Abstract

BACKGROUND
Fine needle aspiration, which is known as the most accurate and cost-effective method for diagnosis of thyroid nodule, still may result in indeterminate cases that are pauci-cellular and show minor nuclear atypia, but most cases are associated with suspicion of papillary thyroid carcinoma (PTC). A B-type Raf kinase (BRAF) mutation was found in about half of PTCs and galectin-3 was expressed by malignant tumors, helping us to differentiate malignancies from benign lesions.
METHODS
Cases studied included histologically 44 confirmed PTC cases and 18 benign cases previously diagnosed as suspicious of PTC using cytologic examination. Cases were analyzed for galectin-3 expression by immunohistochemical staining and BRAF mutation by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) with a new restriction enzyme.
RESULTS
All 44 cases of PTC and 8 of 18 benign controls expressed galectin-3. BRAF mutations were found in only 9 of the 44 PTC cases. Assessment of galectin-3 expression demonstrated high sensitivity but low specificity. Evaluation of BRAF mutation revealed high specificity and low sensitivity.
CONCLUSIONS
This study suggests that the combined application of these two methods for PTC of suspicious cytology is complementary.

• Keywords: Suspicious cytology;Biopsy, fine needle;BRAF mutation;Galectin-3;