The Ultrasonography Characteristics of Borderline Ovarian Tumor Subtypes

Abstract

Borderline ovarian tumors, which are of epithelial origin, exhibit malignant histological features without stromal invasion. They differ from invasive ovarian carcinomas since often diagnosed in younger patients, at an early stage, and have a more favorable prognosis. This allows a more conservative surgical approach for some patients who desire fertility‐sparing surgeries. Grayscale, color and power Doppler ultrasonography are the initial imaging modalities for characterizing adnexal masses and evaluating their risk of malignancy. This review summarizes the main sonographic features of borderline ovarian tumors that are useful for pattern recognition.

Keywords: borderline tumor; ovarian epithelial carcinoma; ovarian neoplasm; ultrasound.

Figure 1

Serous ovarian tumors. Serous borderline ovarian tumors usually appear on ultrasonography Doppler imaging as cystic lesions with numerous vascularized papillary projections (A–F). Rarely, however, they may show an exophytic growth pattern with predominantly solid tumors that exhibit rich hierarchical vascular branching (i.e., a fireworks sign; G). Serous low‐grade ovarian cancer (H, I) often presents as irregular solid lesions with exophytic growth (H) or cystic lesions with endophytic papillary projections (I). Hyperechoic foci representing small calcifications may also be present (yellow arrows in I).

Figure 2

Mucinous borderline ovarian tumors. Mucinous borderline ovarian tumors are mostly unilateral, large multilocular cystic lesions containing more than 10 locules (A–D) with scattered low‐level echogenicity. Honeycomb nodules may be present (E–H). Rarely, a solid component may be visualized (yellow star in H).

Figure 3

Pseudomyxoma peritonei. Pseudomyxoma peritonei often appears as echogenic ascites with diffused septations (green arrows in A and red triangles in B) and centrally displaced fixed bowels (yellow star in B).

Figure 4

Seromucinous borderline ovarian tumors and differential diagnosis. Seromucinous borderline ovarian tumors are often cystic lesions with numerous vascularized papillary projections and ground‐glass cyst echogenicity, reflecting their association with endometriosis (A–D). Notably, in the differential diagnosis, atypical endometrioma may present as a cystic lesion with ground‐glass cyst echogenicity and papillary projections; however, it usually does not show vascular flow on Doppler imaging (E). In contrast, decidualized endometriomas during pregnancy may also contain papillary projections that are almost always highly vascularized on Doppler imaging (F).

Figure 5

Rare borderline ovarian tumors. Clear cell and endometrioid BOTs are predominantly large solid tumors with small to large cystic areas on macroscopic examinations. Indeed, both the clear cell (A) and endometrioid (B) BOT cases showed large solid components with cystic areas and high vascular flow on Doppler imaging. Brenner BOTs macroscopic appearance is often described as cystic lesions with papillary projections. In this case (C), a cystic lesion with what appears to be a large papillary projection is present.

Figure 6

Borderline ovarian tumors and microcystic pattern. Ultrasonography microcystic pattern on grayscale (top row) and 3D‐silhouette mode (bottom row) in serous borderline (A), seromucinous borderline (B), and mucinous borderline ovarian tumors (C).

Figure 7

Differential diagnosis of borderline tumors with microcystic pattern. Ultrasonography grayscale (top row) and 3D‐silhouette mode (bottom row) of ovarian tumors presenting the microcystic pattern (white arrows) in benign cystadenofibroma (A), benign struma ovarii (B), and malignant invasive endometrioid carcinoma (C).

Figure 8

Example of microvascular imaging presenting extremely small, thin blood vessels of the size of arterioles in a borderline ovarian tumor using a 9–5 MHz transvaginal ultrasound transducer set to a pulse repetition frequency of 0.18 kHz.

Figure 9

Ultrasound imaging of serous borderline ovarian tumor using radiant color Doppler US (CDUS) with a PRF of 0.6 kHz and microvascular imaging (MVI) using a PRF of 0.21 kHz. Note the difference in the details of the vascular patterns.

Figure 10

Ultrasound imaging of mucinous borderline ovarian tumor by radiant color Doppler US (CDUS) using a PRF of 0.6 kHz and microvascular imaging (MVI) using a PRF of 0.21 kHz. Note the difference in the details of the vascular patterns.