Solitary AFP- and PIVKA-II-producing hepatoid gastric cancer with giant lymph node metastasis.

A 61-year-old man was admitted to our hospital because of abdominal pain and an abdominal mass. The patient had anemia and elevated serum alpha-fetoprotein (AFP) (9630ng/mL) and PIVKA-II (91mAU/mL) levels. Roentgenographic examination revealed an extra-gastric tumor in the upper abdomen, and gastroscopy revealed Bormann type 2 gastric cancer in the lower portion of the stomach. The preoperative diagnosis was synchronous gastric cancer and hepatocellular carcinoma (HCC), and surgery was performed. The extra-gastric tumor appeared to be an extra-hepatically growing HCC because the tumor was fed by vessels ramifying from the umbilical portion of the liver. Distal gastrectomy with resection of the extra-gastric tumor was performed, and histological examination of the resected specimen revealed that the gastric cancer was an AFP-producing hepatoid gastric adenocarcinoma and that the extra-gastric tumor was a lymph node metastasis. AFP-producing hepatoid gastric adenocarcinoma tends to metastasize to the regional lymph nodes and form a giant tumor. A giant tumor in the upper abdomen associated with gastric cancer may therefore be a clinical manifestation of AFP-producing hepatoid gastric adenocarcinoma.