Correlation between Histopathology of Solitary Thyroid Nodule and Thyrotropin Thyroglobulin Ratio.

Background; Differentiated thyroid cancers (DTC) are becoming more common, along with thyroid disorders. Palpable thyroid nodules are seen in the patient population at a rate of 5% in female patients and 1% in male patients. Aging is associated with an increased incidence of thyroid nodules. Owing to advances in technology and the accessibility of medical facilities, the incidence of incident thyroid nodules has increased to as high as 19% to 68%. Aim of the work; Detection of diagnostic accuracy of thyrotropin to thyroglobulin ratio in comparison with post-operative pathology to differentiate between benign and malignant solitary thyroid nodule. patients and methods; This prospective study was conducted on 50 patients presented with solitary thyroid nodule to the general surgery and endocrine surgery outpatient clinics at Mansoura university hospitals. They were chosen according to inclusion and exclusion criteria. Thyrotropin and thyroglobulin levels were estimated for all patients, ratio between them was calculated, and then this ratio was compared with final post-operative pathology to detect the diagnostic accuracy of this ratio in differentiation between benign and malignant nodule.Result; The final pathology showed that 41 (82%) of the studied patients had benign nodules and 9 (18%) had malignant nodules. Using of thyrotropin thyroglobulin ratio cut of value 25.94, we find that 40 patients proved to be benign from total 41 benign patients and 8 patients proved to be malignant from total 9 malignant patients. Area under the curve for thyrotropin thyroglobulin ratio is excellent (AUC = 0.97) with the best detected cut off point is 25.94 yielding sensitivity 88.9% and specificity 97.6% with total accuracy 96% Conclusion; from the study it is shown that thyrotropin thyroglobulin ratio is of great significance in differentiation between benign and malignant solitary thyroid nodule with best cut off point is 25.94.