A COMPARISON OF INTRATUMORAL INDEXES OF BLOOD-FLOW VELOCITY AND IMPEDANCE FOR THE DIAGNOSIS OF OVARIAN-CANCER

The aim was to assess the value of blood flow velocity indices in an u ltrasound-based test to discriminate between malignant and benign adne xal tumours. Fifty-one women (35 premenopausal and 16 postmenopausal) with persistent adnexal masses were scanned prior to surgery using tra nsvaginal sonography with colour Doppler imaging. Intratumoural flow v elocity waveforms obtained by pulsed Doppler sonography were used to d etermine the time averaged maximum velocity (TAMXV), peak systolic vel ocity (PSV), pulsatility index (PI) and resistance index (RI). The tum ours were classified by histologic criteria (42 benign, 1 borderline a nd 8 malignant tumours). Two of the malignant and the single borderlin e tumour were stage I, five were stage III and one was stage IV. Detec table blood flow signals were found in all malignant and borderline tu mours and in 33 of 42 (78.6%) of the benign tumours. TAMXV was the bes t parameter for discrimination of benign and malignant adnexal patholo gy and at a cut-off value of TAMXV greater than or equal to 12 cm/s to indicate malignancy, the sensitivity and specificity were 88.9% and 8 1.0%, respectively. At the same sensitivity level, this gave a better specificity than the PI less than or equal to 0.90 (specificity 61.9%, P = 0.036), RI less than or equal to 0.60 (specificity 54.8%, P = 0.0 10) and PSV greater than or equal to 16 cm/s (specificity 71.4%, P = 0 .121). Discrimination between benign and malignant tumours was improve d further by using two criteria rather than one. When the two criteria of a TAMXV of greater than or equal to 12 cm/s and a PI less than or equal to 1.0 were applied simultaneously, the tumours could be charact erised with a sensitivity of 88.9% and a specificity of 88.1%. Therefo re, intratumoural PSV and TAMXV could be used to discriminate between benign and malignant adnexal tumours better than values for PI and RI. The best discrimination was achieved by using a combination of cut-of f values for velocity and impedance parameters as two criteria to defi ne malignancy.