Pain occurring several months after Mx/Rads

I had Mx in August and Rads in November. I then started GemCarbo chemo as I had a poor response to FEC-T. After the 3rd cycle I have developed severe pain and some swelling in my armpit and generally around that area. It has been suggested to me that it is probably caused by rads damage that has been irritated by the chemo. Has anyone had a similar experience? I have a CT scan and a bone scan booked to check for anything more sinister, but in the meantime the pain is getting worse every day and pain killers are not working. Would really like to hear from anyone who has had a similar experience.

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