MALIGNANCY MARKERS IN THE CYTOLOGICAL DIA GNOSIS OF THYROID-NODULES -THYROID PEROXIDASE

The enzyme thyroid-peroxidase (TPO) possesses in thyroid malignancy an immunological alteration disclosed by an anti-TPO monoclonal antibody termed MoAb47: a negative immunostaining with MoAb47 thus represent a marker of malignancy for thyroid tumors. The present work has been in tended to investigate the ability of TPO immunodetection to assist the diagnosis of malignancy in Sine-needle aspirates (FNA) of thyroid nod ules. The study concerns 300 patients with histologically proven thyro id nodules. The results of TPO immunodetection have been compared to t he final histological diagnosis and in 279 cases, to the results of st andard cytological analysis. From 248 benign nodules, 215 yielded move than 80 % positive cells. All malignant nodules had less than 80 % po sitive cells and most of them less than 40 %. According to these resul ts, with 80 % positive cells as the threshold between benign and suspi cious or malignant results, the sensitivity of the method for the scre ening of malignancy is 100 %, its specificity, 86,7 % and its overall accuracy 89 %.