Primary Small Cell Carcinoma of the Liver Presenting With Acute Liver Failure

Primary small cell carcinoma of the liver is an exceptionally rare malignancy and must be distinguished from metastatic pulmonary small cell carcinoma by excluding a pulmonary primary. We report a 55-year-old man with suspected alcohol-related cirrhosis and diabetes who presented for elective lithotripsy and was found to have jaundice, hepatomegaly, and acute liver dysfunction. Laboratory evaluation demonstrated marked hyperbilirubinemia and transaminitis with normal alpha-fetoprotein. Imaging revealed interval hepatomegaly with diffuse hepatic involvement compared to CT performed three months earlier, which had shown no focal lesions. Liver biopsy demonstrated small cell carcinoma with immunohistochemical positivity for CD56 and synaptophysin and negative TTF-1 staining. Chest radiograph showed no evidence of pulmonary malignancy, supporting a primary hepatic origin. The patient developed progressive liver failure, hypoxic respiratory failure, and shock and died seven days after admission. A review of 31 previously reported cases demonstrates a predominance in middle-aged males, frequent association with cirrhosis or diabetes, common presentation with abdominal pain and jaundice, and typically normal tumor markers. These findings were consistent with those observed in our patient. Reported survivors most often received combined surgical resection and platinum-based chemotherapy. This case highlights the rare yet aggressive course of primary small cell carcinoma of the liver and its potential to cause rapid liver failure.