Breast cancer is widely seen as a disease that affects only women, but men can develop it as well. Male breast cancer accounts for less than 1% of all breast cancer cases. Because awareness of the disease is limited, however, diagnosis is often delayed. Doctors warn that lumps in the chest are sometimes dismissed as gynecomastia, a benign enlargement of breast tissue.
Men and women are born with essentially the same breast structure, and men also have mammary tissue including milk ducts, which means breast cancer can occur, according to Kyung Hee University Hospital on the 18th. In women, mammary and fatty tissue develop after puberty under the influence of female hormones, while development in men is comparatively limited.
"Male breast cancer tends to be diagnosed at a relatively late age, mostly in the 60s and 70s," said Chae Su-min, a professor of breast surgery at Kyung Hee University Hospital. "Beyond advanced age, a family history of breast cancer, BRCA2 gene mutations, radiation exposure, obesity and changes in the sex hormone environment can also act as major risk factors."
The most common symptom of male breast cancer is a lump in the chest. But the symptoms resemble those of gynecomastia, making the two difficult to distinguish. Gynecomastia is a condition in which mammary tissue beneath the nipple and areola enlarges. Such lumps often feel soft or elastic to the touch and are frequently accompanied by pain. They usually appear symmetrically in both breasts, though they can occur on only one side.
Male breast cancer, by contrast, is typically found as a hard lump that does not move easily, located beneath or near the nipple on one side. It often causes no pain, making it easy to brush off as unimportant.
"It is difficult to judge on your own whether a lump is cancer based only on how it feels or whether it hurts," Chae said. "If a lump is accompanied by bloody nipple discharge, nipple retraction, skin changes that resemble an orange peel or swollen lymph nodes in the armpit, the possibility of breast cancer should be checked."
Men have less breast tissue than women, so when cancer develops it can more easily invade surrounding structures such as the nipple, skin and chest wall. If any new change appears in the chest area, it is important to visit a medical institution for examination.
Surgery is the primary treatment for male breast cancer, and total mastectomy is most commonly performed. Depending on the location and extent of the tumor, however, breast-conserving surgery and radiation therapy can be considered. Chemotherapy, endocrine therapy and targeted therapy may also be used in combination, depending on how far the cancer has progressed and its characteristics.
A high proportion of male breast cancers are hormone receptor-positive, which makes endocrine therapy after surgery an important part of treatment. Tamoxifen, which suppresses the action of female hormones, is among the drugs commonly used.
"Male breast cancer has a high rate of hormone receptor-positive cases, in which cancer cells proliferate under the influence of female hormones," Chae said. "Adjuvant endocrine therapy that minimizes hormonal stimulation after surgery plays a key role in lowering the risk of recurrence."
Male breast cancer also has a relatively good prognosis when detected early. If diagnosis is delayed, however, the risk of spread to nearby lymph nodes or other organs rises.
"Men who are in their 60s or older, or who have risk factors such as a family history of breast cancer or gene mutations, should watch for changes in the chest area carefully and consult a specialist if they notice anything unusual," Chae said. "Men who carry high-risk genetic factors in particular should undergo genetic testing through genetic counseling and set up a screening plan tailored to the results."
