Gastrointestinal neoplasm (cancer) in cats and dogs is very rare and contributes to less than 1% of all cancers in pets. Although no specific causes for gastrointestinal tumors have been identified, the feline leukemia virus is believed to lead to gastrointestinal lymphoma in cats. Lymphoma is cancer of the lymph tissues, and was earlier considered to be the most common tumor of the GI tract in cats. Recent reports reveal that adenocarcinoma, malignant neoplasm of the glandular epithelium, may be the most common gastrointestinal tumor in cats.
Colonic lymphomas mostly attack older cats, and are large and diffusely swollen with a surface whose plane sections are all ellipses and circles. Lymphomas usually invade all layers of the colon, and ulceration and metastasis to layers of peritoneum attached to the back wall of the abdominal cavity are common.
Gastric leiomyomas appear round and smooth, and are covered with mucosa at the lesser curvature of the opening of the stomach. These are benign tumors, but may be ulcerated. Leiomyosarcomas, on the other hand, are malignant tumors of smooth muscle of the digestive tract, which may also attack the uterus, bladder or prostate.
Clinical signs of GI tumors vary and depend upon the location, extent of metastasis and the metabolic effects of the neoplasm, like abnormally high levels of calcium. Other symptoms include those normally associated with cancer, including vomiting, diarrhea (often with blood), weight loss, inability to control bowel movements, pain, and accumulation of fluid in the peritoneum.
History and physical examination are enough to suspect the presence of gastric and colon tumors in most cases. Confirmed diagnosis can be done with histological evaluation only. A number of tissue samples may be obtained at the time of laparotomy or during examination with an endoscope. Complete blood and urine profiles are performed to understand the extent of the concurrent diseases.
Surgical resection is preferred for treating gastric tumors, and care is taken to allow a margin of 4-8 cm so as to be sure that the entire tumor has been removed. Chances of recovery are excellent for benign tumors like leiomyomas, but despite surgery, the prognosis for malignant colon tumors is poor like it is in other metastatic cat cancers. Follow-up home care with cat cancer remedies and proper dietary support is integral to surgical treatment of all types of GI cancers.