European Journal of Molecular & Clinical Medicine

Background: Papillary thyroid carcinoma is the commonest malignancy of thyroid. The diagnosis of such lesions can be easily rendered by using standard histological criteria. However, distinguishing the follicular variant of papillary carcinomafrom other follicular neoplasmsis difficult. Objectives:  In this study we investigated the role of CD56, CK19 and p63 in differentiating papillary carcinoma thyroid from follicular neoplasms.
Materials and Methods: The immunohistochemical expression of CD56, CK19 and p63 was evaluated individually and in combinations in 30 samples of thyroid lesions. Thyroid lesions included: 26 Papillary carcinoma thyroid [classic papillary carcinoma (21) and follicular variant of papillary carcinoma thyroid (5)] and 4 cases of follicular carcinoma.
Results: CD56 was found to be 100% sensitive and 84.62% specific in differentiating papillary thyroid carcinoma from follicular neoplasms. p63 was 50% sensitive and 57.69% specific in differentiating papillary thyroid carcinoma from follicular carcinoma.CD56 and CK19 were more specific than p63 in differentiation of Papillary carcinoma thyroid from follicular neoplasms. (p=0.039,0.001 respectively).Combination of all the three markers showed sensitivity and specificity of  100% and 53.85% respectively.
Conclusion: Combined utility of CD56, CK19 and p63 is helpful in diagnosing papillary thyroid carcinoma including follicular variant and it’s differentiation from follicular carcinoma.