Transvaginal colour flow imaging: a possible new screening technique for ovarian cancer.

Abstract
OBJECTIVE--To assess whether changes in the intraovarian vasculature or blood flow impedance can be used to identify potentially malignant masses. DESIGN--Open, non-comparative prospective study. SETTING--Ovarian screening clinics at King's College Hospital and the Hallam Medical Centre. SUBJECTS--50 Women selected on the basis of their medical history and the result of a previous transvaginal ultrasound scan. Thirty women (10 premenopausal (scan taken on days 1 to 8 of the menstrual cycle) and 20 postmenopausal) had normal ovaries, and 20 had at least one ovary with an abnormal morphology or volume, or both. INTERVENTIONS--Women with a positive result on screening were referred for laparotomy. MAIN OUTCOME MEASURES--Presence or absence of coloured areas (neovascularisation) and the pulsatility index within each ovary. The pulsatility index is a measure of the impedance to blood flow, a low value indicating decreased impedance and a high value increased impedance to blood flow. RESULTS--Two women with a positive result on screening had hydrosalpinges, 10 a benign tumour or a tumour-like condition, and eight primary ovarian cancers. No areas of neovascularisation were seen in the 30 women with morphologically normal ovaries and the two patients with hydrosalpinges; the pulsatility index ranged from 3.1 to 9.4. Similarly, nine patients (10 affected ovaries) with a non-malignant mass had no signs of neovascularisation and the pulsatility index varied from 3.2 to 7.0. One patient with bilateral dermoid cysts containing nests of thyroid-like cells had vascular changes and pulsatility index values of 0.4 and 0.8. Seven patients (eight ovaries) with primary ovarian cancer (one stage IV, four stage II, and two stage Ia) showed clear evidence of neovascularisation and pulsatility index values were from 0.3 to 1.0. One patient with an intraepithelial serous cystadenocarcinoma in a small ovary (less than 5 ml volume) had no signs of any vascular change and the pulsatility index was 5.5. CONCLUSION--Transvaginal colour flow imaging may be used to identify potentially malignant ovarian masses and help elucidate the early stages of tumorigenesis. The routine application of this technique may reduce the rate of false positive results of an ultrasonography based screening procedure.