[Expression of cytokeratin19, galectin-3 and HBME-1 in thyroid lesions and their differential diagnoses]

To study immunohistochemical expression of cytokeratin19 (CK19), galectin-3 (Gal-3) and HBME-1 in thyroid lesions and to assess their usefulness as markers in the differential diagnoses of thyroid nodular lesions.

Immunohistochemical staining was performed on formalin-fixed paraffin-embedded tissue of 21 cases of nodular goiters, 14 cases of toxic goiters, 15 cases of follicular adenomas (FA), 13 cases of follicular carcinomas (FC), 13 cases of follicular variant papillary carcinomas (FVPC) and 48 cases of classic papillary carcinomas (CPC).

All three markers were expressed in the cytoplasm with no or weak expression in benign lesions and diffuse and strong in malignant cases. Positive expressions of CK19, Gal-3 and HBME-1 were present in 11of 21, two of 21, four of 21 in nodular goiters, seven of 14, one of 14, one of 14 in toxic goiters, nine of 15, two of 15, two of 15 in FA, 10 of 13, eight of 13, seven of 13 in FC, 13 of 13, 11 of 13, 12 of 13 in FVPC, and 48 of 48, 45 of 48, 46 of 48 in CPC. The expression rates of the three markers between benign lesions (nodular goiters, toxic goiters and FA) and malignant lesions (FA, FVPC and CPC) were statistically significant. Among the three follicular lesions (FA, FC and FVPC), the differences were statistically significant as well. Nine, seven and six cases were negative for all three markers in nodular goiters, toxic goiters and FA, respectively. Only one case in FC was negative for all three markers, no case was all negative in FVPC and CPC; the rate of one case with two or more positive marker expression in nodular goiters, toxic goiters, FA, FC, FVPC and PC was 14.2% (3/21), 21.43% (3/14), 20.0% (3/15), 69.2% (9/13), 92.3% (12/13), 100.0% (48/48), the differences between benign lesions and malignant lesions and between FA, FC and FVPC were also statistically significant.

Immunohistochemical stains of CK19, Gal-3 and HBME-1, especially when used in combination, can be an important adjunct to the histopathological diagnoses of thyroid lesions.