Abernethy malformation and hepatocellular carcinoma: a serious consequence of a rare disease.

Congenital portosystemic shunts (CPSS) are a rare vascular consequence of embryogenetic vascular alterations or the persistence of the fetal circulation elements, first described by John Abernethy in 1793 and classified by Morgan and Superina, into complete and partial portosystemic shunts. Its prevalence to this day has not been defined. We present a patient series of a 44-year-old and 47-year-old man and woman, with this rare congenital malformation and underlining hepatocellular carcinoma (HCC) treatment strategies. Over half of the individuals with CPSS have benign or malignant liver tumours, ranging from nodular regenerative hyperplasia, focal nodular hyperplasia, adenomas, HCC and hepatoblastomas. Additionally, it is known that half of individuals with Abernethy malformation type Ib will develop one or multiple types of tumours. There seems to be a direct association with tumorigenesis and CPSS, which is the primary consequence of absent portal flow. Surgery is the treatment of choice, either as a curative resection or orthotopic liver transplantation if recommended as per the criteria, in which replacing the hepatic parenchyma in the setting of an Abernathy malformation will correct the underlining hyper-arterialisation. © BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.