Poorly differentiated adenocarcinoma with signet ring cells of the gallbladder producing a high level of alpha-fetoprotein: A case report.

Abstract

Alpha-fetoprotein (AFP) can become elevated in hepatocellular carcinoma (HCC), yolk sac tumors and other malignant tumors of various organs. Herein, we present a case of AFP-producing gallbladder carcinoma with signet ring cells successfully treated with laparoscopic whole-layer cholecystectomy. A 69-year-old woman was found to have increased levels of the tumor marker AFP (16.1 to 1474ng/mL), and an irregularly shaped mass 22mm in size in the gallbladder at 5months follow-up after transcatheter arterial chemoembolization and radiofrequency ablation for HCC in segment 3 of the liver. As no additional metastases were detected, we diagnosed the patient with either AFP-producing gallbladder carcinoma (cT2aN0M0, cStage IIa, UICC 8th) or gallbladder metastasis from HCC. Laparoscopic whole-layer cholecystectomy was performed, and histological examination revealed AFP positive poorly differentiated adenocarcinoma with signet ring cells (pT2bN0cM0, pStage IIb, UICC 8th). AFP levels were remarkably decreased after operation (15ng/mL), and no residual tumors or distant metastases were observed on contrast enhanced computed tomography (CE-CT), indicating that the tumor was an AFP-producing gallbladder carcinoma rather than metastasis of HCC. Due to the similar developmental origin of the liver and gallbladder, gallbladder carcinoma could produce AFP in some cases. Considering that AFP is predominantly synthesized during embryogenesis, the status of cellular differentiation would be associated with the ability to synthesize AFP. When no lesions except for in the gallbladder can account for elevated AFP levels, clinicians should consider AFP-producing gallbladder carcinoma.