Preoperative sonographic features of borderline ovarian tumors

To determine the sonographic findings that distinguish borderline ovarian tumors (BOT) from both benign and invasive malignant tumors, thus allowing conservative treatment and laparoscopic management of these tumors.

We reviewed retrospectively transvaginal sonograms of 33 women who, when evaluated further by surgery and histology, were found to have BOT. Twenty-three were premenopausal and 10 were postmenopausal (mean age +/- SD, 45.8 +/- 15.7 years). For each mass, size and morphological features and power Doppler characteristics were evaluated. We compared these findings with those of 337 patients with benign ovarian tumors and those of 82 patients with invasive malignant ovarian tumors. Patients with dermoid cysts were not included in the study.

Of the 33 BOT, 15 were mucinous and 18 were serous cystadenomas. The presence of papillae, defined as a small number of solid tissue projections, 1-15 mm in height and 1-10 mm in width (base) and length (base), into the cyst cavity from the cyst wall, was significantly more frequent in BOT (48%) than it was in benign (4%) and invasive (4%) malignant tumors. Intracystic solid tissue (> 15 mm in height or > 10 mm in width or length) was observed in 48% of invasive malignant masses but in only 18% of BOT and in 7% of benign tumors (P < 0.001). No sonographically unilocular, hypoechoic, smooth-walled adnexal cysts were invasively malignant but three unilocular cysts with a diameter of > 6 cm were serous BOT. Although close attention was paid to the cyst wall at ultrasound examination we did not observe in these three cysts the very small papillae which were found at histological analysis.

The most frequent diagnostic feature on imaging BOT is the presence of papillae within the cyst. However, neither papillae nor other sonographic features constituted highly sensitive sonographic markers of BOT.