Cancer mastectomy, Breast reconstruction 5 years ago. Terrible itching under epidermis.

You should definitely see your PCP or the surgeon who did your mastectomy just to make sure that nothing worrisome is going on. You can develop chronic pain with implant based reconstruction. If that is what you are experiencing, you may want to consider autologous reconstruction (i.e. DIEP free flaps).

You should first see your primary doctor and maybe you breast cancer surgeon to be evaluated. The breast cancer surgeon can also refer you to a plastic surgeon. Best of luck.