I am trying to find out what is the cause of pain on my arm. I had a mastectomy with lymph node clearance 9 months ago followed by chemotherapy and radiation. I now have lymphoedema in my arm. I finished radiation 4 weeks ago. The pain in my arm is getting worse with last night a shooting pain in my thumb joint. I needed to take pain killers. After radiation my chest and arm pit are very tight. I have read the pamphliets given to me about radiation side effects and it does mention that 1% pf patients develop pain in their arm. Has anyone else experienced this pain and will it go away? Or does lymphoedema cause pain? I also have lymphoedema in my right leg which developed 12 years after groin node clearance and I don't have this type of pain in my leg. (I suspect the delayed leg lympoedema was triggered as result of chemo for my breast cancer.