Long-term Results for Expectant Management of Ultrasonographically Diagnosed Benign Ovarian Teratomas.

OBJECTIVE

To assess the natural history of ultrasonographically diagnosed benign ovarian teratomas in asymptomatic women.

METHODS

We conducted a retrospective observational cohort study of 408 women (mean age 36.6 years, range 14-81 years) diagnosed as having an ovarian teratoma by transvaginal ultrasonography (except eight who only had a transabdominal study done) between January 2003 and December 2013 at a single tertiary care institution. Six hundred thirteen women were diagnosed with ovarian teratoma of whom 205 were promptly treated surgically, leaving 408 patients followed conservatively with follow-up scans at 3 and 6 months from diagnosis and then yearly. The ultrasonographic diagnosis of a benign ovarian teratoma required at least one of the following features: a cystic mass with mixed echogenicity, thick band-like echoes, a fat-fluid level, or echogenic tubercle with posterior shadowing. Clinical, ultrasonographic, and histologic data (in case of surgery) were retrieved for analysis.

RESULTS

During follow-up, 130 of 408 (31.8%) women underwent surgery. The main reason for surgery was the physician's recommendation according to our protocol (n=115). One patient had adnexal torsion. Most surgeries (112/130 [86.2%]) were performed within the first 5 years after diagnosis. The remainder (278/408) is still being followed (median time 45.6 months, range 6-147 months). The vast majority of these lesions had no change and women remain asymptomatic. Histologic diagnosis of tumors removed surgically revealed a benign ovarian teratoma in 103 of 130 (79.2%) of the women. There were two borderline tumors, four endometriomas, three fibromas, seven serous cysts, two mucinous cysts, two stroma ovarii, seven other benign, and no case of malignant tumor.

CONCLUSION

Our results demonstrate that expectant management might be a reasonable option for managing asymptomatic women who receive a ultrasonographic diagnosis of a benign ovarian teratoma. The risk of undergoing surgery for this lesion decreases significantly after 5 years to follow-up. With careful observation, the risk of missing a diagnosis of malignancy is low.