Mammary tumor?

Question
QUESTION: My pet bunny Mina is a 10 year old unspayed female.  I'm
unsure of her breed, but she has never gotten to be over 3
or 4 pounds, and is quite small, so I suspect she is a dwarf
breed.

A few days ago, I found a large, almost golf-ball sized,
oddly-shaped lump on her chest, under her nipple, which
seems to be almost dangling off her body rather than
completely under the skin.  One part of it was bloodied and
oozing a bit, as though she had been biting at it.  I took
her to the vet, and he said he suspects it is a tumor, but
he did not biopsy it.  He said if it's a tumor, that surgery
was the only option for a long term solution, but that he
did not recommend surgery because of her age.  For now, we
are trying a week of antibiotics to see if the lump is
possibly just an infection of some sort.  In the meantime,
I've been told to keep the lump covered with triple
antibiotic ointment and a bandage to keep her away from
biting at it.

I understand that she is considered elderly and that there
is increased risk for surgery.  However, she has always been
a very healthy rabbit, and still remains active, friendly,
and is eating/drinking/defecating normally.  If not for the
lump, you would think there is nothing wrong with her.  The
vet's suggestion made me feel like this is a death sentence,
but I have read stories of even elderly bunnies recovering
from surgery well and living for a few more years.  I'm
unsure what to do, and want to be well-informed before I
make a decision.  I have an appointment to see another vet
for a second opinion, and I thought it'd be useful to get
one here as well.

Thank you so much for any help you can offer!



ANSWER: Dear Jennifer,

If the lump is really hanging very loosely, and is not attached to underlying tissue, I wonder if you might be able to find a vet who would be willing to remove it quickly under local anesthesia.  This will not be possible if the lump is well attached via a large amount of skin.  But I can't see it, so am offering this wildcard suggestion.

You might wish to consult another rabbit vet:

www.rabbit.org/vets

to see if any would be willing to do bloodwork and assess her health and possible candidacy for surgery.  The lesion is likely painful if it is cancer, and should be removed.  Many rabbits of her type live well into their teens, and I'd hate to think that leaving it there to metastasize would cut her life short.

Another vet might also want to radiograph her chest to be sure the cancer has not spread there.  If it has, then surgery would not be recommended, except perhaps the debulking of the visible tumor under local anesthesia.

I hope this helps.

Dana

---------- FOLLOW-UP ----------

QUESTION: Dana,

Thanks so much for your answer.  Unfortunately, her lump
seemed to have grown over the span of a few days, and I was
too nervous to wait any longer.  I went ahead and got her
the surgery, and she came through today.  I'm just waiting
to get off work now so I can go pick her up and bring her
home and spoil her!

The vet said that during the surgery he found another lump--
a very small one deeper under the skin on the other side of
her chest--and removed that one while he was in there.  We
get the biopsy results in a week, and are hoping for a clean
bill of health.  I thought I'd post this follow-up response
to you in case you had additional advice to offer, as well
as to give some hope to anyone else who might read this.  

I understand the lump may be a cancerous tumor, or may have
been an abscess (the vet does think this is possible).  What
can I expect with either diagnosis?  

Answer
Dear Jennifer

If it grew that quickly, it's quite possible that it was an abscess.  That would be easy to check:  if the vet cuts into it, it will be a big, gross ball of pus.  That would actually be better than cancer, since a culture and sensitivity test could be done from a sample of the abscess capsule wall, and appropriate antibiotics prescribed.

If it's cancer, you just have to hope it hasn't gone any farther.  I am glad the surgery went well, and that she's recovering.  Lots of healing vibes to your bunny baby!

Dana