Expression of matrix metalloproteinase-2, but not caspase-3, facilitates distinction between benign and malignant thyroid follicular neoplasms.
OBJECTIVE
Definite diagnosis of follicular thyroid carcinoma (FTC) is based on the presence of capsular or vascular invasion. To date, no reliable and practical method has been introduced to discriminate this malignant neoplasm from follicular thyroid adenoma (FTA) in fine needle aspiration biopsy material. Matrix metalloproteinase-2 (MMP-2), by degrading extracellular matrix, and caspase-3, by induction of apoptosis, have been shown to play important roles in carcinogenesis and aggressive behavior in many tumor types. The aim of this study was to examine expression of MMP-2 and caspase-3 in thyroid follicular neoplasms and to determine their usefulness for differential diagnosis.


METHODS
Sixty FTAs and 41 FTCs were analysed immunohistochemically for MMP-2 and caspase-3.


RESULTS
MMP-2 was positive in 4 FTCs (9.8%), but in none of FTAs, with statistical significance (p=0.025). Caspase-3 was positive in 30 (50%) of FTAs and in 27 (65.9%) of FTCs.


CONCLUSIONS
Our results show MMP-2 expression only in FTCs and suggest that this protein may be a useful marker to confirm diagnosis of FTC versus FTA with 100% specificity and 100% predictive value of a positive test. We failed to show any differential diagnostic value for caspase-3 in thyroid follicular neoplasms.
Department of Pathology, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Sanaz
S
Sanii
Hiva
H
Saffar
Hedieh M
HM
Tabriz
Mostafa
M
Qorbani
Vahid
V
Haghpanah
Seyed M
SM
Tavangar
D018263:Adenocarcinoma, Follicular / Q000175:diagnosis* / Q000378:metabolism; D000236:Adenoma / Q000175:diagnosis* / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism*; D044963:Biopsy, Fine-Needle; D053148:Caspase 3 / Q000378:metabolism*; D003937:Diagnosis, Differential; D006801:Humans; D007124:Immunoenzyme Techniques; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D009367:Neoplasm Staging; D011379:Prognosis; D012680:Sensitivity and Specificity; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000378:metabolism
D014408:Biomarkers, Tumor; D053148:Caspase 3; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2