Fig. 5

Microscopic findings of resected specimens. a The tumor was composed of moderately differentiated invasive PDAC, and carcinoma in situ and high-grade pancreatic intraepithelial neoplasia surrounded the tumor (white arrow). b Glandular fossa epithelium and gastric fundic gland were observed on the luminal side of the GDC, and mucosal muscle plate and muscle layer were also observed. c The fistula between the GDC and pancreas was histopathologically observed (black arrow)