Blood flow characteristics of ovarian tumors: implications for ovarian cancer screening

Our purpose was to investigate the blood flow characteristics of benign and malignant ovarian tumors. Questions posed by our research were as follows: (1) Can malignant ovarian tumors be predicted by color flow Doppler imaging? (2) What are the sensitivity, specificity, and positive and negative predictive values of such prediction? (3) Which color flow Doppler parameter is superior in its accuracy of prediction?

One hundred twenty-three consecutive patients seen for suspected pelvic masses were evaluated by transvaginal ultrasonography and color flow Doppler imaging. A morphologic assessment was initially performed, followed by color flow Doppler analysis. A comparison of findings between the benign and malignant tumors was made by analyzing different thresholds of the intratumoral pulsatility and resistance index values by means of receiver-operator characteristic curves. By calculation of the area index under each receiver-operator characteristic curve the efficiency of the pulsatility and resistance index values in predicting malignancy was determined.

Fifty-six benign and 23 malignant tumors were pathologically confirmed. Patients with malignant tumors were more likely to be postmenopausal and were older than patients with benign tumors. Malignant tumors were more likely to be larger and to have either a complex or solid pattern. Absent color flow was more common in benign tumors, and increased color flow was found equally among benign and malignant tumors. There was no difference in systolic, diastolic, or mean velocities between benign and malignant tumors. The calculated pulsatility and resistance index values were lower in patients with malignant tumors compared with those with benign tumors. No significant difference exists in performance of either the pulsatility or resistance index in predicting malignancy. The best thresholds for predicting malignancy were obtained with a pulsatility index of 1.0 and resistance index of 0.6.

Transvaginal ultrasonography is accurate in distinguishing benign from malignant ovarian tumors. Color flow Doppler findings are not specific enough to be used independent of gray-scale ultrasonography.