Carcinosarcoma of the stomach with alpha-fetoprotein-producing hepatoid adenocarcinoma: an unexpected combination of two rare subtypes of gastric cancer in one tumor

Abstract

Carcinosarcoma is a rare malignant neoplasm comprising both epithelial and mesenchymal components. Hepatoid adenocarcinoma (HAC) is another rare type of cancer. To date, there are only four reported cases of concurrent carcinosarcomas with HAC across all tumor types, all of which were observed in uterine tumors. Here, we report an unusual case of gastric carcinosarcoma associated with alpha-fetoprotein (AFP)-producing HAC in a 76-year-old woman. Upon admission, the patient had an elevated serum AFP concentration (448 µg/L), a necrotic polypoid tumor of the central gastric cardia revealed by endoscopy, and no evidence of distant metastasis indicated by computed tomography (CT). Owing to malignancy indicated by biopsy, the patient underwent proximal subtotal gastrectomy. The resected tumor was composed of both an HAC component and a sarcoma component, microscopically. The sample was positive for AFP, hepatocyte paraffin (Hep-Par) 1, glypican-3, SALL4, CDX2, cytokeratin (CK) (pan), CK18, desmin, and vimentin staining immunohistochemically. In summary, the tumor was diagnosed as carcinosarcoma of the stomach with AFP-producing HAC. To our knowledge, this is the first report of gastric carcinosarcoma with AFP-producing HAC in the English literature describing gastric tumors.

Integrative analysis reveals a clinicogenomic landscape associated with liver metastasis and poor prognosis in hepatoid adenocarcinoma of the stomach

“…From a clinicopathological perspective, most HAS patients exhibited a dramatic elevation in serum AFP level 54 , 55 , which was considered a remarkable feature contributing to aggressive behavior and poor prognosis 53 . Ye et al reported a marked elevation in serum AFP level in two HAS cases with lymph nodes and/or liver metastases (5845 ng/mL and > 50000 ng/mL, respectively) 56 .…”