Alpha-Fetoprotein (AFP)-Negative Hepatoid Adenocarcinoma of the Stomach and its Associated Uncommon Features With a Review

Abstract

Hepatoid adenocarcinoma of the stomach is a rare histologic subtype of gastric carcinoma. Morphologically, it shows hepatocyte-like features and the tumor cells can show the expression of alpha-fetoprotein (AFP) in the tumor cells as well as in serum. There are a few AFP-negative hepatoid adenocarcinoma tumors that have been reported in the literature. A 45-year-old male patient presented with abdominal pain. Endoscopy and radiological studies showed an ulceronodular thickening in the antropyloric thickening with lymphadenopathy. He underwent radical subtotal gastrectomy with lymph node dissection. Microscopic examination showed adenocarcinoma with hepatocytic morphology, the presence of lymphovascular and perineural invasion, prominent peritumoral lymphocytic infiltration, multiple metastatic tumor deposit involving regional lymoh nodes and omentum. Adjacent gastric mucosa showed Helicobacter pylori-associated chronic atrophic gastritis with intestinal metaplasia. On immunohistochemistry (IHC), tumor cells were immunopositive for keratin 7, CDX2, and HepPar-1, p53 (focal), and MUC5AC (focal) while immunonegative for AFP, SALL4, MUC2, CD10, and HER2 (ERBB2) was negative. We report this AFP-negative hepatoid adenocarcinoma with its associated uncommon features and discussed the literature review and diagnostic approach.

Liver metastasis from hepatoid adenocarcinoma of the stomach: a case report and literature review

“…Subsequently, Ishikura ( 5 ) reported an instance of primary GA characterized by markedly elevated AFP levels (12,000 ng/ml), coining the term HAS. Subsequent investigations established that HAS may also manifest without elevated AFP levels ( 6 ), suggesting that elevated serum AFP serves as a hallmark of HAS but lacks absolute specificity. HAS is distinguished by its aggressive behavior and dismal prognosis in comparison to GA and HCC ( 3 , 7 – 9 ), with median survival ranging from 10 months to 18 months ( 10 , 11 ).…”

Immunohistochemical characteristics and potential therapeutic regimens of hepatoid adenocarcinoma of the stomach: a study of 139 cases

“…They also concluded that IHC and serum AFP levels are important to the diagnosis of HAS. There are already several studies regarding how serum AFP can improve the accuracy of diagnosis [ 8 , 9 ]. However, due to the rarity of HAS, the IHC and Epstein–Barr virus‐encoded small RNA (EBER) features of HAS have not been fully acknowledged [ 9 , 10 ].…”

“…There are already several studies regarding how serum AFP can improve the accuracy of diagnosis [ 8 , 9 ]. However, due to the rarity of HAS, the IHC and Epstein–Barr virus‐encoded small RNA (EBER) features of HAS have not been fully acknowledged [ 9 , 10 ]. According to previous research, HAS presents distinctive traits such as negativity for EBER, predominance of microsatellite stability (MSS), and high human epidermal growth factor receptor 2 (HER2) positive rate [ 11 , 12 ].…”