In men, pain under the nipple, reddening of the skin and local edema are considered to be caused by inflammatory infections. If the skin is not reddened and there is no local edema, other causes should be excluded. If there is a lump under the nipple, it should be ruled out as a result of breast enlargement or breast tumor. If there is no abnormality in the breast area, pressure pain at the rib cage may be caused by costochondritis, mostly accompanied by pain when lowering the head, which is persistent and vague. If the pain below the left nipple is accompanied by chest tightness, palpitations and shortness of breath, it is necessary to exclude that it is caused by heart diseases, such as pericarditis, angina pectoris and myocardial infarction. If the pain below the nipple is accompanied by coughing and coughing, it may be caused by pneumonia or pleurisy. If there is unilateral radiating pain below the nipple, it is caused by intercostal neuralgia.