A Unique Case of Alpha-Fetoprotein-Producing Esophageal Adenocarcinoma

Abstract

Alpha-fetoprotein (AFP)-producing esophageal adenocarcinoma (EAC) is a rare occurrence. Elevation of serum AFP is commonly associated with hepatocellular carcinoma and yolk sac tumors, but has also been reported in patients with other malignancies, most notably of gastrointestinal origin. However, the organs of origin typically include gastric, pancreatic, and biliary, but rarely esophageal. Here, we report a case of an AFP-producing EAC. A 51 year-old previously healthy man presented with new onset severe acid reflux and a weight loss of 35 pounds over a 2 week duration. He also endorsed 2 days of non-bloody emesis, but denied dysphagia or regurgitation of undigested food. Physical exam was only remarkable for right upper quadrant tenderness. The patient was slightly anemic with a hemoglobin of 12.8 g/dL. Elevated labs included: AST 66 U/L, ALT 81 U/L, CEA 6.4 ug/L, CA 19-9 317443 U/mL, and AFP 2524 ng/mL. Hepatitis B surface antigen and hepatitis C antibody were non-reactive. Computed tomography (CT) scan of the abdomen revealed abnormal thickening of the esophagus and multiple masses throughout the liver consistent with metastatic disease. CT-guided biopsy of one of the masses revealed CDX-2 positive adenocarcinoma, suggesting gastrointestinal origin. Subsequent upper endoscopy revealed a large, partially-obstructing mass in the lower third of the esophagus, the assumed primary source. Biopsy of the mass revealed ulcerated glandular mucosa with high grade dysplasia, with likely underlying malignancy. One month later, the patient underwent palliative esophageal stent placement. He was scheduled to begin FOLFOX/Herceptin therapy, but expired a week later. EAC is typically found in the lower third of the esophagus, and is associated with Barrett's esophagus, smoking, obesity, and epidermal growth factor polymorphisms. A previous study attempting to determine possible tumor markers in patients with esophagus cancer reported serum AFP levels >5 ng/mL in up to 18% of EACs, with the highest reported AFP level being 320ng/mL. However, to the best of our knowledge, our case is only the 14th AFP-producing EAC to be thoroughly described in the English literature. Patients with EAC and cirrhosis often share common risk factors that make the differential diagnosis of liver masses and elevated AFP challenging. Some AFP-producing EACs contain cells resembling hepatic cells and are termed hepatoid EAC. Although not possible in our case, serial measurement of serum AFP level may be useful for monitoring clinical status and response to treatment. Most cases are treated with surgery and adjuvant chemotherapy but with disappointing results given the advanced presenting stage, high liver metastatic potential, and poor prognosis of AFP-producing EAC.Figure 1Figure 2Figure 3