Biliary Adenofibroma and the Threat of Malignant Transformation

Biliary adenofibroma (BAF) is a rare hepatic tumor with a high risk for malignant transformation. Since BAF shares many characteristics with other hepatic lesions, diagnosis usually requires meticulous evaluation. The literature review revealed 29 reported patients of BAF, with malignant transformation occurring in 45% of patients. High Ki-67 (>40%) and mutated/overexpressed p53 staining were associated with malignancy, but some patients also had malignant features with low Ki-67 (≤10%) and wild-type p53. We report an elderly female patient who was initially diagnosed with benign liver hemangioma based on an abdominal ultrasound. The mass enlarged by 4 cm raising concerns about potential complications, including hemorrhage, which led to hepatic segmental resection. Histopathological examination revealed predominantly BAF features with focal areas that showed malignant cholangiocarcinoma characteristics.