Differentiation between benign and malignant ovarian tumours by ultrasonography

A prospective non-randomized study was carried out during 2002-2003 in the Departments of Radiology & Imaging and Obstetrics & Gynaecology, Tribhuvan University Teaching Hospital, Maharajgunj, Kathmandu. Fourty five patients with ovarian masses underwent ultrasonographic examination. These masses were given certain scores according to the different morphological features and were classified as benign and malignant. The sonographic findings were correlated with the histopathological reports. Of 45 patients, 31 had benign and 14 had malignant ovarian tumours. Ultrasonographic differentiation of benign and malignant ovarian tumours showed good results with a sensitivity of 85.7%, specificity of 83.8%, and positive and negative predictive values of 70.5% and 92.8%, respectively. The result of the study was statistically significant (p = 0.00004). Among different features, thin (less than 3 mm) wall, smooth inner wall structure and anechogenicity or low echogenicity of the lesions were more reliable predictors of benignity. Highly echogenic lesions with solid component(s), without demonstrable and measurable wall and indistinct inner wall structure suggested malignancy. The ultrasonographic characterization by scoring system was useful in distinguishing benign from malignant masses.