small intestinal tumors


Small intestinal tumors are uncommon in cats and dogs. The majority of intestinal tumors are malignant and include lymphoma (especially cats), adenocarcinoma and leiomyosarcoma. The metastatic risk for malignant tumors is moderate with metastasis to the regional lymph nodes, liver and lungs relatively common.



Ultrasonography is recommended for both diagnosis and clinical staging. Other diagnostic tests include contrast radiographs (barium study) and endoscopy. A preoperative diagnosis is sometimes not possible and surgery may be required to both diagnose and treat gastric tumors.



An abdominal ultrasound is recommended to check for metastasis to the regional lymph nodes and liver. Chest radiographs or CT scans are done to check for metastasis to the lungs.



The majority of intestinal tumors are treated with surgical resection with wide margins (3-5 cm) and end-to-end anastomosis. Lymphoma can be treated with multiagent chemotherapy protocols, but surgery is still often required for definitive diagnosis. Chemotherapy, using a combination of cisplatin and 5-fluorouracil, has been described for dogs with intestinal adenocarcinoma.



The median survival time for cats with intestinal lymphoma treated with chemotherapy is 201-280 days. The prognosis is better for cats responding to chemotherapy with a median survival time greater than 11 months. The median survival time for cats with surgically excised intestinal adenocarcinoma is up to 15 months and this is not decreased by metastasis to the lymph nodes. The prognosis is very poor for cats with intestinal mast cell tumor because of widespread metastasis at the time of diagnosis. 


In dogs, the median survival times following intestinal resection and anastomosis is 16 days for mast cell tumor, 300 days for adenocarcinoma, and 21 months for leiomyosarcoma.


To be updated