Diagnostic value of frozen section examination in thyroid nodule--surgery at the Shariati Hospital (1997-2000).

INTRODUCTION

There is controversy regarding the use and accuracy of frozen section (FS) in managing thyroid nodules. We compared the diagnostic value of FS with that of permanent histopathology examination and fine needle aspiration (FNA).

MATERIALS AND

METHODS

Permanent, FS, and FNA sample reports were compared in 214 patients between 1997 and 2000. FS, FNA, and permanent pathology (gold standard) results were compared using McNemar's test.

RESULTS

160 women and 54 men (mean age: 42.3 +/- 5.4 yr) took part in the study; 163 patients (76%) had benign and 51 (24%) malignant lesions; 76% of our thyroid cancer cases were papillary, 13.5% follicular, 6% medullary carcinoma, 4% Hürthle cell carcinoma, and 0.5% anaplastic carcinoma. FNA yielded definite results in 150 patients (sensitivity 72%, specificity 96%, and precision 90%). In 64 patients with equivocal FNA, FS was performed (sensitivity 36%, specificity 73%, and precision 85%). The observed difference between FNA and FS was not statistically significant.

DISCUSSION: When FNA results are inconclusive, FS does not provide any further information. In suspected cases of papillary, undifferentiated, or medullary carcinomas, FS can confirm FNA findings and guide surgical therapy.