High-Grade Hepatic Spindle Cell Carcinoma as a Cause of Diffuse Right Hepatic Lobe Hypermetabolism Identified With 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (18F-FDG PET/CT) Imaging

We present a rare case of high-grade spindle cell liver carcinoma investigated using ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) in a 70-year-old man with worsened clinical symptoms for more than three months. These include hiccups, belching, loss of appetite, and significant weight loss of 30 kg over the last three months. ¹⁸F-FDG PET/CT was employed as part of the initial diagnostic assessment, revealing intense diffuse right hepatic lobe hypermetabolism. Fused PET/CT images revealed a locally confined right hepatic lobe tumor exhibiting heterogeneous metabolic activity with predominant hypermetabolism surrounding two internally contained hypometabolic islands. These findings suggested an aggressive and unusual neoplastic pattern. Ultrasound-guided biopsy confirmed high-grade spindle cell sarcoma of the liver. Unfortunately, the patient passed away shortly thereafter, precluding therapeutic decisions.