Primary hepatic chronic expanding hematoma: a case report and literature review.

Chronic expanding hematoma (CEH), first reported in 1968, is a hematoma that gradually enlarges over a long course of time after an initial period of bleeding. It can occur anywhere in the body; however, there are many reports of its occurrence in the thoracic cavity. Primary hepatic CEH is extremely rare. In this current study, we report on a case of primary hepatic CEH diagnosed preoperatively, with a review of the literature. A 68-year-old man presented with liver dysfunction. Abdominal computed tomography revealed a giant cystic tumor in the left lobe of the liver, with a longer axis of approximately 12 cm. Magnetic resonance imaging revealed a mosaic pattern with a mixture of high and low signals within the tumor on T1-weighted images and a high signal at the tumor margin on T2-weighted images. Based on these findings, primary hepatic CEH was suspected. However, other malignant tumors could not be excluded owing to tumor compression resulting in bile duct dilatation. Left trisectionectomy was performed, followed by bile duct drainage and percutaneous transhepatic portal vein embolization. Intraoperative hemorrhage was controlled by the Pringle maneuver and with temporary clamping of the inferior vena cava. Pathological examination revealed a pseudocyst containing a clot, consistent with CEH. In conclusions, the case report illustrates the potential to enhance preoperative diagnosis, inform surgical approaches, and minimize associated risks. Furthermore, it highlights the importance of increasing awareness and research on this condition for improved clinical decision-making and patient care.