NAPSA and esophageal adenocarcinoma: We detected positive immunohistochemical staining with antibodies against Napsin A (IP64 clone) in 3 out of 125 esophageal adenocarcinomas (2.4%), and 4 out of 419 gastric adenocarcinomas (1%), while no adenocarcinoma of colorectal origin presented with Napsin A positivity.