Risk of torsion and malignancy by adnexal mass size in pregnant women

Abstract

Objective: To investigate risks of torsion and malignancy by adnexal mass size during pregnancy.

Design: Retrospective review of medical records.

Setting: General university hospital and healthcare center.

Population: Four hundred and seventy women who underwent surgery for adnexal masses during pregnancy between 2002 and 2009.

Main outcome measures: Rate of torsion and malignancy according to mass size classified into four groups: <6, 6-10, 10-15 and ≥15 cm.

Results: Torsion was encountered in 55 patients (11.7%) and malignancy was confirmed in 20 (4.3%). A mass size of 6-10 cm had a significantly higher risk of torsion than a mass <6 cm (odds ratio 2.68, 95% confidence interval 1.33-5.40, p=0.006). Masses ≥15 cm had an approximately 12-fold higher risk of malignancy compared with masses <6 cm (odds ratio 12.36, 95% confidence interval 2.90-52.67, p=0.001). However, for masses of 10-15 cm, the risks of both torsion and malignancy were not higher than those of masses <6 cm.

Conclusions: Risks of torsion and malignancy are not directly proportional to increasing mass size in pregnant women. Physicians should be aware of a high risk of malignancy in women with an adnexal mass of over 15 cm. However, if a mass is smaller, the size should not be considered as a single independent factor in a decision for surgery.