Primary Hepatic Paraganglioma Mimicking Hepatocellular Carcinoma: A Diagnostic Challenge and Literature Review.

Primary hepatic paraganglioma (HPGL) is an exceptionally rare neuroendocrine tumor and represents a significant diagnostic challenge due to nonspecific clinical and radiological features. We report a rare case of primary HPGL initially misdiagnosed as a hypervascular liver tumor. A 72-year-old female was referred for evaluation of an incidentally detected hepatic mass. Preoperative assessment included contrast-enhanced computed tomography (CT), magnetic resonance imaging (MRI), and 18F-fluorodeoxyglucose positron emission tomography/CT (18F-FDG PET/CT). Surgical resection was performed, followed by histopathological and immunohistochemical examination. Postoperative functional imaging was used to exclude extrahepatic disease. Imaging revealed a 2.5-cm hypervascular lesion in segment IVb of the liver with moderate FDG uptake and no evidence of extrahepatic disease. The patient underwent open wedge resection, during which marked intraoperative blood pressure fluctuations were observed. Histopathology demonstrated a paraganglioma with characteristic organoid architecture and supportive immunohistochemical findings. Postoperative iodine-131 metaiodobenzylguanidine (MIBG) scintigraphy showed no additional lesions, confirming the diagnosis of primary HPGL. The postoperative course was uneventful, and no recurrence was detected at six-month follow-up. Primary HPGL is a rare entity that may mimic more common hypervascular hepatic tumors, leading to misdiagnosis. Surgical resection remains the treatment of choice. Intraoperative hemodynamic instability may serve as an important diagnostic clue, even in clinically nonfunctional cases. Long-term follow-up is recommended due to the uncertain malignant potential of these tumors.