Non-cirrhotic Portal Hypertension from Chemotherapy-induced Intrahepatic Non-tumorous Arterioportal Fistula

Abstract

Purpose: Intrahepatic arterioportal fistulas (APF) are rare, are mostly caused by trauma or malignancy, and can cause presinusoidal portal hypertension. We report a case of chemotherapy-induced non-tumoral intrahepatic APF (CI-APF) presenting with non-cirrhotic portal hypertension (NCPH). A 57-year-old white man presented with chronic abdominal pain and abnormal liver tests for one year (3/13). He underwent right hemicolectomy for cecal adenocarcinoma (2/12), and received adjuvant chemotherapy with FOLFOX (4/12-9/12). His laboratory data showed thrombocytopenia and fluctuating liver tests (AST 43-90 U/L; ALT 49-91U/L; alkaline phosphatase 173-280U/L, and total bilirubin 0.4-1.7mg/dL). Viral and autoimmune hepatitis were excluded. Physical exam was normal. Upper endoscopy showed new trace esophageal varices. Abdominal magnetic resonance imaging reported a large APF in both lobes of the liver, with hyperarterial vascularity perfusing the right hepatic lobe, early shunting to the portal vein, moderate atrophy of right lobe of the liver, distension of the portal vein, and splenomegaly with otherwise patent hepatic vasculature (A). Trans-jugular liver biopsy with wedge pressure and hepatic arteriography showed hepatic vein pressure gradient of 3 mmHg and hepatic arterial to portal vein shunting (B). Liver biopsy was notable for focal sinusoidal dilatation, unremarkable bile ducts, portal tracts, and hepatocytes, with no fibrosis. Prior imaging showed normal hepatic anatomy (2/2012, 6/2012) and fatty infiltration of the liver without vascular abnormalities (11/2012). The occurrence of APF with presinusoidal portal hypertension and the temporal relationship with chemotherapy led to the final diagnosis of NCPH from CI-APF. Several cases of NCPH in patients undergoing chemotherapy for metastatic colorectal cancer have been reported. It is believed that severe hepatic injury from chemotherapy results in benign transformation of the hepatic parenchyma into nodular regenerative hyperplasia (NRH). In our case, the presence of pre-sinusoidal portal hypertension is more supportive of obliterative portal venopathy leading to APF, rather than NRH. Shunt reduction with minimally invasive techniques such as transcatheter hepatic artery embolization have been successfully performed without severe complications.Figure