Hi. Your condition could be lymphedema, but it could also be post-mastectomy pain syndrome. I'm giving you the addresses of two websites which give excellent information about this.
http://www.cancersupportivecare.com/neuropathicpain.php
http://www.cancerlynx.com/mastectomypain.html
Hello Brendat,
Lymphedema is common among post mastectomy patients and becomes still worse following radiotherapy. Probably it could be lymphedema, but swelling in the forearm and hand would be present sometimes to the extent of whole limb is involved.