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

This study collects information about the safety and effect of portal vein stenting in gastrointestinal cancer patients with portal vein stenosis. This study may help researchers learn how long the portal vein stays open and free from blockage and the effects of portal vein stenting on patients' overall well-being.

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