A 68-Year-Old Man With Neutrophil-Rich Hepatoid Adenocarcinoma of the Gallbladder

BACKGROUND Neutrophil-rich hepatoid adenocarcinoma is an aggressive, rare variant of hepatoid adenocarcinoma, an extrahepatic malignancy with histological features resembling hepatocellular carcinoma (HCC). This report describes the case of a 68-year-old man with neutrophil-rich hepatoid adenocarcinoma of the gallbladder. CASE REPORT We present a case of hepatoid adenocarcinoma (HAC) of the gallbladder with prominent neutrophilic infiltration in a 68-year-old man who presented with dull right upper abdominal pain and jaundice. At the local hospital, computed tomography (CT) findings were suspicious for a malignant gallbladder tumor, and histological examination of the biopsy confirmed the diagnosis. Suspected multiple intra-abdominal metastases were also revealed by enhanced CT scan at our hospital. In accordance with the patient's wishes and after comprehensive discussion of the potential risks and benefits, a cholecystectomy with excision of a portion of the liver was performed. Multiple intra-abdominal nodules were also resected. The diagnosis of HAC and intra-abdominal metastases was rendered after histopathologic examination. Histologically, some tumor cells of the gallbladder showed features of hepatoid differentiation. Immunohistochemically, these hepatoid tumor cells expressed hepatocyte paraffin 1(HepPar-1), confirming the diagnosis of HAC. The histological findings of the intra-abdominal nodules were identical to those of the gallbladder tumor, confirming it as metastases. In addition, there was notable neutrophilic inflammatory cell infiltration in both the primary tumor and metastasis, suggesting that the tumor cells can recruit these inflammatory cells within the tumor. CONCLUSIONS This report highlights the aggressive behavior of extrahepatic neutrophil-rich hepatoid adenocarcinoma and the importance of histopathology in confirming the diagnosis.