Canine Leiomyoma

The good news is canine leiomyoma is benign.
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Canine leiomyoma is a benign non-spreading tumor that grows from smooth muscle, most commonly in the intestinal tract and stomach. Occasionally, leiomyoma can also develop in the uterus or vagina of female dogs. The exact cause of these benign growths is unknown. While there's no particular breed or gender predisposition, leiomyoma typically occurs in middle-aged to older dogs, usually who are over 6 years old, according to PetMD.


In some cases of canine leiomyoma, the tumor can cause blockages in the dog's digestive tract or displace organs, resulting in secondary health problems. Symptoms depend on the exact location of the tumor. If the tumor is located in your dog's stomach or small intestine, symptoms can include vomiting, weight loss, a frequently growling stomach and flatulence. If you gently feel your dog's abdomen, you might be able to detect an unusual mass. If the tumor is located in his rectum or large intestine, symptoms can include weight loss, flatulence, unusual noise from the lower gastrointestinal tract, difficulty defecating, weakness caused by hypoglycemia and bloody stools. Leiomyoma in the reproductive organs rarely develops symptoms; it's typically discovered by accident during routine check-ups.


If your pooch displays any symptoms of canine leiomyoma, take him to your vet for a complete physical examination. He'll conduct a series of tests to rule out other health problems that can cause similar symptoms, such as cancer, a foreign body in the gastronomical tract, inflammatory bowel disease, pancreatitis and a parasitic infection. A complete blood count will be performed, as well as a urinalysis and biochemical profile. However, because leiomyoma growths are benign, routine tests often fail to detect their presence. X-rays and an abdominal ultrasound can be more helpful in revealing a mass or thickening in stomach walls and small intestinal tract. For a suspected tumor in the large intestine and rectum, radiography is also used to search for growths in those organs.


Removal of the leiomyoma through surgery is the usual treatment. In the majority of cases, surgery is completely successful, unless the dog is older and underlying health conditions cause complications. Because leiomyomas are benign, even large ones are usually successfully removed. In some instances, your vet might recommend trying to eliminate or manipulate a small tumor through dietary means rather than having the dog go under the knife, especially if he's older or in poor health. Dietary attempts to manipulate or reduce the tumor might include feeding the dog infrequent small meals that are easy to digest.

Home Care

Prognosis depends on the tumor's location, size and if the entire growth was successfully removed during surgery. If your doctor was able to completely remove the tumor, no additional procedures are usually required. He might give you specific postoperative instructions for home care during the recovery period, including possible dietary recommendations while your dog is healing. He may also want to monitor your pup's blood glucose levels after surgery, particularly if the leiomyoma caused him to become hypoglycemic. If your pooch shows any recurrence of his original symptoms prior to surgery, immediately contact your vet.