Canine anal gland tumors in and around the anus (perianal tumors) can be divided into two categories, perianal gland tumors and anal sac tumors. Rectal tumors are also common in dogs.
- Perianal Gland Adenoma: Perianal glands are found anywhere around the anus, at the base of the tail and surrounding the male genitalia. Perianal gland tumors are often benign and occur frequently in male, intact dogs. However, female dogs can be affected, although Cushing’s disease should also be ruled out. These tumors are dependent on testosterone and in many cases will often disappear after castration. Multiple tumors can be present. In less than 5 percent of the cases, perianal gland tumors are malignant (fast growing) - these tumors can grow fast. Cancerous cells can spread later in the growth process (call metastasis).
- Anal Sac Adenocarcinoma: Anal gland tumors (Adenocarcinomas) are usually seen in older female dogs. An anal tumor is very dangerous and can spread quickly to the lymph nodes. This type of cancer creates a secretion that increases calcium in the blood and can damage the kidneys.
- Rectal Tumors: Rectal tumors are more common in dogs. They occur in older animals and consist of adenomas, adenocarcinomas, and leiomyomas.
Breeds at Higher Risk
- English Cocker Spaniel
- Alaskan Malamute
- German Shepherd
- English Springer Spaniel
- Cairn Terrier
- Mixed Breed
- Basset Hound
The first sign of this disease is a lump near the anal glands. The area may be red in color. Your veterinarian will do an ultrasound, blood tests and a test of the urine.
Anal gland tumors are often multiple, non painful, relatively solid masses that grow slowly.
The most common treatment for anal gland tumors is surgery for removal of the tumor. In some cases surgery is followed by radiation and chemotherapy to ensure that the entire area is treated. Antibiotics are used to avoid any post operative infection.
If you would like to try homeopathic (herbal) approaches to treatment a good commercial source to explore is PetAlive Formula for Prevention and Treatment of Cancer in Dogs. Herbal remedies are considered to be a supportive treatment vs. a cure in that they help to improve the overall health of the patient, while prescription medications focus on the specific area being treated. This is why herbal and prescription approaches are often used together. Do not use if a dog is undergoing chemotherapy without first consulting a veterinarian.
Prognosis of Dog Anal Gland Tumors
The prognosis of benign (non-cancerous) anal gland tumors is excellent either after castration or after local resection (removal).
The prognosis for malignant (cancerous) anal gland tumors is guarded. One study reports median survival for dogs with anal sac adenocarcinomas was 544 days, and dogs with tumors < 10 cm having a significantly better prognosis. Also, dogs with hypercalcemia and visible metastases fared significantly worse.
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