The efficacy of the thyroid peroxidase marker for distinguishing follicular thyroid carcinoma from follicular adenoma.
OBJECTIVE
Expression of thyroid peroxidase (TPO) in the thyroid gland tissue is well known as a sensitive marker of the thyroid malignancy. We have evaluated immunohistochemical assay of TPO for distinguishing follicular thyroid carcinoma from follicular adenoma.


METHODS
Sections of formalin-fixed tissues obtained from 92 patients with thyroid tumors (52 follicular carcinomas and 40 follicular adenomas including the Hurthle cell type) were analyzed using a monoclonal antibody (TPO mAb 47) and the avidin-biotin peroxidase complex immunohistochemical technique. Lesions with staining of more than 80% of the follicular cells/specimen were considered benign, while less than 80% were considered malignant.


RESULTS
TPO immunostaining correlated with the histopathological diagnosis in 24/40 cases of follicular adenomas and 41/52 cases of follicular carcinomas, giving a specificity of 60% and a sensitivity of 79%.


CONCLUSIONS
These results suggest that immunohistochemical assay of TPO expression has limited value for the differential diagnosis of follicular thyroid carcinoma from thyroid follicular adenoma.
Savin
S
S
Institute for the Application of Nuclear Energy - INEP, University of Belgrade, Zemun. ssavin@inep.co.yu
Cvejic
D
D
Isic
T
T
Paunovic
I
I
Tatic
S
S
Havelka
M
M
D018263:Adenocarcinoma, Follicular / Q000175:diagnosis / Q000201:enzymology / Q000473:pathology*; D000236:Adenoma / Q000175:diagnosis / Q000201:enzymology / Q000473:pathology*; D014408:Biomarkers, Tumor / Q000032:analysis; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D007453:Iodide Peroxidase / Q000378:metabolism*; D013964:Thyroid Neoplasms / Q000175:diagnosis / Q000201:enzymology / Q000473:pathology*
D014408:Biomarkers, Tumor; D007453:Iodide Peroxidase