Fig. 3

Histological findings with HE staining. a Photomicrograph showing a sac-like structure within the muscularis propria. The structure is a true diverticulum protruding from the small intestine (dashed yellow line). The cancerous area is shown as a Square b, and the cancer and adjacent tissue as Square c. b Photomicrograph showing atypical columnar epithelium that has grown in a tubular manner in the mucous membrane of the diverticulum. c Photomicrograph showing an enlarged space covered by flattened atypical cells in the tissue of Meckel’s diverticulum and in contact with the cancer. This tissue is suggestive of ectopic pancreas. There is no gastric mucosa, intestinal mucosa, acinar cell, or islets of Langerhans. HE, hematoxylin and eosin