[Appendiceal mucocele mimicking right adnexal mass: a report of 25 cases]

To explore the differential diagnosis and pertinent treatment of women with right lower quadrant abdominal mass.

The clinical data of 25 women patients with appendiceal mucocele at our hospital from 2000 to June 2010 were recorded. And their clinical presentations, auxiliary examinations and treatment were analyzed retrospectively with the SPSS17.0 software.

Among 1157 women undergoing appdicelectomy at our hospital, 25 (2.16%) had appendiceal mucocele. Their mean age was 58.2 years old. Their presenting symptoms and signs were non-specific. Ten cases (40%) were misdiagnosed as adnexal mass. The mass could be palpable by pelvic examination in 80% cases while 66.7% by abdominal examination. For preoperative auxiliary examination, the correct rate of ultrasonogram was 54.2% and CT 60%. The positive rate of carcinoembryonic antigen (CEA) was 57.1% while that of carbohydrate antigen 19 - 9 (CA199) 18.2%. Neither had statistical significance. There were three pathological entities: mucinous cystadenoma, malignant mucinous cystadenocarcinoma and simple retention mucoceles. Because of incidental discovery, the treatment remained variable. The approaches included appendectomy, cecectomy, right hemicolectomy and debulking according to the frozen pathological examination.

As a rare condition, appendiceal mucocele is usually misdiagnosed as right adnexal lesion. Because of its anatomic position, it should be considered in the differential diagnosis of adnexal masses. Auxiliary examinations such as ultrasonogram, computed tomography and serum CEA may be helpful for its diagnosis. Its optimal management is achieved through an accurate preoperative identification and subsequently careful resection.