By the higher sensitive Southern-blot on RT-PCR method, RET rearrangements were present in 36% of papillary thyroid carcinomas (RET/PTC-1, 12%.     ///    Prevalence of RET/PTC rearrangement in benign and malignant thyroid nodules and its clinical application..     ///    "These results indicate that molecular testing of thyroid nodules for RET/PTC must take into account of its high prevalence in benign nodules, inducing false positive diagnoses when the highly sensitive assay Southern-blot on RT-PCR is used. "    ///    "RET/PTC-3, 20%. "