Histopathological Study of Thyroid Neoplastic Lesions in a Tertiary Care Hospital - A 5 Year Study

Introduction: Diseases of the thyroid gland are common and comprise a spectrum of entities causing systemic disease or a localized abnormality in the thyroid gland such as nodular enlargement or a tumor mass. Thyroid cancer is a relatively rare malignancy, but it is the commonest endocrine cancer accounting for 92% of all endocrine malignancies. The aim of this study was to describe the pattern of thyroid malignancies in thyroidectomy specimens. Material and Methods: This study was done in the Postgraduate Department of Pathology, Government Medical College, Srinagar and its associated hospitals over a period of five years from January 2013 to February 2018. The study was partly retrospective from Jan 2013 to July 2016 and partly prospective from August 2016 to Feb 2018. The thyroid diseases were classified on histological grounds into non-neoplastic and neoplastic lesions that were further subclassified as benign and malignant as per the WHO histological classification of thyroid tumors. Results: A total of 282 thyroid specimens were received during this study period. Neoplastic lesions were found in 204 cases (72.34%). 78.92% cases were females and 21.08% cases were males with a female: male ratio of 3.75:1. Out of 204 neoplastic lesions, 55 cases were benign accounting for 26.96% of neoplastic lesions. The age of the studied benign thyroid neoplastic lesions ranged from 9 years to 65 years with a mean age 38.11 years and the relative peak age of incidence was seen in 40-49 years age group (29.09%). Malignant thyroid lesions accounted for 72.55% (n=148) of all neoplastic lesions. The age of the studied malignant thyroid neoplastic lesions ranged from 9 years to 74 years with relative peak age of incidence between 20-29 years of age followed by 30-39 years age group. One case was diagnosed as well differentiated tumor of unknown malignant potential (WDTUMP). Papillary carcinoma was the commonest malignant tumor seen in 85.14% (n=126) of all malignant lesions. Follicular adenoma was most common benign neoplasm. Conclusion: Papillary carcinoma was the commonest malignant lesion while as follicular adenoma was the commonest benign adenoma.