To evaluate BRAF(V600E) mutation on consecutive fine-needle aspiration biopsy (FNAB) specimens in order to assess FNAB's usefulness in preoperative papillary thyroid carcinoma (PTC) diagnosis with the contemporaneous analysis of RET/PTC1 and RET/PTC3 rearrangements obtained from ex vivo thyroid nodules.
Seventeen patients underwent a thyroid nodule FNAB (results: 12 benign, one follicular neoplasm, three suspicious for malignancy, and one papillary thyroid cancer [PTC]), from which six underwent thyroidectomy; PTC was confirmed by surgical pathology for all cases (8.5% of all nodules observed).
In thyroid nodule fine-needle aspiration (FNA) cytology, the atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) category has a 5-15% malignancy risk that increases to 85-99% when mutation testing for BRAF, RAS, RET/PTC, or PAX8/PPARγ is positive.
In this study, we performed the molecular analysis using a new simplified procedure that involves a panel of BRAF, RAS, RET and RET/PTC gene mutations in easily obtainable FNA samples, in the attempt to improve the efficacy of the FNA diagnosis of thyroid nodules and thus patient management.
Detection of RET/PTC, TRK and BRAF(V600E) in FNAB specimens is proposed as a diagnostic adjunctive tool in the evaluation of thyroid nodules with suspicious cytological findings.
A molecular profile including BRAF and RAS mutations as well as RET/PTC rearrangement evaluation has been proposed to provide an accurate presurgical assessment of thyroid nodules and to reduce the number of unnecessary diagnostic surgeries, sparing patients' health and saving healthcare resources.
Assessment of RET/PTC oncogene activation and clonality in thyroid nodules with incomplete morphological evidence of papillary carcinoma: a search for the early precursors of papillary cancer.
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.