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Testicular Cancer

22 10:19:22

Question
Hi, Dana --
I wrote to you recently about our bunny who has spondylosis, but this week we found out that her bonded buddy, Max, (who had to have his eyes removed last year, due to glaucoma) has/had testicular cancer.  This came as quite a shock because we had him neutered 6 years ago, when we adopted him.  (For other reasons, we've since switched vets, and our current vet has lots of rabbit experience.)  Anyway, we took him in because we kept finding that his arm and belly fur were damp and "crunchy".  We thought he had dental problems, but the vet felt a mass in his abdomen and, on the x-ray, it looked pretty large.  She did surgery yesterday, and was surprised to find that Max had undescended testicles with bilateral testicular tumors.  The vet removed them and, she seemed pretty happy about this diagnosis, telling us that testicular cancer in rabbits rarely spreads.  I've been looking around for some stats on this and haven't been able to find much.  Do you have any info on the rate of metastasis or recurrence of testicular cancer in bunnies?  The vet felt pretty confident that she'd removed both tumors completely and said that they "looked clean," but I know in humans testicular cancer can seed throughout the abdomen fairly easily.
Sorry that this is kind of a nitpicky question, but this little guy has been through so much, and I've learned to really do my research with his health problems (or, in this case, to try to get someone with better resources to do my research for me.)  I really appreciate that you take the time to answer these questions so thoughtfully!  
Thanks
Leah

Answer
Dear Leah,

Oh, MAN.  Poor bunny!  And shame on that other vet for not being straight with you about the cryptorchids (undescended testicles), which are *very* likely to become cancerous if not removed.  I'm glad you have a good vet who knew what to do.

I have to tell you the truth:  this is SO uncommon in rabbits, at least so far, that I have never heard of it.  Pampered house rabbits are usually neutered, so it's not an issue.  Rabbits in hutches or outdoors often just don't live long enough to develop this problem.  Cryptorchids are not all that common to begin with.

That said, we *have* had rabbits with testicular cancer, and once they were neutered there was no recurrence of the cancer.  I would trust your vet if she thought the tumors seemed encapsulated and were completely removed.  But at this point in rabbit medicine's history, there are just not enough data available on this to give you any type of statistical chance of recurrence.  So it's hope for the best, and consider your boy a sample size of one.  Please *do* share his medical results as they develop, though.  His is truly an unusual case, and the more we learn from such unusual cases, the better we'll be able to deal with them when they are more commonly diagnosed in the future.

The only other thing I'd suggest is that you, at least temporarily, join EtherBun and share your little guy's saga there. The listserve has over 5000 rabbit-loving members, and there are no doubt some who have had experience with rabbit testicular cancer and can share it with you.

You can learn more about Etherbun and join here:

www.bio.miami.edu/hare/etherbun.html

I'm glad the surgery went well, and I hope this is truly the end of the cancer for Max.  

Take care,
Dana