I have had a sharp pain in the left side of my chest for several weeks now. it is located just over my heart. i have been smoking for the past 15 years and i am very concerned about cancer which runs in my family. i exercise four to five times a week for

This : This sharp pain on the left side of chest could be from your lungs, heart or mediastinum. It is possible that it is lung cancer or pulmonary embolism. I would reccommend that you get lab work of d dimer, and chest xray to start. If there is either abnormal, then a ct scan of chest with contrast. If the chest pain were dull, i would reccommend a stress test and echo cardiogram. Sharp pains may more likley be from lung or pleura.

Sharp pains: Can be from a collapsed lung or pleurisy...Start with a chest x-ray, and this warrants an er visit. But how on earth can you continue to smoke with what you told us? Quit.