Utility of immunohistochemical markers in diagnosis of follicular cell derived thyroid lesions.

Differentiating the follicular derived lesions can be challenging. Although immunohistochemistry is generally accepted as a useful ancillary technique in the diagnosis, controversy exists regarding the best marker or combination of markers to distinguish each lesion from its mimics. In this study, we aimed at evaluating multiple markers to compare their sensitivity and usefulness, and to find out if a combination of the evaluated markers can be of additional value in discriminating thyroid lesions. The study included two groups of follicular derived thyroid lesions; benign group (Grave's disease, nodular goiter, Hashimoto's and adenoma) and malignant group (papillary, follicular carcinoma, well differentiated tumors of unknown malignant potential and follicular tumour of unknown malignant potential). Immunohistochemical evaluation of CD56, HBME-1, Gaectin-3 and CK19 were done. The sensitivity, specificity for each marker and their combination were calculated. Each marker was sensitive and specific for certain lesion but the sensitivity and specificity was increased when use combination of markers. Although no single marker is completely sensitive and specific for follicular thyroid lesions, the combination of CD56, HBME-1, Gaectin-3 and CK19 attains high sensitivity and specificity in diagnosis.