Lump under armpit

My sister noticed a small lump under her armpit several months ago. She had her doc look at it, she felt it and said its a cyst. That was that. Now last night, it started becoming painful, and she felt it and she said it was larger. Its under her skin inside. Anyone ever have this? Shes nervous its cancer, but I read cancer lumps under the armpit are typically painless. She is calling a dermatologist in the morning to have it either looked at or biopsied. Any experience with this?

This page is a permanent link to the reply below and its nested replies. See all post replies »

Panda5689 · M

Cancer survivor and health care professional here. Return to the doc sooner than later and have it re-checked and possible referral out for more review. If its growing and becoming an issue better find out what it is. I had a lump on my neck. Appeared on palpation and observation as benign. MRI revealed nothing to worry about. Surgical excision found it to be squamous cell carcinoma ... 7 weeks of radiation / high dose platinum based chemo ie 7 weeks of hell and cured. So I may be a bit over reactionary however the ENT docs and oncologists were spot on with it.
And from the day I got the Dx to the f/u PET scan revealed cancer free I stayed away from my resources, google and played dumb and became 100 %.

Coralmist · 41-45, F

@Panda5689 Wow to think they found it was cancer AFTER removing it...so glad you feel better and are cured of it. My sister has an ultrasound this week or x ray, so HOPEFULLY it will be benign🥺

Panda5689 · M

@Coralmist Good to hear. Best to rule out the worst. It is scary af, however, got to be positive