Q. My 8-year-old Bernese mountain dog has a mast cell tumor in the skin of her tail, about an inch from the tail’s base. Because there is so little skin on the tail, it’s hard to get optimal margins when removing a mast cell tumor there — wide-enough margins would leave too little skin to close up where the tumor had been. So the veterinarian is saying her entire tail should be removed to make sure the margins around the tumor are adequate to excise any cancer cells at the edges. While I can adjust to the reality of no tail, my concern centers on bleeding as well as on missing limb pain. Is there something different I should ask for? Remove the tumor but keep the tail? Add radiation to the tumor location to wipe out any stray cancer cells instead of taking off the tail? Forget all treatment, ignore the lump, and let the dog live out her life? What would you recommend?
Rochester, New York
Dear Ms. Gabryel,
A. Assuming a competent tail amputation is performed, there should be minimal trouble with bleeding. And there won’t be missing, or phantom, limb pain. Your dog will not keep feeling her tail once it’s gone.
As far as radiation, that wouldn’t be instead of amputation. Whether radiation is necessary would depend on if the vet feels he was in fact able to get adequate margins. If not, radiation will be recommended, even with the tail gone. “But my guess is that it won’t be needed,” says Tufts veterinary surgeon John Berg, DVM, much of whose work is excising cancerous tumors on the operating table. Excising the tail should get far enough all around the tumor to take care of things.
“What I would not do,” Dr. Berg says, “is ignore the lump.” That wouldn’t end well, whereas treating a mast cell tumor often has a happy ending. Granted, overall prognosis depends on the grade of the tumor, which is predictive of metastatic potential, that is, the potential for the cancer to spread. A cancer of low or intermediate grade has only about a 20 percent chance of spreading; high grade, well over 50 percent potential. But most tumors are low/intermediate,” Dr. Berg says, and removing them means the dog usually gets to live her normal life span.