A52

Ovarian cancer is a heterogeneous group of malignancies that can remain asymptomatic despite being at an advanced stage, or cause non-specific symptoms . In about 70% of patients, ovarian cancer is diagnosed at an advanced stage, leading to a poor prognosis: in Europe, in the 1990s, the average age-adjusted 5-year survival of ovarian cancer patients was 37% (2). Non-invasive discrimination between benign and cancerous ovary and detection of ovarian cancer at an early stage remain challenging. Studies in women at higher risk of developing an ovarian cancer based on interpretation of sonographic images and measurement of serum CA 125 antigen do not succeed in improving the detection of ovarian cancer at an earlier stage (9). Serum CA 125 level and various other clinical and patient-related parameters are less effective than judgment of an expert ultrasound operator, and TVS(Trans Vaginal Sonography) done by expert ultrasound operators have an average sensitivity of 85% (range 70-98%) and specificity of 85% (range 77-96%) (10,11). HistoScanningTM is an innovative computer aided diagnostic (CAD) technology designed to be an adjunct to three-dimensional (3D) ultrasonography systems. The first application derived from the HistoScanning technology was intended for the detection of ovarian cancer and was labeled "Ovarian HistoScanning" (OVHS). OVHS was conceived for enabling non-invasive discrimination between cancerous and non-cancerous lesions of ovaries. This article provides a brief description of the OVHS technology and presents results of a prospective clinical study that made a first appraisal of the usefulness of OVHS for the assessment of ovarian masses. In a recent multi center study, acquisition of adequate voxel data during three-dimensional (3D) TVS performed before surgery was done for a total of 269 eligible ovaries removed from 228 women 26-86 years of age in five European institutions. Voxel data were analyzed using OVHS while being blind to the coresponding pathology. After surgery, results from OVHS and histology were compared. Histology reported 173 non cancerous ovaries 87 normal, 87 benign tumors, 2 non cancerous pelvic masses and 93 cancers 54 were ovarian carcinoma, 21 were borderline ovarian cancer, 10 were ovarian carcinomatosis. Among the 8 others three were metastases from melanoma (2) and colon (1), three were local invasion by a pseudomyxoma peritonei, a fallopian tube cancer and a leiomyosarcoma, two were carcinomatosis of unknown origin. 92 cancers were correctly identified by OVHS representing a sensitivity of 99%. The false negative result was a case of cystadenofibroma with microscopic foci of borderline cancer. All FIGO stages were correctly identified. The overall specificity of OVHS was 77%. Nevertheless, when the voxel acquisition gain level was maintained below -4 dB as recommended by the OVHS data acquisition protocol, the OVHS specificity increased to 92% without affecting sensitivity.

[Fifth AACR International Conference on Frontiers in Cancer Prevention Research, Nov 12-15, 2006]