Disseminated peritoneal adenomucinosis associated with a panperitonitis-like onset: Report of a case

A 59-year-old man was admitted to our department due to a fever of unknown origin. Abdominal ultrasonography and computed tomography showed a large cystic mass in the lower abdomen and a massive amount of abdominal fluid. A laparotomy was performed under a diagnosis of panperitonitis. Diffuse pyogenic gelatinous ascites and a large cystic mass with a grayish wall, and a hard solid lesion in part were found. The microscopic findings of the hard solid lesion showed calcification, osteogenesis, and focal epithelial proliferation in a tiny area consisting of mucinous cells with no significant cytologic atypia. The remaining part of the cystic wall and small cystic lesions were hyalinized, fibrous, or necrotic tissue. Since a total resection of the masses was not possible, the patient received adjuvant chemotherapy with cisplatin followed by the administration of mitomycin C and 5-fluorouracil. An abdominal fistula with the excretion of pyogenic gelatinous fluid occurred, but the patient is still alive and doing well over 2 years postoperatively. The primary site of this tumor could unfortunately not be identified.