Hello, I'm sorry to hear about your friend's bunny and I'd like to help.
There are a couple reasons to have multiple under the skin nodules that are uncomfortable to the touch. The good news it that with multiple lumps cancer or a tumorous cause is unlikely.
The two most common causes are abscesses under the skin, usually due to a pasteurella infection or an infestation with cutrebra or bot fly larvae.
Pasteurella is a bacterial infection that is endemic (meaning it is always found even if not all bunnies appear sick) in some rabbitries. It can cause upper respiratory infection symptoms, pneumonia, eye infections, oral infections and abscesses, lymph node infections and abscesses under the skin. Once a bunny has the bacteria it is virtually impossible to get rid of it completely. We treat flareups appropriately depending upon the symptoms. That may include eye drops, oral or injectable antibiotics, and surgical removal of abscesses. Rabbits have inspissated or dry cheesy, purulent debris, so abscesses cannot be simply lanced and drained they must be curetted out or better yet removed entirely.
Bot flies or cuterebra are flies that lay their eggs near rabbit dens or cages. The larvae emerge, get into the bunny through the oral cavity or nasal passages and travel to various spots in the body, normally settling just under the skin so the larvae can emerge when mature through a breath hole. In some cases the larvae can travel to other spots such as the brain or spinal cord or into the abdomen or lungs and cause serious problems. The larvae must be removed via a quick surgery as if we attempt to remove them via their breath holes and the larvae ruptures that can lead to a horrible anaphylactic type reaction.
What sort of lab testing was done?
Was it an aspirate or biopsy of one of the lumps? If so that should give a diagnosis and direction on therapy.
In the meantime I would look for breath holes associated with the lumps. Here are some pictures:
Make sure the bunny continues to eat well as either one of these disease processes burn lots of calories.
Please let me know if you have any further questions.
Thanks for the further information.
Once the eggs are laid and the bots get in the bunny there is nothing to be done except remove them as they pop up.
By quick surgery I mean opening up the breathing hole wide enough that the bot can quickly be removed without breaking the bot as the fluids inside the bot released into the bunny's subcutaneous tissues will cause a horrible reaction. It doesn't mean removing the entire lump via surgery. Once the bot is gone, and the wound is flushed the reaction will go away. So the procedure is very quick on each spot. There isn't any medication that works to kill the bot, and even if we had one the bot dying in the bunny would lead to a very bad reaction to the foreign material decomposing.
The flies come in, lay their eggs and leave to die very quickly. They don't eat as adults, so unlike the typical fly they do not hang around and the adults are rarely seen.
Prevention is using fine cage screening so the flies cannot get in to lay eggs. You can also use a pyrethrin based area treatment around the cage to kill the adult flies.
I can help you find a veterinarian that can help your friend's bunny.
Certainly the veterinary school in Raleigh should have a veterinarian at the small animal clinic that would be able to help you.
If not here is a link to a list of veterinarians with plenty of experience with rabbits:http://www.trianglerabbits.org/health/vet.html
Best of luck with this little one, please let me know how things go, thanks, XXXXX XXXXX
I am very, very sorry to hear about your friend's bunny's biopsy results.
Lymphoma is not very common in rabbits but when we skin lesions there are almost always lesions internally as well, involving the spleen, internal lymph nodes and liver. It is seen much more commonly in bunnies in Europe then in Northern America although we aren't certain why.
Treatment is fairly unrewarding as far as I know although your friend may wish to consult with a veterinary oncologist for the latest recommendations.
I am so sorry to hear that this wasn't a more treatable disease process.