Risk analysis of torsion and malignancy for adnexal masses during pregnancy

Objective: To find the risk factors of torsion and malignancy for adnexal tumors during pregnancy. Design: Retrospective, historical cohort study. Setting: University hospital. Patient(s): Patients from 1990 to 2004 with adnexal tumors ≥4 cm during pregnancy. Intervention(s): Surgery undertaken antepartum, concurrently with cesarean delivery, or postpartum. Main Outcome Measure(s): Tumor size, progression, pathology, incidence of malignancy, and torsion. Result(s): Almost all 213 managements analyzed had good surgical and obstetric outcomes. In 174 patients who were followed through pregnancy with known tumor existence, 14.84% ± 3.05% encountered tumor torsion. Adnexal masses with sizes between 6 and 8 cm had a significantly higher risk of torsion compared with other sizes (22.41% vs. 9.48%; odds ratio 2.8, 95% confidence interval [CI], [1.1, 6.6]). Sixty percent of the torsion happened between the 10th and 17th weeks of gestation, and only 5.9% happened after 20 weeks. The incidence of malignancy was 3.4%, while that of ovarian cancer was 2.3%. Tumor diameters ≥10 cm at initial diagnosis had a higher risk of malignancy versus smaller sizes (8.77% vs. 0.85%; odds ratio 11.2, 95% CI, [1.3, 97.9]), and tumor growth rates ≥3.5 cm/week also had a significantly higher risk of malignancy versus lower rates (8.33% vs. 0.88%; odds ratio 10.2, 95% CI, [1.0, 101.2]). Conclusion(s): Adnexal tumors bearing higher risks for torsion and malignancy should be strongly considered for an aggressive strategy of management during pregnancy.