Hi, Welcome to Health care magic forum.
The pain may not have any relation to the breast cancer
. First thing to be seen for it is the lump, butnot the pain. It may be some thing of the sputum in the chest, or may be the muscular pain
I advise you to consult a physician for diagnosis and treatment.
Take more of green leafy vegetables, pulses, sprouts,and
protein rich foods to hasten the recovery.
Wishing for a quick and complete recovery. Thank you.