+ Biologic Behavior
- Intestinal LSA is the most common intestinal tumor
- Majority are multifocal and involve the small intestine
CLINICAL FEATURES
+ Clinical Signs
- Anorexia
- Weight loss
- Intermittent vomiting
- Diarrhea
- Severe, persistent vomiting is occasionally observed if proximal small intestinal tumor causes obstruction
Diagnosis
+ Physical Examination
- Palpable abdominal mass and cachexia are common
- Other findings include dehydration and abdominal pain
+ Laboratory Tests
- Mesenchymal tumors are associated with microcytic hypochromic anemia, hypoproteinemia, and mild leukocytosis
+ Abdominal Radiographs
- Abdominal mass, obstruction, or persistent irregularity of bowel appearance are identified in 25% of small intestinal tumors and nearly 50% of non-lymphoid intestinal tumors
- Abdominal mass is detected in 60% of canine mesenchymal small intestinal tumors
+ Contrast Radiography
Contrast Radiographs: Mural lesions include luminal filling defect, intestinal wall thickening, mucosal ulceration, abnormal positioning of intestinal loops, and constricting annular lesions
+ Ultrasonography
- Intestinal mass identified in 87% (13/15) dogs with non-lymphoid small intestinal tumors
- Loss of wall layering is an excellent predictive factor for differentiating intestinal neoplasia from enteritis in dogs (99% v 12%) with intestinal tumors 50.9-times more likely to have loss of wall layering
- Intestinal tumors also have significant increases intestinal wall thickness (15 mm v 6 mm) and are significantly less likely to have diffuse intestinal involvement (2% v 72%)
+ Exploratory Celiotomy
Definitive diagnosis with exploratory celiotomy and biopsy
TREATMENT
+ Surgery
- Debilitation and hypoproteinemia may complicate treatment
- Exploratory celiotomy with resection and end-to-end anastomosis with 4-8 cm margins and serosal patching
- Mesenteric and regional lymph nodes should be assessed ± aspirated
+ Chemotherapy
Multiagent protocols recommended for LSA as either adjuvant therapy or sole treatment for diffuse disease