Ultrasound characteristics of different types of adnexal malignancies

Abstract

Objective. To describe ultrasound characteristics of adnexal malignancies, i.e., borderline ovarian tumors, primary invasive ovarian epithelial cancer stage 1, primary invasive ovarian epithelial cancer stages 2–4, rare types of malignancy, and metastatic tumors. Methods. In a prospective international study involving nine European ultrasound centers, 1066 women with a pelvic mass judged to be of adnexal origin underwent transvaginal gray scale and color Doppler ultrasound examination by a skilled examiner before surgery. A standardized examination technique and predefined definitions of ultrasound characteristics were used. Results. Of 1066 masses, 266 were malignant and are included: 55 ovarian borderline tumors, 144 primary invasive epithelial ovarian cancers (42 stage 1, 102 stages 2–4), 25 rare malignancies, and 42 metastatic tumors. Most (56%) metastatic tumors and most (60%) rare types of tumor were solid and richly vascularized at color Doppler ultrasound examination (on a scale ranging from 1 to 4, color score based on subjective evaluation was 3 or 4 in 88% and 86%, respectively). Borderline ovarian tumors and stage 1 primary invasive ovarian epithelial cancers differed from stages 2–4 primary invasive ovarian epithelial cancers: they were larger (median volume 375 ml and 695 ml vs. 209 ml; P = 0.0213 and 0.0001), a larger proportion contained papillary projections (64% and 67% vs. 41%; P = 0.0072 and 0.0054), they were more often multilocular cysts without solid components (18% and 14% vs. 2%; P < 0.0017 and 0.0204), but they were less often purely solid (5% and 7% vs. 38%; P ≤ 0.0001 and 0.0005). With increasing degree of invasiveness – from borderline epithelial ovarian tumors via stage 1 invasive epithelial ovarian tumors to stages 2–4 invasive epithelial ovarian tumors – ascites became more common (9% vs. 31% vs. 61%; P = 0.0082, <0.0001, and 0.0017), and, among tumors with solid components ( n = 179), the proportion of tumor consisting of solid tissue increased (median 2%–10%–34%; P = 0.0212, <0.0001, and 0.0003). Conclusion. Papillary projections are characteristic of borderline tumors and stage 1 primary invasive epithelial ovarian cancer. A small proportion of solid tissue at ultrasound examination makes a malignant mass more likely to be a borderline tumor or a stage 1 epithelial ovarian cancer than an advanced ovarian cancer, a metastasis, or a rare type of tumor.