ACCURATE AND OBJECTIVE PREOPERATIVE DIAGNOSIS OF THYROID PAPILLARY CARCINOMAS BY REVERSE TRANSCRIPTION PCR DETECTION OF ONCOFETAL FIBRONECTIN MESSENGER-RNA IN FINE-NEEDLE ASPIRATION BIOPSIES

Recently, the restricted expression of oncofetal fibronectin mRNA was reported in thyroid papillary and anaplastic carcinomas. In this study , by extracting RNA from the leftover cells inside the needles used fo r fine-needle aspiration biopsy, we establish a new method for gene di agnosis of these carcinomas without further invasiveness to the patien t (aspiration biopsy-reverse transcription-PCR, ABRP). RNA was extract ed from 177 fine-needle aspiration biopsies of thyroid nodules that we re suspicious for malignancy, and then the gene diagnoses made by reve rse transciption-PCR detection of oncofetal fibronectin mRNA were comp ared with cytological diagnoses. Thirty-five (94.6%) of 37 samples tha t were diagnosed as papillary or anaplastic carcinomas by cytological examination showed a positive result by gene diagnosis, whereas only 4 (3.7%) of 109 samples that were cytologically diagnosed negative for both carcinomas showed a positive result. Among all of the cases, 50 p atients underwent surgery, and a histological diagnosis was consequent ly made. The sensitivity and specificity of this method were 96.9 and 100%, respectively. A combined examination using both genetic and cyto logical approaches may contribute to a more precise preoperative diagn osis of papillary and anaplastic carcinomas.