Preoperative Diagnostics of Papillary Thyroid Carcinoma by Molecular Analysis of FNAB Materials

Abstract

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer. Molecular markers of papillary thyroid carcinoma (PTC) including the BRAFT1799A mutation, RET/PTC1,3 rearrangements, and differentially expressed SFTPB (up-regulated) and TFF3 (down-regulated) genes were prospectively assessed in FNAB (fine needle aspiration biopsy) material from thyroid nodules.

We examined 73 cases, of them 59 PTC (papillary thyroid carcinoma), five nodular goiters, and nine follicular adenomas.

Concordantly with cytology, molecular diagnosis of PTC by SFTPB and TFF3 expression levels was confirmed in 38/41 cases (92.7%); in them, 22/41 (53.6%) had BRAFT1799A mutation and 7/41 (17.1%) had RET/PTC rearrangements. For benign nodules, concordance was observed in 10/12 (83.3%) cases. Among 20 cases, including 19 suspicious for malignancy and one inadequate sample, 17 were positive for SFTPB/TFF3 test (85.0%). Of these, four were also positive for RET/PTC rearrangements, five were positive for BRAFT1799A and all resulted in PTC at histology. The remaining 3 cases were negative for three molecular markers. These nodules showed benign lesions in histology.

Our results demonstrated that specific molecular tests improve the efficacy of preoperative diagnostics of PTC.