Karyometric analysis in the cytologic diagnosis of thyroid lesions.

OBJECTIVE

To assess the possible role of karyometry in improving the diagnostic value of fine needle aspiration biopsy (FNAB) of the thyroid.

STUDY DESIGN

Thyrocyte nuclei were evaluated in routine slides obtained from 229 patients. The cytologic specimens were divided into seven groups according to the results of corresponding postoperative histopathologic examinations. Karyometric measurements comprised assessment of nuclear volume intersection area and perimeter as well as level of anisokaryosis, evaluated as standard deviations of those parameters in single slides. The karyometric evaluation was performed with a computerized image analysis system.

RESULTS

The size of thyrocyte nuclei increased from nontoxic nodular goiters through follicular adenomas, toxic nodular goiters treated with antithyroid drugs, lymphocytic thyroiditis, papillary and follicular carcinomas to anaplastic carcinomas. The observed differences between those groups were statistically significant, but there was marked overlapping. Our data indicate also that the age and sex of the patient influence the cytologic picture of nodular goiter. The evaluation of anisokaryosis increases the usefulness of karyometry in differentiating malignant neoplasms from benign lesions.

CONCLUSION

Karyometric analysis increases the probability of a correct diagnosis with FNAB examination.