In accordance with our previous reports, we found that observation of concomitant CD26-positive and PTEN-negative status in cases of follicular adenoma suggests a state close to follicular carcinoma or progression to cancer, thus warranting careful follow-up.
RT-PCR analysis demonstrated overexpression of galectin-3 and CD26/DPPIV mRNAs in all six papillary and all three follicular carcinomas analyzed, whereas the mRNA expressions of these molecules were barely or not detectable in benign thyroid lesions and normal thyroid tissues, except for one case of follicular adenoma.