Nucl Med Mol Imaging.  2006 Feb;40(1):9-15.

Comparison of Na+/I- Symporter Expression Rate in Malignant and Benign Thyroid Diseases: Immunohistochemical Study

• Kang DY
• Jeong YJ
• Lee KE
• Park HS
• Yoo YH
• Roh MS

Abstract

PURPOSE: Previous studies have not showed consistent results for the level of expression of sodium/iodide symporter (NIS) in thyroid diseases, especially malignant tumor. We undertook this study to evaluate the distribution of NIS expression in malignant thyroid diseases and compare with that in benign thyroid disease.
MATERIALS AND METHODS
Total patients were 119 cases (Men 15, 48+/-13 yrs). Total number of samples were 205 pieces. In malignant thyroid disease, there were 153 samples: 90 in papillary carcinoma, 4 in follicular carcinoma, 2 in medullary carcinoma and 57 in metastatic lymph node. In benign thyroid disease, there were 52 samples: 36 in goiter/cyst, 11 in thyroiditis and 5 in follicular adenoma. Using immunohistochemical methods, we probed 205 samples with monoclonal anti-NIS Ab. Grading of staining was scored as 0 (negative or absent), 1 (weakly positive), 2 (moderately positive) or 3 (strongly positive). Expression rate (ER) of NIS positivity in individual disease entity was expressed as percentage of total number divided by number in 2 plus 3 grade.
RESULTS
ERs of malignant thyroid diseases were 63% in papillary carcinoma, 81% in metastatic lymph node, 71% in follicular carcinoma and 100% in medullary carcinoma. ERs of benign thyroid disease were 53% in goiter/cyst, 64% in thyroiditis and 40% in follicular adenoma. ER of malignant thyroid diseases was higher than benign thyroid diseases (71% vs 54%). Grading of NIS expression in papillary carcinoma or goiter/cyst was heterogeneously distributed in considerable cases. Normal tissue also showed heterogeneous distribution of NIS expression, which was not correlated with that of primary lesion.
CONCLUSION
In papillary thyroid carcinoma, distribution of NIS expression was heterogeneous and increased, and not different compared with that of benign thyroid disease.

Keyword

sodium/iodide symporter(NIS); immunohistochemistry; thyroid carcinoma; benign thyroid disease

MeSH Terms

Adenoma
Carcinoma, Medullary
Carcinoma, Papillary
Humans
Immunohistochemistry
Ion Transport*
Lymph Nodes
Thyroid Diseases*
Thyroid Gland*
Thyroid Neoplasms
Thyroiditis