I had a lumphectomy on my left breast two years ago for cancer and had radiation therapy and treatment only. About 4 months after surgery, my breast became very sore underneath and under my arm. On examination, they told me I had something in the breast but they could not see through it to the tissue underneath. Since then I changed doctors and he completely ignored my request for some answer if possible. What could it be and how can I get treatment if necessary. I have since changed doctors and could not schedule an appoint until sometime in March.