EXPRESSION OF THE RET PTC FUSION GENE AS A MARKER FOR PAPILLARY CARCINOMA IN HASHIMOTOS-THYROIDITIS/

Hashimoto's thyroiditis is an inflammatory disease of the thyroid glan d with autoimmune etiology.(1) Patients afflicted with Hashimoto's hav e a higher risk of thyroid malignancies such as papillary thyroid carc inoma.(2) In the present study, we investigated the frequency of papil lary thyroid carcinoma specific genes in patients diagnosed with Hashi moto's disease. The newly identified oncogenes RET/PTC1 and RET/PTC3 p rovide useful and specific markers of the early stages of papillary ca rcinoma as they are highly specific for malignant cells. Using a sensi tive and specific reverse transcriptase-polymerase chain reaction (RT- PCR) assay, we found messenger RNA (mRNA) expression for the RET/PTC1 and RET/PTC3 oncogenes in 95% of the Hashimoto's patients studied. All Hashimoto's patients presenting without histopathologic evidence of p apillary thyroid cancer showed molecular genetic evidence of cancer. T hese data suggest that multiple, independent occult tumors exist in th ese patients at high frequency.