Rationale for Testing TP53 Mutations in Thyroid Cancer—Original Data and Meta-Analysis

The p53 protein is a tumor-suppressing transcription factor that is critical in tumorigenesis. While TP53 mutations are rare in differentiated thyroid cancer (DTC), they are significantly more common in anaplastic thyroid cancer (ATC). This study presents original results and a meta-analysis reevaluating the prognostic value of TP53 mutations in thyroid cancer, including surrogate markers such as immunohistochemical p53 expression and serum p53-Abs levels. TP53 mutations were analyzed using SSSP and direct sequencing in a DTC group (15 patients), an ATC group (3 patients), and a control group (25 patients). The immunohistochemical p53 expression was assessed in tissue samples. A meta-analysis of 14 eligible studies identified through the PubMed, Scopus, Google Scholar, and Cochrane databases was conducted. Our results showed TP53 mutations in all ATC cases, 6.67% of DTC cases (1 out of 15), and none in the control group. Immunohistochemical p53 overexpression was observed in 4 out of 15 DTC (26.67%) and all ATC cases but absent in controls. A meta-analysis confirmed that TP53 mutations are significantly more frequent in ATC than controls (OR 8.95; 95% CI: 1.36–58.70; p = 0.02) but not in DTC vs. controls (OR 1.87; 95% CI: 0.53–6.58; p = 0.33). p53 overexpression was significantly higher in both DTC and ATC vs. controls (OR 7.99; 95% CI: 5.11–12.51; p < 0.01 and OR 64.37; 95% CI: 27.28–151.89; p < 0.01, respectively). The serum p53-Abs positivity was also elevated in patients with PTC vs. controls (OR 2.07; 95% CI: 1.24–3.47; p < 0.01). TP53 mutations are frequent events in the pathogenesis of ATC. In DTC, further prospective studies are needed to determine the prognostic value of TP53 mutations and related surrogate markers (immunohistochemical p53 expression, p53-Abs positivity).