Abstract
A 84-year-old female (A) and 61-year-old male (B) with no abdominal symptoms were admitted to our hospital suffering from pneumonia and diabetes mellitus, respectively. In the ileocecal region of each patient a painless large egg-sized tumor was palpable. Colonoscopy, ultrasonography and computed tomography suggested the tumors to be appendiceal mucoceles. A fistula was made endoscopically between the cecal wall and the tumor capsule in both cases by cauterizing with microwave. In the case A, a colonoscope was inserted through the fistula and biopsies were obtained from the inner wall of the tumor capsule. In the case B, tissue specimens were also obtained successfully from the mucocele wall by blind endoscopic biopsy because the caliber of the fistula was not so large enough as to insert the colonoscope into the tumor lumen. On the biopsy specimens both lesions were revealed histologically to be appendiceal mucinous cystadenoma. Both patients had a good clinical course without any complications such as perforation or bleeding at the sites of fistulation and biopsy. It is occasionally difficult to differentiate mucinous cystadenoma from mucinous cystadenocarcinoma by imaging examination. The biopsy technique tried on our cases may, therefore, be appreciated as an usefull tool for correct diagnosis of appendiceal mucocele and for deciding the way of surgery.
