Diagnostic value of galectin‐3 as a marker for malignancy in follicular patterned thyroid lesions

BACKGROUND: The determination of malignancy in follicular patterned thyroid lesions is based on postoperative histologic findings. Therefore, affected patients are referred for surgery, although only 20% will have a final diagnosis of malignancy. The aim of this study was to investigate the potential of galectin-3 as a marker of malignancy in these lesions. METHODS: Fifty-four tissue specimens of follicular patterned thyroid lesions were immunohistochemically stained for galectin-3. Area and intensity scores were recorded. RESULTS: Significant differences were found between the benign and malignant lesions. The sensitivity, specificity, positive predictive values, and negative predictive values of galectin-3 staining were 82%, 68%, 75%, and 77%, respectively (p=.0002). Significant differences were also found between the subgroups of benign and malignant lesions (p < or =.05). CONCLUSIONS: Galectin-3 staining is highly sensitive for malignancy in follicular patterned thyroid lesions. Diagnostic problems may arise in the presence of Hurthle cell proliferation or minimally invasive follicular carcinoma.