Stenting of the Superior Mesenteric Vein in Midgut Carcinoid Disease with Large Mesenteric Masses

Midgut carcinoid (MGC) tumors generally develop in the small intestine and in > 50% of cases also present with lymph node metastases in the mesentery. The majority of these tumors are surgically resectable, but a fraction are inoperable and may cause obstruction of the superior mesenteric vein (SMV), often associated with stasis of the intestinal wall and severe symptoms. These symptoms include severe abdominal pain, attacks of diarrhea, and malnutrition. Seven patients with severe MGC including a large fibrotic inoperable mesenteric mass and severe symptoms were studied. After an obstructed SMV and signs of venous stasis in the small intestine were demonstrated, an expandable stent was inserted after puncturing an intrahepatic portal venous branch. The associated venography, patient symptoms, and radiological signs on computed tomography (CT) scans were evaluated. Four patients demonstrated resolution of their symptoms. In one patient who had intra-abdominal lymph leakage/chyloperitoneum, a complete normalization of the circulation followed and the intra-abdominal lymph leakage stalled. The venographies demonstrated normalization of the venous blood flow through the SMV, and CT scans demonstrated reduction in the thickness of the intestinal wall. In two cases there were no changes in the symptoms, and in one case a slight worsening of the symptoms ensued. In general, reductions of symptoms were associated with the degree of normalization of venous blood flow. We conclude that in selected patients with MGC stenting of the SMV may improve symptoms.