TBH I really don't know but one thing I do know is if I feel like something isn't right I won't stop until I get an answer. I never received any lumps after radiation. If I were you I would definitely get a second opinion. Maybe see your PCP or OBGYN. One of my lumps I'm concerned about is near the axilla. I am going to ask for an MRI or biopsy. I want to know for sure.

I did have both my underarms break out and I was told it was a fungal infection and it itched but yours does not sound like that. I would get any lumps checked out. Please keep me posted and I wish you the best. My email is tracimoore1@yahoo.com if you'd like to email me any further.