerGov