For FNA specimens of 57 thyroid tumors followed-up for more than 10 years postoperatively and stained with both the Papanicolaou and the immunoperoxidase technique using MoAb JT-95, we retrospectively compared the sensitivity, specificity, and diagnostic accuracy of the two procedures. Histological specimens stained with HE and investigated by JT-95 were also re-evaluated. The pathological results of aspirated specimens, after a change in diagnosis following recurrence, revealed that 43 of 47 malignant lesions were positive, while nine of 10 benign tumors remained unreactive using MoAb JT-95.
Sensitivity was 91.4 % , specificity 90.0 % , and diagnostic accuracy 91.2 % by JT-95 cytology. By contrast, sensitivity ascertained by the Papanicolaou technique was 78.1 % , specificity 100 % , and accuracy 82.4 % . Of the six examples that recurred during the 10–12-year follow-up period, tissue sections of all six and aspirated materials of five of the six were stained by JT-95.