My 20 Year Old Daughter Is Experiencing Pain In Her

My 20 year old daughter is experiencing pain in her back just above the top of the bra. The pain radiates to the left shoulder, down her left arm and into her hand. She says it is an achy pain - like a toothache.
She did have Hodgkins Lymphoma at 16 and has been in remission 3 years (has 6 month checkups). I cannot feel a lump or anything around the painful area on the back but it is very painful for her when I touch it. Is this something she needs to be seen for immediately or should we use heat and ice and ibuprofen and see what happens? Thanks.