Ultrasonographic diagnosis and longitudinal follow-up of recurrences after conservative surgery for borderline ovarian tumors

Background Borderline ovarian tumors are generally diagnosed in young women. Because of the young age of patients at first diagnosis and at recurrence, and given the good prognosis of borderline ovarian tumors, a conservative surgical approach in those women who wish to preserve their fertility is advised. In this scenario, transvaginal ultrasound examination plays a key role in the detection of borderline ovarian tumor recurrence, and in assessment of amount of normal functioning parenchyma remaining. To date, no data are available about the natural history of borderline ovarian tumor recurrence. Objective The aim of the study was to determine growth rate of recurrent ovarian cysts by a scheduled follow-up by ultrasound examination, in women previously treated with fertility-sparing surgery due to borderline ovarian tumors. Study Design In this prospective observational study, we collected data from 34 patients previously treated with fertility-sparing surgery due to borderline ovarian tumors, who had a suspicious recurrent lesion. The patients underwent transvaginal ultrasonographic examination every 3 months, until the clinical setting recommended proceeding with surgery. According to cyst size at study entry, they were categorized into 3 groups: ≤10 mm, 10-20 mm, and >20 mm. Summary statistics for cyst size, growth rate, and the probability of remaining within the same dimension category at first ultrasound during the follow-up were also obtained. For each cyst the growth rate was calculated as the slope of the linear interpolation between 2 consecutive measurements. Results Follow-up timing (P <.001), cyst size (P <.001), and micropapillary pattern (P <.001) were factors significantly affecting the cyst growth both in univariate and multivariate analysis. According to size category at first ultrasound, growth rate ranges from a minimum of 0.06 mm/mo for cysts <10 mm up to 1.92 mm/mo for cysts >20 mm. The final histology of all recurrent lesions confirmed the same histotype of primary borderline ovarian tumors. Conclusion This article represents the first observational study that describes the trend in the growth rate of borderline ovarian tumor recurrence in relation to their size detected at the first ultrasound examination. The findings of this study seem to confirm, in selected patients, that a thorough ultrasonographic follow-up of borderline ovarian tumor recurrence has proven to be safe and feasible. The final goal of such management is to maximize the impact on fertility potential of these young women without worsening their prognosis.