strange growth, tumor on a guinea pig

Question
Its located more above the left leg. We are trying antibiotic cream. A crusty top came off, leaving a small hole/cavity below his skin with white material surrounded by the pink skin. Could send photo
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-----Question-----
our guinea pig as a small, strange growth on its hind quarter coming out of the skin. The growth is hard, yellowish/white. It is distinctly seperate from the surrounding pink skin. Some of the growth flaked off, exposing more white material below the skin.
-----Answer-----
Hello Robert,

Where is this growth located exactly? Is it in the area where a tail would be if piggies had tails? And is your Guinea Pig a boy? If the answers are yes and yes, this area is your piggy's grease gland. It is used in marking their territory and sometimes it can create quite a build up. The gland can be cleaned with a soft bristle toothbrush and a bit of baby oil. If the answer to either question is no, I would take the piggy to the vet. It could be a fungal infection or a patch of dry skin (though neither seem very likely) or possibly something entirely different. To be honest, if it isn't his grease gland, I haven't heard of this before. Fungal infection cause areas of dry skin that can weep and get crusty, but not heavyy enough to be called a growth. Dry skin usually just causes dandruff. Is it possible he has gotten something on him? Try soaking the growth in some warm water and see if that helps remove it. Could the growth be hardened pus from an abscess? If none of these sound likely or possible, he should see a vet to have it checked out. Good luck. I'm sorry I couldn't be more helpful.

-kkat
www.geocities.com/abyssinianguineapigs

Answer
Hello Robert,

It sounds most like an abscess or a tumor. If you have pictures that would be great. You can contact me through the address on my website (site address under my name). I would take him to the vet right away. The faster abscesses or tumors recieve treatment the better.

-kkat
www.geocities.com/abyssinianguineapigs