Although there was no statistically significant difference in terms of MGMT, MSH2, MLH1 immunoreactivity values, as seen in Table 4, there was no difference in immunoreactivity between papillary carcinoma cases and chronic thyroiditis cases, but the difference between papillary carcinoma and colloidal goiter was more pronounced in favor of papillary carcinoma. The gene discussed is MLH1; the disease is thyroid gland papillary carcinoma.