An Extremely Rare Case of Adenoma Malignum with Large Cystic Tumor Which Resulted in Urinary Obstruction

Abstract Background. Adenoma malignum is a rare variant of uterine cervical adenocarcinoma. In this report, we present an extremely rare case of adenoma malignum with large cystic lesions (diameter of more than 10 cm) which elicited urinary obstruction. Case. A 46-year-old Japanese woman, gravida 2, para 2, visited her local doctor for urinary obstruction, and 950 ml of urine was catheterized. Since abdominal ultrasonography suggested ovarian cystic tumor, she was referred to our hospital. Vaginal examination and ultrasonography revealed a child-head-sized multilocular cystic tumor in the Douglas pouch. Abnormal massive discharge was not observed at the time of admission. During preoperative examination, massive mucinous discharge suddenly occurred without pain. The cystic tumor size shrank from ×10 cm to ×4.0 cm in maximum diameter. Emergent abdominal hysterectomy was performed. The operative findings revealed collapsed cystic lesions in the posterior wall of the uterine cervix. Microscopically, the multiple cysts in the cervix were composed of high columnar and slightly atypical monolayer cells similar to endocervical mucinous cells. Vaginal invasion was also partly observed. Most of the tumor cells were positive for carcinoembryonic antigen and HIK1083 in their cytoplasm, and scattered chromogranin A-positive endocrine cells were also found in tumor glands, corresponding to minimal deviation adenocarcinoma (adenoma malignum). These lesions were diagnosed as FIGO stage IIa. The patient is disease-free 2 years after primary surgery. Conclusion. In the present report, we describe an extremely rare case of adenoma malignum with large cystic lesions reaching a diameter of 12 cm which resulted in urinary obstruction.