Benign Tumours and Pseudotumours Within the Porta Hepatis Masquerading as Perihilar Cholangiocarcinoma

Hilar cholangiocarcinoma (HC), also referred to as Altemeier-Klatskins tumour, is a lethal primary extrahepatic carcinoma of biliary epithelial origin, arising within 2cm of the hilar confluence. Radical surgical excision provides the best chance for a cure; however, the management of patients with HC is challenging not only because of the need for a high level of skill in biliary and hepatic resections, but also because of the difficulty in reaching an accurate diagnosis preoperatively. In fact, the differential diagnosis of HC is a diagnostic dilemma which is currently persisting, as modern, sophisticated diagnostic modalities are not always able to provide a definitive preoperative diagnosis. This difficulty is compounded by the fact that alternative entities that mimic HC may be present in up to 25% of patients with hilar obstruction. This makes precise preoperative characterisation of a hilar stricture extremely important by preventing unnecessary, high-risk, major surgical procedures. Therefore, alternative benign entities masquerading as Altemeier-Klatskins tumour deserve an important place in the differential diagnosis of hilar obstruction.

Considering the important clinical implications that a precise diagnosis of the aetiological cause of a biliary obstruction at the liver hilum would have, this paper will focus on the differentiation between HC and benign hilar obstructions and will review benign tumours and pseudotumours masquerading as HC along with their specific diagnostic features.