The perianal region is the area of skin surrounding the exit of your dog's intestine. Canines are equipped with a number of glands in this region, including two larger bodies called anal sacs. Perianal gland carcinoma occurs in dogs of both genders, although it's more common in females.
Anal sac carcinoma describes cancerous growth when it occurs in one of the two sacs on either side of your dog's anus. These sacs store hormone-laden chemicals produced by smaller glands in the surrounding tissue. There are also many smaller glands on the surface of the skin in the perianal region. Growths in these glands are simply known as perianal tumors. Cancer in the anal sac glands account for less than 20 percent of perianal tumor cases in dogs but are most common in older females, according to Colorado State University Animal Cancer Center.
It's difficult to spot a perianal tumor on your pet early in its development, especially if he has long hair. As the malignant growth expands, it pushes against your dog's intestines and bulges out from the skin as a noticeable swelling. If he fusses over his rear end by licking or chewing at it constantly, he could be uncomfortable from an unnatural growth in the area. This is a warning sign of perianal gland carcinoma, so take him to the vet for a checkup. Other symptoms include constipation, lack of appetite and thin or ribbonlike stool, according to Pawspice.
Diagnosis and Health Risks
Your vet can't tell if a tumor is carcinoma or a benign growth until he takes a sample and examines further. Lab tests should reveal the nature of the tumor, which determines the method and level of treatment needed. Malignant tumors in the perianal glands can spread to nearby tissue or metastasize to the lymph nodes if left untreated, according to VCA Animal Hospitals. Cancer in the lymph nodes and endocrine system is a fatal ailment that quickly travels throughout the body. Prompt diagnosis and treatment can save your pet's life.
Surgery to cut out the tumor is the standard treatment for perianal gland carcinoma in dogs. It's not always successful at permanently treating the cancer, but it can prolong your dog's life even if malignant cells have spread elsewhere. Chemotherapy and radiation treatment sometimes manages tumors that are too big to remove. Combinations of surgery and other treatment methods can extend the patient's estimated survival time to over a year. Carcinoma can return even if the surgery successfully removed all of the malignant cells. Regular checkups are part of the post-op lifestyle.