Evaluation of Portal Vein Stenting in Patients With Portal Vein Stenosis and Gastrointestinal Cancers

Inclusion Criteria: * COHORT A: All patients will undergo initial staging and treatment as per the institution standard of care. Patients will be considered eligible for porto-mesenteric venous stenting (PVS) if: * There is \> 75% porto-mesenteric venous stenosis in either main portal vein (PV), left PV, right PV, or the superior mesenteric vein (SMV), even in absence of symptoms of portal hypertension * Patients presented with any degree of vascular narrowing of said vessels and symptomatic portal hypertension including variceal bleeding, refractory ascites, abdominal pain, intestinal edema, or diarrhea after exclusion of tumor-related causes as direct tumor invasion or peritoneal dissemination * COHORT B: Patients who have thrombosis/stenosis of the main portal vein but who did not undergo stenting