There are physiological and pathological reasons for chest heating and swelling.1. The physiological reason is that males will experience chest heating and swelling symptoms during puberty. This is normal, and it will improve significantly after a period of time or is mostly a cyclical symptom. 2. Pathological causes are mainly due to mammary gland hyperplasia, mastitis, breast cancer, etc. Mammary gland hyperplasia is an abnormal enlargement of breast tissue caused by endocrine hormone imbalance, often accompanied by breast swelling and pain, fever, nipple overflow and other symptoms. Mastitis is a localized inflammation of the breast caused by bacterial infection, with swelling, redness, pain and fever as the main manifestations. Breast cancer mainly develops in women before and after menopause. In the middle and late stages, there will be swelling and pain, pressure pain and breast lumps.