Dermoid cyst management and outcomes: A review of over 1,000 cases at a single institution.

BACKGROUND: Mature cystic teratomas represent nearly 60% of benign ovarian neoplasms across all age groups. We aim to update existing descriptive studies of ovarian teratomas including the epidemiology, rate of torsion/malignancy, and treatment modalities in a large modern cohort of patients.

STUDY DESIGN: This is a retrospective cross-sectional study of all pathology-confirmed cases of ovarian teratoma who underwent surgery at one tertiary care institution from 2004-2015. Patient demographics, ovarian cyst characteristics, surgical approach and timing, rate of spillage, and surgical complications were examined.

RESULTS: 1,054 cases of ovarian teratoma were identified during the study period. There were 113 cases of bilateral teratoma (10.7%). Mean age at diagnosis was 38 years. Average cyst size was 6.26cm. The overall rate of torsion was 5.6%, with a higher rate of torsion with increasing cyst size. Over 70% of cases were treated with minimally invasive surgery, which was associated with decreased perioperative complications but an increased risk of cyst spillage. Among 394 patients with cyst spillage, only one developed chemical peritonitis. The malignant transformation rate of mature cystic teratoma in this cohort was 1.1%. This cohort included 100 pregnant women with mature teratoma. Pregnant patients were more likely to have minimally invasive surgery in the 1st trimester and more likely to undergo laparotomy in the 2nd or 3rd trimester.

CONCLUSIONS: In this large modern cohort, we found similar rates of bilaterality, torsion, malignant transformation, and struma ovarii in ovarian teratomas when compared to previous literature. Most cases of ovarian teratoma can be managed laparoscopically, which is associated with a lower surgical complication rate. Despite increased risk of cyst spillage with a minimally invasive approach, chemical peritonitis is a rare complication.