Both the follicular thyroid carcinoma (FTC) and the metastasis were investigated for the presence of <i>BRAF/RAS</i> and <i>TERT</i> promoter mutations.
To our knowledge, this is the first reported case of synchronous and metastatic primary papillary and follicular carcinomas, and the first report of synchronous BRAFV600E mutated papillary and NRAS mutated follicular carcinoma.
Twenty-seven out of 29 nodules (93%) with BRAF(K601E) mutated tumors with surgical pathology results available for review were PTC, one (3.4%) was a follicular thyroid carcinoma, and one (3.4%) was a follicular adenoma.
In this large cohort, we found TERT promoter mutations to be common, particularly in FTC and BRAF mutation-positive PTC, and associated with aggressive clinicopathological characteristics.
For example, the analysis of BRAF, RAS and other mutations in cytological samples may help to distinction between follicular thyroid carcinoma and follicular thyroid adenoma and may significantly decrease the number of unnecessary surgery among patients with thyroid nodules.
Although BRAF mutations are detected exclusively in papillary carcinoma, they are also found in medullary carcinoma and follicular carcinoma.[Corrected]
Non-overlapping genetic alterations, including BRAF and RAS point mutations, and RET/PTC and PAX8/PPARγ rearrangements, are found in more than 70% of papillary and follicular thyroid carcinomas.
It was significantly associated with extrathyroidal and vascular invasion of FVPTC and FTC and, remarkably, a 50%-60% rate of multifocality and recurrence of BRAF mutation-positive PTC (P = 0.01 and 0.02, respectively).
Here we review this topic and illustrate major features by presenting multimodal management of a patient with BRAF-positive disseminated follicular thyroid cancer arising in an ovarian teratoma.
Most of these genetic alterations are particularly common in FTC and many of them are even more common in ATC; they are generally less common in papillary thyroid cancer (PTC), in which the MAP kinase (MAPK) pathway activated by the BRAF mutation instead plays a major role.
: The prevalence of BRAFV600E mutation was higher in conventional papillary thyroid cancer (51.0%) than in follicular variant of papillary thyroid cancer (24.1%) and follicular thyroid cancer (1.4%) (P < 0.0001).
The purpose of this study was to test this notion by examining whether and, if so, how often ATC harbors the oncogenes that are commonly associated with WDC, such as RAS in FTC and BRAF in PTC.
In an attempt to clarify such controversies and to find whether or not FVPTC cases share the molecular features of follicular tumors, we searched for the presence of PAX8-PPARgamma rearrangements, RAS mutations, and RAP-1, RAF-1, and BRAF mutations in a series of 40 FVPTCs as well as in 27 follicular thyroid carcinomas (FTCs) and 12 follicular thyroid adenomas (FTAs).
In 137 specimens of FNAB (107 papillary thyroid carcinomas (PTC); 3 follicular thyroid carcinomas (FTC); 2 undifferentiated thyroid carcinomas; 25 benign lesions), both direct DNA sequencing and PCR-RFLP were used for detecting the BRAF(V600E) mutation.
The absence of BRAF mutations in our series of PDC supports the assumption that pure insular and insular-like PDCs are more closely related to follicular carcinoma than to PTC.