I'm a 49 year old male with chest, rib, and armpit pain for 5 weeks. I've had two visits to a general practitioner and got chest x-ray, blood work, and ekg. The general practitioner says it's Costochondritis. My father died of lung cancer at 59, brother of colon cancer at 52. I'm thinking of having a low dose ct of my chest to be sure. What's your opinion?