More than 95% of thyroid gland malignancies are well-differentiated tumors.
Preoperative diagnosis accuracy for papillary carcinomas, based on FNAC (Fine
Needle Aspiration Cytology) and ultrasound screenings, has become nearly 100%.
Nevertheless, when follicular neoplasm diagnosis is concerned, this reality is quite
different. Using current preoperative screening tools, 60 – 80% of patients suspected
to present follicular thyroid cancer, when operated turn out to suffer from benign
disease. Therefore, in an effort to improve these results, genomic analysis of Copy
Number Variations (CNV) that may more precisely differentiate follicular tumor from
other thyroid conditions were carried out in 13 patients (3 bearing goiters, 2
hyperplasias, 4 follicular adenomas, 4 follicular carcinomas, 1 healthy individual).
CNVs were tracked through aCGH method in order to detect follicular carcinoma
most accurately. Results were compared with classic papillary carcinoma (4 subjects)
and follicular variant (2 subjects). Samples demonstrated 725 CNVs, 703 of which
belonging to patients with disease. Among these, 18 most frequent regions were
selected. Patterns of amplification were more frequent in younger patients, while
deletions were more frequent in the elder ones. Carcinoma patients presented very
close CNV rates. Also, exclusive patterns of chromosomes 8 and 12 alterations were
noticed in follicular carcinoma. Thus, it is possible to conclude that thyroid follicular
carcinoma is a condition comprehending exclusive patterns of alterations, and
progression of this disease is not related to follicular adenomas. Finally, regions -8p22
and 12p13.32-p12.33 were detected in 100% and 75% of samples respectively,
therefore, may be deemed as possible tumoral markers.
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