Multiple hepatoid gastric adenocarcinoma: A case report and literature review

Abstract

Background Hepatoid gastric adenocarcinoma (HGAC) is a rare gastric malignancy that exhibits the characteristics of differentiated hepatocellular carcinoma and gastric adenocarcinoma. Most cases of HGAC are also accompanied by an elevated serum alpha-fetoprotein (AFP) concentration. Here, we report a rare case of HGAC involving two primary lesions.Case presentation A 61-year-old man presented at our institution with the complaint of upper abdominal pain. An examination revealed a significantly elevated serum AFP concentration. Abdominal computed tomography revealed a gastric tumour with enlarged peripheral lymph nodes and a cavernous haemangioma in the right anterior hepatic lobe. The patient underwent distal gastrectomy, and postoperative histopathology revealed two hepatoid gastric adenocarcinomas. Immunohistochemically, the tumours were positive for AFP, hepatocyte and chromogranin A (CgA), with a Ki67 index >90%. Following a postoperative diagnosis of HGAC, the patient was treated with a chemotherapy regimen of oxaliplatin combined with capecitabine. At the 6-month follow-up, the patient’s serum AFP concentration returned to the normal level. No signs of recurrence were detected.Conclusions Compared with other gastric cancers, HGAC tends to be more malignant and invasive, with a poor prognosis. These tumours are also prone to liver metastasis,but for which without liver metastasis may have a better prognosis. We hope that our experience with this extremely rare case of HGAC involving two different primary lesions without liver metastasis, as well as our literature review and summary of the etiological mechanism, pathological features, treatment and prognosis, will help improve the diagnosis and treatment of HGAC.