Fig. 3

Pathological findings of the tumor. a, macroscopic findings: the tumor is located mainly in the submucosa, and two cysts are observed within the tumor; b–d, microscopic examination (hematoxylin and eosin staining on three different power fields) showing a partial epithelial lining in the cyst wall and some glandular structures within the tumor. Spindle tumor cells are seen in the rich myxoid stroma. The tumor cells are positive for alpha-smooth muscle actin (e) and negative for c-KIT (f)