[From Tufts April 2010 Issue]
My dog, a 10-year-old shepherd-husky mix, went for her routine checkup today, and I mentioned that she has been licking her bottom quite a bit. The vet said her right anal gland was blocked and expressed it. Molly growled and lunged, which she did once five months earlier on a visit.
The vet felt two hard masses while expressing the gland. She said they are tumors, and their location is not amenable to surgery. As we spoke, I realized the signs I’d been seeing all along added up—increased thirst and urination, flattened ribbon-like feces, occasional difficulty defecating, the continual licking of her bottom, smelly breath.
Although the vet would refer me to a veterinary specialist, she reiterated that the location makes the tumor non-resectable. She wouldn’t put a label on the cancer, but from what I read, it seems like it’s anal sac cancer. She also suspects that our last visit, when Molly acted out of character, may have been a result of the cancer. What can I expect? Is this a fast-growing cancer? Will I have much time with her? I love her very much.
I am very sorry to hear about Molly. I would agree with your veterinarian that a mass in the anal area in an older dog could be malignant, and if the mass is large enough to compress the anus or rectum, causing ribbon-like feces, that increases the likelihood that it is malignant.
However, many malignant tumors in this area, including large ones, can be surgically excised. I would strongly recommend that you see a surgical specialist about the possibility of removal. You are right that one of the rule-outs is an anal sac carcinoma, but that is not the only possibility. Other malignancies can occur in the area.
Even though anal sac carcinomas have a strong tendency to spread to distant sites, such as the lymph nodes in the abdomen, dogs that undergo surgical removal often have well over a year of good quality time after surgery. And some of the other tumors that can occur in the area can have an even better prognosis. Be prepared that, depending on the type of tumor, either chemotherapy or radiation therapy may be part of the recommendation. You can select a treatment based on your financial situation and your personal feelings about what is right for Molly, but seeking a surgical opinion is a critical first step
John Berg, DVM, ACVS
Chair, Department of