Association between nonspecific chronic lymphocytic thyroiditis and differentiated epithelial thyroid carcinoma: Clinicopathological analysis of patients who underwent thyroidectomy in a tertiary care center in Sri Lanka

Abstract

Introduction: The most common differentiated malignant thyroid neoplasm is papillary carcinoma. The association of concurrent presence of chronic lymphocytic thyroiditis and its subtypes with differentiated epithelial thyroid carcinoma remains controversial. Objective: To evaluate the epidemiological factors of chronic lymphocytic thyroiditis and association between chronic lymphocytic thyroiditis and its subtypes with differentiated epithelial thyroid carcinoma. Materials and methods: The histopathological records of 684 patients who underwent thyroidectomy at Teaching Hospital Kandy, Sri Lanka, for a period of 2½ years from January 2013 were reviewed. Their clinical and pathological characteristics were analyzed. Chronic lymphocytic thyroiditis was diagnosed by histology. Results: Thyroid malignancies were detected in 14.2% of thyroidectomy specimen, of which well-differentiated epithelial thyroid carcinoma was seen in 82%. Chronic lymphocytic thyroiditis was present in 31%, out of which 73.1% were nonspecific chronic lymphocytic thyroiditis and 26.9% were Hashimoto’s thyroiditis. Gender, age, and presence of thyroiditis were significantly associated with papillary thyroid carcinoma. In the analyzed sample, males were more likely to have papillary carcinoma compared with females (p = 0.013). Those with nonspecific chronic lymphocytic thyroiditis were more likely to have papillary thyroid carcinoma (p = 0.002) compared with those without. With increasing age, the proportion of lymphovascular invasion in patients with papillary thyroid carcinoma significantly (p = 0.010) decreases. None of the three factors mentioned were significant predictors of presence of follicular carcinoma, tumor focality, capsular or lymphovascular invasion in papillary or follicular carcinoma. Conclusion: The presence of nonspecific chronic lymphocytic thyroiditis is associated with papillary thyroid carcinoma at a given age and gender. Influence of nonspecific chronic lymphocytic thyroiditis on the prognosis of well-differentiated epithelial thyroid carcinoma needs to be investigated further with a larger sample size.