Sonographic evaluation of solitary thyroid nodule with cytopathological correlation

Abstract

Background: Nodular thyroid disease is a common health problem affecting women affected more frequently than men. Benign conditions like simple thyroid cyst, iodine deficiency disorder, chronic inflammatory disease of thyroid (like Hashimoto?s thyroiditis) as well as malignancy of different grades (ranging from well differentiated papillary carcinoma to high grade follicular neoplasm) can present with thyroid nodules. Differentiation between two entities based on clinical and biochemical ground alone is hardly possible and here comes the role of high resolution ultrasonography. Because of superficial location USG can identify normal thyroid anatomy and pathologic conditions with remarkable clarity. Based on sonologic features it is possible to predict whether a nodule is malignant or not and hence whether follow-up is sufficient or more invasive procedure is imperative. Materials & Methods: Fifty sequential adult patients of 15-60years of age presenting with nodular thyroid disease were studied over the period of one and half years (January 2016 to June 2017). Specific USG criteria were used to characterize the nodules so that a probable diagnosis could be made. Sonological diagnoses then compared with cytological results to conclude role of USG to analyse nodular thyroid disease. Result & Analysis: 50 patients were studied with a mean age of 37.4 years. Benign lesions constitute the majority (total 43 cases) four patients were diagnosed as having papillary carcinoma & three as case of follicular neoplasm. Most of the patients presented with long standing painless palpable thyroid swelling. Majority of malignant thyroid nodules presented as solitary hypoechoic solid nodules with intranodular vascularity. On contrary benign lesions were mainly iso or hyper echoic, multiple or solitary, well margined nodules with perinodular vascularity. Cervical lymphadenopathy & micro calcification were found almost exclusively in papillary carcinoma, whereas peripheral egg shell calcification &comet tail artifacts were seen only in hyperplastic nodules. Conclusion: Nodular thyroid disease was found to be of female predominance with benign causes outnumbered malignancy. USG assessment helped assess characteristics of thyroid nodules to reach a provisional diagnosis. We had taken into account parameters and among them taller than wide shape, intranodular vascularity with or with-out perinodular component and marked hypoechogenicity emerged as most useful.