Rapidly Progressing Sarcomatoid Hepatocellular Carcinoma after Needle Biopsy and Radiofrequency Ablation.

BACKGROUND Sarcomatoid hepatocellular carcinoma is a rare, primary malignant liver cancer. Its pathogenesis is unknown, but it often occurs in patients who have undergone repeated antitumor therapies for hepatocellular carcinoma. Sarcomatoid hepatocellular carcinoma is more likely to recur and has a worse prognosis than that of hepatocellular carcinoma. As no specific features have been identified in the symptoms, serological findings, or imaging findings, it is difficult to accurately diagnose the disease before surgical resection or autopsy. CASE REPORT An 83-year-old woman was diagnosed with hepatocellular carcinoma 20 years ago. Radiofrequency ablation was initially performed. Thereafter, invasive, non-surgical treatments were repeated. The most recent treatment was 4 years ago, during which computed tomography suggested recurrent hepatocellular carcinoma. However, upon needle biopsy, histological examination revealed spindle-shaped tumor cells and actively mitotic cells. Immunohistochemical analysis showed negative results for Arginase-1, HepPar1, and Glypican3 and positive results for AE1/AE3, CK7, and vimentin. Therefore, sarcomatoid hepatocellular carcinoma was diagnosed, which was treated with radiofrequency ablation but progressed rapidly thereafter. Considering the rapid disease progression, the patient was treated conservatively. However, the patient's general condition gradually deteriorated, resulting in death. CONCLUSIONS Compared with hepatocellular carcinoma, sarcomatoid hepatocellular carcinoma is more prone to recurrence and has a poorer prognosis. Therefore, aggressive surgical resection seems to be the most appropriate treatment for sarcomatoid hepatocellular carcinoma at present. Additional hepatic resection or follow-up imaging in a short period should be considered at the time of diagnosis of sarcomatoid hepatocellular carcinoma by biopsy, considering the risk of seeding or recurrence.