I saw my Oncologist NP - I had a CT scan it was determined benign. I was told it is scar tissue.
It still continued to get larger, I called my Breast Cancer surgeon. Saw her last week she looked at the scan photos and actually spoke w the radiologist that read the scan. She also did a ultra sound on me during the visit and did a full exam. She told me the scar tissue is in a muscular area thats causing pressure and edema. I have a lot of muscle mass, it is in a area where I had radiation burn.
Im doing some occupational therapy. This may help loosen the area up and help.
In your case I would see your oncologist and make sure everything is ok, nothing to worry about.

Thank you

I have the same thing.