Diagnostic utility of galectin-3 in aspirates of thyroid follicular lesions.
OBJECTIVE
To investigate the expression of galectin-3 in various thyroid follicular lesions, including diffuse hyperplasia, nodular hyperplasia, and benign and malignant follicular neoplasms, to clarify the diagnostic utility of galectin-3 in aspirates of follicular lesions.


METHODS
A total of 146 follicular lesions diagnosed cytologically, obtained from patients who had undergone thyroidectomy for either benign or malignant nodules, were evaluated using Papanicolaou-stained slides and cell blocks with galectin-3 immunostaining. We primarily categorized the aspirated specimens as benign, indeterminate or suspicious for a follicular neoplasm based on cellularity, architectural arrangement of the follicular cells and presence or absence of colloid. Galectin-3 immunostaining was evaluated according to the proportion and intensity of positively stained cells. Cytologic diagnoses were correlated with the results of galectin-3 and categorized into 3 groups (benign, indeterminate for malignancy, suspicious for malignancy) and compared with the corresponding histologic diagnoses.


RESULTS
When the histologic diagnoses were compared with the cytologic diagnoses, the accuracy in the distinction between benign and malignant cases was 79.5% except for 8 cytologically and 3 histologically indeterminate cases. Except for 11 indeterminate cases, there were 18 (12.3%) discrepant cases. False positive cases included 8 of 62 (12.9%) nodular hyperplasias and 1 of 42 (2.4%) follicular adenomas. Of 9 false negative cases, 4 minimally invasive carcinomas and 2 widely invasive carcinomas were included. Three follicular tumors of uncertain malignant potential were cytologically categorized as malignant, and all cases showed positivity for galectin-3.


CONCLUSIONS
Galectin-3 could be used as a useful supplementary marker for cytologic diagnosis, although it was not an absolute marker in determining whether a lesion was benign or malignant.
Kim
Mi-Jung
MJ
Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, 388-1, Pungnap-dong, Songpa-gu, Seoul, 138-736, Republic of Korea.
Kim
Hyun Jung
HJ
Hong
Suck Joon
SJ
Shong
Young Kee
YK
Gong
Gyungyub
G
D000236:Adenoma / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D014408:Biomarkers, Tumor / Q000378:metabolism*; D044963:Biopsy, Fine-Needle; D002277:Carcinoma / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D005188:False Negative Reactions; D005189:False Positive Reactions; D037502:Galectin 3 / Q000378:metabolism*; D006801:Humans; D006965:Hyperplasia / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D007150:Immunohistochemistry; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D016606:Thyroid Nodule / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology
D014408:Biomarkers, Tumor; D037502:Galectin 3