Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.

Stomach and Intestinal Cancer (Leiomyosarcoma) in Dogs

Leiomyosarcoma of Stomach, Small and Large intestine in Dogs

Leiomyosarcoma, a rare cancerous tumor, originates from the smooth muscles of the stomach and intestines in dogs. This condition poses significant danger and discomfort, particularly afflicting older dogs, typically over six years of age. Interestingly, all breeds are equally susceptible to leiomyosarcoma. Furthermore, this cancer tends to spread to various locations within the gastrointestinal tract and other organs in the body.


The symptoms and types of leiomyosarcoma primarily manifest in the gastrointestinal tract, presenting as:

  • Vomiting
  • Weight loss
  • Diarrhea
  • Presence of blood in stool (hematochezia)
  • Gas (flatulence)
  • Audible stomach growling or rumbling sounds (borborygmus)
  • Sensation of incomplete defecation (tenesmus)


The precise cause of this cancer remains unknown at present.


For diagnosis, your veterinarian will gather a comprehensive history of your dog’s health, including the onset and characteristics of the symptoms. A thorough physical examination will be conducted, along with tests such as a biochemistry profile, urinalysis, and complete blood count (CBC). While these tests typically yield results within normal ranges, advanced cases of the disease may exhibit abnormalities such as anemia, leukocytosis (an abnormally high number of white blood cells), and hypoglycemia (abnormally low glucose levels).

Additional diagnostic procedures include abdominal X-rays and ultrasounds to detect changes in the stomach and intestinal walls, such as thickening. Contrast radiography is employed to enhance tissue visualization and pinpoint the tumor’s location. Endoscopy serves as a valuable tool for direct visualization of affected areas. During this procedure, an endoscope—a flexible or rigid tube—is inserted into the esophagus down to the stomach and intestines. The veterinarian visually examines the region and obtains a biopsy sample from the affected area (stomach and/or intestine) to confirm the diagnosis.


The primary treatment option is surgery, which entails the removal of the tumor mass along with surrounding normal tissue. However, the prognosis heavily relies on the extent of metastasis, particularly in organs like the liver.

Living and Management

In cases where metastasis has spread to other body organs, the prognosis is notably grim, with survival typically lasting only a few months. Surgery might enhance survival rates in certain cases, necessitating the complete removal of the tumor mass. After surgery, regular checkups, X-rays, and abdominal ultrasounds every three months are essential. Some dogs may require specialized easily digestible diets and pain medication to alleviate discomfort. It’s crucial to diligently follow the veterinarian’s instructions and monitor the dog for signs of vomiting, diarrhea, abdominal distention, and abdominal pain, which could indicate tumor recurrence.

Scroll to Top