29-year-old male, left chest pain. What's wrong?

The symptoms of left chest pain in a 29-year-old male may be caused by diseases such as intercostal neuritis and pleurisy, as well as pulmonary diseases such as emphysema, lung cancer and chronic obstructive pulmonary disease. In addition, it cannot be ruled out that it is related to pain caused by diseases such as coronary heart disease and myocardial infarction.