Galectin-3 immunostaining in cytological and histopathological diagnosis of thyroid lesions

الملخص EN

Background: Galectin-3 is a human lectin linked to malignant transformation in different organs including thyroid gland.

We aimed to evaluate the diagnostic role of galectin-3 in differentiating benign from malignant thyroid lesions in cytological and histological samples.

Material and Methods: This study included a total of 79 cases; 19 multinodular goiter (MNG), 19 follicular adenoma (FA), 13 follicular carcinoma (FTC) and 28 papillary carcinoma (PTC).

Galectin-3 immunostaining was applied on histological sections from all the cases (retrospective analysis) as well as for the available preoperative FNAC (28 cases) (prospective analysis).

Results: Retrospective analysis: The positivity percentage of galectin-3 was 10.5%, 92.3%, 93% for nonmalignant, FTC and PTC respectively.

According to H score, glaectin-3 immunostaining was significantly lowered in FA) 1±2.8 as compared to papillary (158.5±88.6) and follicular carcinoma (150±83.9) (p>0.0001).

However, there was no statistically significant difference between FTC and PTC (p=0.56) or between classic and follicular variants of PTC (p=0.51).

Sensitivity, specificity, positive and negative predictive values for galectin-3 staining were 93%, 89.5%, 90.5% and 92% respectively.

Prospective analysis: There were five benign, six malignant and 17 indeterminate cytology cases.

Galectin-3 immunostaining was able to detect the benign nature of 11/17 indeterminate cytology.

Combination of standard cytological evaluation with galectin-3 immunostaining markedly improved sensitivity (71% versus 85%), specificity (75% versus 94%), positive predictive value (83% versus 92%) negative predictive value (60% versus 87.5%) and diagnostic accuracy (72% versus 90%).

Conclusion: We suggest Galectin-3 as a supplementary immunostaining in histological diagnosis of difficult thyroid follicular lesions and in preoperative evaluation Journal of the Egyptian Nat.

Cancer Inst., Vol.

20, No.

1, March: 36-46, 2008 Galectin-3 Immunostaining in Cytological and Histopathological Diagnosis of Thyroid Lesions HAYAM A.

AIAD, M.D.*; MONA A.

KANDIL, M.D.*; NANCY Y.

ASAAD, M.D.*; AHMAD M.

EL-KASED, M.D.** and SHEREN F.

EL-GODAY, MS.c.* The Departments of Pathology* and General Surgery**, Faculty of Medicine, Menoufiya University.

36 of indeterminate thyroid cytology to avoid unnecessary aggressive surgical interference in benign lesions.