Studio osservazionale prospettico sull’outcome clinico dei pazienti affetti da carcinoma della tiroide

Aim: To identify clinical and molecular prognostic factors in differentiated thyroid cancer (DTC) Methods: A web based longitudinal database of newly diagnosed DTC was settled down. The risk of recurrence and the response to treatment were classified according to the American Thyroid Association (ATA) guidelines. Circulating miR analysis of sera collected before surgery and about 1 months and 1-2 years after surgery was performed with TaqMan MicroRNA Assay. Results: 2730 patients had a follow-up ≥1 year. The ATA risk of recurrence was low in 1386 (50.8%), intermediate in 1168 (42.8%) and high in 176 (6.4%). The response to treatment was excellent in 1675 (61.3%), biochemical incomplete in 63 (2.3%), structural incomplete in 70 (2.6%), and indeterminate in 922 (33.8%). A significantly higher rate of structural disease was found in intermediate (2.7%, Odds ratio 4.85, 95% confidence interval 2.18 - 12.23, p<0.01) and high risk (17.1% Odds ratio 35.21, 95% confidence interval 15.41 - 90.66, p<0.01) patients compared with low risk patients (0.6%). Of the 829 patients that had a follow up of ≥3 years, only 3 (0.6%) intermediate risk patients experienced relapse. Serum samples of 44 patients with papillary thyroid cancer (PTC) were available for miR profiling. After a screening analysis, miR-146a-5p and miR-221-3p were selected for validation because of superior accuracy in PTC identification from healthy controls and benign thyroid nodules. The trend over time of miR-146a-5p and miR-221-3p was decreasing in patients with disease remission and increasing in patients with structural disease. In 3 cases miR profile was more informative than the serum thyroglobulin. Conclusion: The ATA risk stratification is an effective clinical prognostic tool for structural disease prediction in DTC. One third of the patients has an indeterminate response to treatment due to low detectable serum markers (thyroglobulin or anti thyroglobulin antibodies). miR profile may represents a promising alternative marker of disease status for these patients.