Hepatoid Adenocarcinoma of the Stomach: A Challenging Diagnostic and Therapeutic Disease through a Case Report and Review of the Literature

Abstract

Hepatoid adenocarcinoma of the stomach (HAS) is a rare aggressive tumor with hepatocellular differentiation. HAS often produces alpha fetoprotein (AFP) and metastasizes to the lymph nodes and the liver. Molecular studies revealed Her2 amplification and overexpression, association with p53 mutations, but no association with KRAS mutations. EGFR and BRAF mutations have not yet been evaluated in hepatoid carcinoma of the stomach so far. Hereby, we present a case of a 41-year-old female patient with HAS with high AFP level and liver metastases. Molecular analysis revealed Her2 overexpression by immunohistochemistry (IHC), but no EGFR, KRAS, or BRAF mutations were detected. The patient underwent chemotherapy type DCX (docetaxel, cisplatinum, and capecitabine) every 3 weeks with partial response after two cycles, maintained for eight cycles, and then was on maintenance therapy with trastuzumab for 7 months before relapsing and dying 18 months from the day of diagnosis. Conclusively, HAS may be misdiagnosed as hepatocellular carcinoma; therefore, it should be considered in the differential diagnosis of multiple hepatic nodules with high AFP and no history of hepatitis, liver fibrosis or cirrhosis.

The prognosis of hepatoid adenocarcinoma of the stomach: a propensity score-based analysis

“…The gastroscopy biopsy and (or) surgical specimens of HAS both have different percentages of HAS cell components. Once the pre-operative and postoperative specimens were found with adenocarcinoma, hepatocellular carcinoma or the sole hepatocyte-like regions in morphology, which would be added to examine several immune-histochemical markers, such as AFP [19], Glypican-3(GPC-3), SALL4 and Hap-Par 1 [7,20]. If the immunohistochemical marker AFP was positive, we preliminarily considered the diagnosis of a patient's disease as HAS.…”

“…The gastroscopy biopsy and (or) surgical specimens of HAS had different HAS cell component percentages [7]. Therefore, the definitive diagnosis of HAS depended on the histomorphological features plus immunophenotypical evidence [19].…”

The prognosis of hepatoid adenocarcinoma of the stomach: a propensity score-based analysis

“…The gastroscopy biopsy and (or) surgical specimens of HAS both have different percentages of HAS cell components. Once the pre-operative and postoperative specimens were found with adenocarcinoma, hepatocellular carcinoma or the sole hepatocyte-like regions in morphology, which would be added to examine several immune-histochemical markers, such as AFP [21], Glypican-3(GPC-3), SALL4 and Hap-Par 1 [7,22]. If the immunohistochemical marker AFP was positive, we preliminarily considered the diagnosis of a patient's disease as HAS.…”

“…The gastroscopy biopsy and (or) surgical specimens of HAS had different HAS cell component percentages [7]. Therefore, the de nitive diagnosis of HAS depended on the histomorphological features plus immunophenotypical evidence [21].…”

<p>Therapeutic Approaches to Gastric Hepatoid Adenocarcinoma: Current Perspectives</p>

“…Due to its rarity, a timely and proper identification and a correct diagnosis may be delayed and sometimes challenging 7,12,13. This may further jeopardize the prognosis of these patients.…”