Gastrointestinal Tumours
Tumours of the stomach, small intestine, colon, and rectum.
What is Gastrointestinal Tumours?
GI tumours in dogs include adenocarcinoma, lymphoma, leiomyosarcoma, and gastrointestinal stromal tumours (GIST). Signs are often nonspecific and mimic chronic GI disease, so persistent GI signs in senior dogs warrant imaging.
Common signs and symptoms
Signs vary between dogs and can be subtle at first. Watch for the following, especially if several appear together or persist for more than a few days:
- Chronic vomiting or regurgitation
- Diarrhoea, sometimes with blood
- Weight loss despite normal appetite
- Straining to defecate (with rectal tumours)
- Signs of GI obstruction: vomiting food, abdominal pain
Risk factors
Certain dogs are more predisposed. Understanding risk helps you screen earlier and act sooner.
- German Shepherd (gastric carcinoma)
- Belgian Shepherds
- Senior dogs
When to see a vet
Use this as general triage guidance, not a substitute for veterinary advice.
- Book a routine appointment if: any GI signs in a senior dog lasting more than 2 weeks deserve bloodwork and abdominal imaging.
- Seek urgent care if: vomiting with an unproductive urge, obvious abdominal pain, or rectal bleeding.
Diagnosis and management
Diagnosis combines abdominal ultrasound, endoscopy with biopsy, and CT for staging. Treatment depends heavily on tumour type: surgery for focal masses, chemotherapy for lymphoma, tyrosine kinase inhibitors for GIST.