Villous Mucinous Cystadenoma of the Appendix in a Postmenopausal Woman

Objective: To present the case of a postmenopausal woman, who was suspected of having an ovarian cyst. Instead, a cystadenoma of the appendix was discovered during laparoscopy. Methods: A 64-year-old postmenopausal nulliparous woman was admitted to our hospital because of a cystic lesion, which had been detected in the course of a routine gynecological examination. The patient underwent vaginal ultrasound, magnetic resonance tomography, and laparoscopy. Results: During vaginal ultrasound, a dumbbell-shaped anechogenic cystic structure 70 x 32 x 22 mm in diameter was found in the region of the right adnexa. Magnetic resonance tomography revealed no additional information. During diagnostic laparoscopy, the cystic lesion was found to be a distended appendix. A laparoscopic appendectomy was performed. Subsequent histological analysis revealed a villous mucinous cystadenoma of the appendix with low-grade intraepithelial neoplasia. Conclusion: Gynecologists should routinely consider this disease in the differential diagnosis of right lower dumbbell abdominal cysts. Eleven percent to 20% of mucoceles are caused by mucinous cystadenocarcinomas, which carry the risk of peritoneal tumor implantation caused by rupture or laparoscopic resection. Therefore, it should be mandatory that a general surgeon be involved in the laparoscopic procedure and the conversion to laparotomy for resection of the structure.