I have a lump above my left collarbone about the size of a walnut. It s palpable and visible. People ask about it. It s not painful, red or warm. It s been there about 6 months or so. I m a 19 year breast cancer survivor, diagnosed at age 25. Stage IIB (right side), no lymphnode involvement. Chemo, radiation, bilateral mastectomies. ER/PR negative. I m currently still pre-menopausal. I have a doc appt coming up in 2 weeks but am very nervous... any idea what this could be?