A 67-year-old female who complained of abdominal distention and epigastralgia was admitted to our hospital. Barium enema and colonoscopic examination revealed a submucosal tumor that measured about 50x48x30mm in the rectum. Since the possibility of malignancy could not be excluded, the tumor was removed by lower anterior resection.
Histological examination showed that the tumor was composed of fibroblast-like spindle-shaped cells and the characteristic of nuclear palisading was observed. Immunohistochemical staining showed that the tumor cells were positive for S-100 protein, vimentin, but negative for actin, smooth muscle actin and desmin. Based on histological findings and the result of immunohistochemical staining, a diagnosis of neurilemoma was made.
