The expression of sialic fibronectin correlates with lymph node metastasis of thyroid malignant neoplasmas.

BACKGROUND Papillary thyroid carcinoma (PTC) is often accompanied by lymph node metastasis (LNM), compared with follicular thyroid carcinoma (FTC). Sialic acid is carried by fibronectin (sFN) as the antigen of monoclonal antibody (MoAb) JT-95 detected in 90% of PTC, and a few cases of FTC. PATIENTS AND METHODS JT-95 staining was performed in 9 PTC and 20 follicular type tumors to investigate the relationship between the expression of sFN and the frequency of LNM. RESULTS There were 11 cases with LNM from 23 malignant tumors, and no cases of LNM from 6 benign follicular type tumors. The staining scores by JT-95 of the 11 tumors with LNM were 5+ in 4 cases, and 6+ in 7 cases. On the other hand, the scores of 12 malignant tumors without LNM were <4+ in all cases. CONCLUSION An increase of sFN expression in thyroid malignancies is correlated with LNM.