A case of Schistosomiasis Japonicum with a submucosal tumor in the cecum was experienced. The patient was 65-years old female, and had ever lived in the Kofu basin, Yamanashi prefecture. She was suffering from constipation, and had the colon scopy performed. A submucosal tumor in 2cm diameter was found in the cecum. With endoscopic ultorasonography, the thickening of the second layer with focal hyper echoic lesion was observed. The surface of the tumor got depressed in six months with endoscopic findings. To confirm the pathological diagnosis and for the therapy, laparoscopic local resection of the cecum was performed. Microscopically, the eggs of Schistosoma Japonica and the aggregation of lymphocytes and histiocytes around the eggs were observed. With immunohistochemical examination, diffuse spledding of the CD4, CD8, CD20, and CD45 positive lymphocytes were observed. The chronic inflammation of the cecum was observed as submucosal tumor.
