I'm growing a breast in my armpit!!

I posted this elsewhere, but now that I have answers am reposting here for others to read.

I'm four months out of treatment (mastectomy, AC and taxotere, proton beam radiation therapy, tamoxifen) for Stage IIIA/Grade 2 at the third best cancer treatment center in the country. 19 out of 42 nodes were positive, and everyone was amazed it hadn't spread. I was left with a "glob" under and slightly posterior to my armpit even though a plastic surgeon opened and closed. Three weeks ago I saw my oncologist and everything looked okay, but the follow-up mammogram had to be rescheduled due to bad weather. Since then, the glob has grown to the size of a pound of ground beef. No pain. Skin looks healthy. No lumps similar to the original tumor which was like a rock. Soft. Rubbery. Feels fluidic in places. I thought lymphedema and sent a photo to my OT who said see the doctor. Now I have a sonogram ordered along with the mammogram. This doesn't feel like what I would expect from a regional recurrence. I've read about fat necrosis. This is exactly like having another boob sprouting out of my armpit. I told the oncologist via portal that it is big enough to qualify for its own mammogram.

Follow-up one week later, and the mass has almost doubled in size... family doctor estimated it at three pounds:

Yesterday I was seen by three specialists, a physical therapist and a sonographer. The giant axillary mass is lymphedema. No metastatic cancer. Now I get to wear a compression bra with an extra compression pad tucked in right over the swelling. Then a wide elastic bandage is wrapped over all of this.... and we are talking TIGHT! Really really right. Plus a compression sleeve and gauntlet which is also wrapped over with an elastic bandage... really really tight.. This actually feels better than it sounds. There's no way to drain because the fluid is diffused in the tissue. I have gone from Mommy to Mummy. But no cancer recurrence! I hope my experience is helpful to someone else. :-)