The role of CD56, HBME-1, and CK19 immunohistochemical markers in the differential diagnosing of thyroid neoplasms

Abstract

Background: The diagnosis of thyroid neoplasms is steadily increasing due to the widespread use of sensitive
diagnostic techniques. While histopathologic evaluation using Hematoxylin and Eosin (H&E) staining is
considered the "gold standard," it often faces challenges due to morphological overlap between benign and
malignant follicular patterned lesions. This led to diagnostic uncertainties, underscoring the need for
Immunohistochemistry (IHC) as a valuable adjunct. This study aims to evaluate the expression of IHC markers,
Hector Battifora Mesothelial Cell-1 (HBME-1), Cluster of Differentiate (CD56 also known as Neural Cell
Adhesion Molecule) and Cytokeratin-19 (CK19), in follicular patterned neoplasms of the thyroid to aid in the
diagnosis of malignant thyroid neoplasms
Methodology: The study was a descriptive analysis and it included 60 thyroidectomy specimens diagnosed as
neoplastic by histopathology were studied after satisfying the inclusion and exclusion criteria. The IHC results
were interpreted semi-quantitatively. Statistical analysis was performed using Chi-square test and Fisher’s-exact
tests. A P-value of <0.05 was considered as significant. Sensitivity and specificity for each marker and their
combination in diagnosis were calculated.
Results: Among the sixty cases, 31.67% were benign neoplasms, and 68.33% were malignant. Loss of CD56
expression was noted in 75.68% of malignant cases. The specificity of CD56, HBME-1, and CK19 in identifying
malignant neoplasms was 84.21%, 84.21%, and 89.47%, respectively. The accuracy of CD56 and CK19 in
diagnosing follicular variant papillary thyroid carcinoma (FVPTC) from follicular adenoma (FA) was 79.31% and
93.10%, respectively. The specificity of CK19 in distinguishing FVPTC from FA was 89.47%. The specificity of
CD56, CK19, and HBME-1 in diagnosing follicular thyroid carcinoma (FTC) from FA was 84.21%, 85%, and
84.21%, respectively.
Conclusions: Our study highlights the diagnostic utility of CD56, CK19, and HBME-1 in thyroid neoplasms
incorporating these markers into routine diagnostic panels can significantly enhance the accuracy and reliability of
thyroid malignancy assessments.