EVALUATION OF THE DIAGNOSIS USEFULNESS OF OC125 IMMUNOSCINTIGRAPHY FOR OVARIAN CARCINOMAS FOLLOW-UP AFTER TREATMENT - CONTRIBUTION OF THIS TECHNIQUE IN THE CHU OF GRENOBLE

Immunoscintigraphy using indium-111-labeled OC125 monoclonal antibody F(ab')2 fragments is a technic complementary of morphological imaging (i.e. ultrasonography and computed tomography). It allows early detect ion of recurrences of ovarian carcinomas. We performed immunoscintigra phy 30 times in 26 patients who previously underwent radical treatment for ovarian carcinoma, and were suspected to have a recurrence. Our p urposes were appreciation of diagnostic accuracy of the method, and ab ove all its impact on clinical decisions and evolution of the patients . There were, after reevaluation of the results, 18 true positives, 7 true negatives, 3 false negatives and 2 false positive cases (sensitiv ity 85.7%, specificity 77.8%). Bayesian analysis showed positive and n egative predictive values of 86% and 87% when probability of recurrenc e a priori was 50%, and 80% and 58% when probability of recurrence a p riori was 70%. The result of immunoscintigraphy contributed to clinica l decisions in 24 cases out of 30, and led to a correct decision for t he patient in 21 cases. Conversely, for the 6 cases in which the resul t has not been considered, to take this result into account would have been beneficial in 4 cases, but harmful in 2. Finally, survival tende d to be longer when immunoscintigraphy was negative, which could be as sociated with a better prognosis. We conclude that OC125-immunoscintig raphy may be useful for ovarian carcinoma follow-up and may contribute to a better therapeutic strategy.