Ovarian cyst with torsion presenting as a wandering mass in a newborn

A case of ovarian serous cystadenoma with torsion presenting as a wandering abdominal mass is reported. A full-term baby girl was noted to have a left pelvic cyst by prenatal ultrasound at the 34th gestational week. After delivery, a series of work-ups, including ultrasonography and CT scan, revealed a cyst with fluid-debris level in the right pelvis. An ovarian cyst with torsion was suspected and surgical intervention was done when she was 7 days old. The operative findings confirmed a left ovarian cystic mass with torsion. A left salpingo-oophorectomy was performed smoothly. Pathology revealed the typical microscopic findings of ovarian serous cystadenoma, a benign epithelial tumor of ovary. We suggest that a wandering ovarian cystic mass in female fetus and newborn should be considered an indication for surgical intervention due to its high risk of torsion.