Comparative study on association between serum TSH concentration and Thyroid cancer

Abstract

Background: In India, thyroid cancer accounts for less than 1% of all malignancies (2% of women and 0.5% of men). Thyroid cancer is responsible for 6 deaths per 1 million persons annually. Serum TSH is a well-established growth factor for thyroid nodules, however its role in thyroid malignancy is inconclusive hence this study was conducted with the objective to determine the association between serum Thyroid stimulating hormone (TSH) concentrations with thyroid carcinoma. Methods: Case control study was conducted in a tertiary care centre. 120 Benign and malignant thyroid subjects respectively were included in the study. Newly diagnosed and record based data collection was done. Measurements of serum TSH concentrations were performed by automated immune chemiluminescent assay. Data was analyzed using SPSS 22 version software, Chi-square test was used as test of significance for qualitative data, p value of <0.05 was considered as statistically significant. Results: Majority of them were females in the age group 26 to 40 years in both the groups and were diagnosed to have solitary thyroid nodule. In malignant thyroid nodules 51.7% were diagnosed to have follicular carcinoma, 46.7% had papillary carcinoma and 1.7% were diagnosed to have Hurthle cell carcinoma. Significant association was observed between TSH levels and diagnosis of thyroid lesions. TSH was raised (>4mIU/L) in 46.6% of malignant nodules and in 15% of benign nodules. Raised TSH had an odds ratio of 4.958 for Thyroid malignancy compared to benign nodules Conclusions: Higher TSH levels were associated with Thyroid malignancy and the risk of malignancy rises in parallel with serum TSH within normal range, and high levels of serum TSH concentrations was associated with advanced stage of thyroid cancer.