Huge nodular pimple

I'm not positive if this should go in the acne category, but it's my best guess..

My husband has a huge pimple like bump on his shoulder. He has had it for about a year and a half. He popped it once using a needle, which was VERY difficult, and a hard rock like thing came out, and left a small hole in his shoulder. It came back rather quickly, and since then we have not been able to get rid of it again. It's completely painless, and it actually feels like a small rock under the skin. He does not suffer from acne.His skin is very clear, with the occasional comedone on his back. I used to be an esthetician, and I even went to my old school books to try to figure this out, as well as searching the internet. The closest I could come was that it was a boil, only I'm told those are painful, which his is not. Any idea what it could be??

Thanks so much for any help you can provide.

[Bhupinder Kaur, MD]

Hello,

The painless lump that your husband is having seems like a sebaceous cyst. A sebaceous cyst is a closed sac occurring just under the skin which contains a "pasty" or "cheesy" looking substance called keratin.They may occur anywhere on body but scalp, ears, back, face, and upper arm, are common sites for sebaceous cysts. Blocked sebaceous glands, swollen hair follicles,[4] and excessive testosterone production will cause such cysts.

Generally no treatment is required but they become painful then it means they are infected,Then surgical excision by traditional wide excision, minimal excision, and punch biopsy excision may be required.

Hope it helps.Take care and pls do keep me posted in case you have any additional queries.Kind regards.