A case of cesarean scar disorder with a chocolate cyst-like mass of 6 cm in diameter

Abstract

　A 41-year-old woman with a history of two cesarean sections visited our department complaining of dysmenorrhea, prolonged menstruation, and dyspareunia. Pelvic transvaginal ultrasound and Magnetic Resonance Imaging (MRI) confirmed a chocolate cyst-like mass approximately 6 cm in diameter in the vesicouterine pouch. Since a fistula-like finding was observed at the cesarean section scar, we suspected that a uteroperitoneal fistula formed by accumulation of menstrual blood in the vesicouterine pouch through this fistula. There are reports of fistula closure by pseudomenopause therapy as a treatment for vesicouterine and uteroperitoneal fistula. Four months after starting administration of leuprorelin acetate, the patient presented with a chief complaint of fever. A large amount of pus was found in the cyst and uterine cavity, and culture confirmed the presence of Escherichia coli. The symptoms and findings were alleviated with combined administration of antibiotics and transcervical drainage. Laparoscopic hysterectomy was performed because the fistula could not be closed with this treatment. Based on intraoperative observations and examination of resected samples, uteroperitoneal fistula was ruled out, and cesarean scar disorder (CSDi) was diagnosed in which the cesarean scar expanded like a chocolate cyst.

　CSDi can sometimes involve formation of a chocolate cyst-like mass in the vesicouterine pouch, and must be differentiated from uteroperitoneal fistula. For similar cases, cesarean scar repair is performed if maintenance of fertility is desired, and hysterectomy is performed if maintenance of fertility is not desired.