Abstract: Objective The aim of the present study was to retrospectively analysis the imaging manifestations and clinicopathological characteristics of sarcomatoid hepatocellular carcinoma (SHC) patients, in order to improve the efficiency of clinical diagnosis of SHC.Methods The clinical data of 11 patients with pathologically confirmed SHC from January 2012 to March 2021 were collected. The clinical symptoms, Computed tomography (CT) and magnetic resonance imaging (MRI) findings, pathological features, immunohistochemical staining, and other findings during followed-up were retrospectively analyzed.Results Among the 11 patients with SHC, 7 were male and 4 were female, of which 6 patients have single lesions, 5 patients have multiple lesions, and 1 patient was complicated with hepatocellular carcinoma and cholangiocellular carcinoma. One patient underwent CT enhanced scan, 5 patients underwent MRI enhanced scan, and 5 patients underwent CT and MRI enhanced scan. The imaging examination of the SHC lesions showed low-density on CT plain scan, circular or patchy uneven enhancement in the arterial phase of the enhanced scan, and low-intensity in the portal phase and the delayed phase; MR plain scan showed slightly longer T1 and longer T2 signals, and one case of intratumoral hemorrhage showed focal and shorter T1 signals, and the lesion enhancement method was similar to CT findings; Pseudocapsular enhancement was observed in 3 cases. Septal changes were seen in 1 case, with necrotic cystic areas within the tumor. One patient with mixed carcinoma showed delayed enhancement on enhanced scan. Immunohistochemical results showed that Vimentin was positive in 9 patients; Hepa was negative in 8 patients; CK19 was positive in 4 patients; CD34 was positive in 8 patients; Ki67 was positive in 6 patients (Ki67>75%); EMA was positive in 5 patients; SMA was positive in 3 patients. Three patients had metastasis before surgery and 5 patients had recurrence and metastasis after surgery.Conclusion The clinical features and imaging manifestations of SHC are atypical and rare. If a large intrahepatic tumor is found with large necrotic cystic areas within the tumor, ring-shaped, patch-like edge enhancement or uneven enhancement arterial phase lesions shown in enhanced scan, the possibility of SHC should be considered.

Key words: Sarcomatoid hepatocellular carcinoma, pathological features, magnetic resonance imaging, Computed tomography, immunohistochemical staining