Distinctive imaging features of liver metastasis from gastric adenocarcinoma with enteroblastic differentiation: A case report.

Background: Gastric adenocarcinoma with enteroblastic differentiation (GAED) is one of the common subtypes of alpha-foetoprotein (AFP)-producing gastric cancer. GAED frequently results in venous invasion and liver metastasis, the latter being particularly linked to a poor prognosis. So far, the evidence for liver metastases from AFP-producing gastric cancer is only focused on those from gastric hepatoid adenocarcinoma, owing to their imaging similarities with hepatocellular carcinoma. This case report describes the characteristic diagnostic imaging findings of liver metastasis from GAED.

Case summary: A 65-year-old man who had undergone a pyloric gastrectomy for GAED two years ago was found to have a liver tumor in the hepatic segment 7, accompanied by elevated serum AFP levels. Dynamic contrast-enhanced computed tomography revealed the tumor showing peripheral-dominant enhancement in the arterial phase with persistent central enhancement in the delayed phase. Gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid-enhanced magnetic resonance imaging demonstrated a signal drop in the tumor periphery in chemical shift imaging, along with arterial enhancement. Additionally, rim-like hypointensity surrounding the tumor was observed in the hepatobiliary phase. Postresection examination confirmed the tumor to be a metastasis from GAED. Histopathological examination revealed severe invasion of the tumor into the portal vein and hepatic vein surrounding the tumor, which explained the imaging features.

Conclusion: The imaging features of blood flow alternations resulting from vascular invasion may be crucial to diagnosing liver metastases from GAED.