A Predictive Model for Selecting Malignant Thyroid Nodules in Patients With Nondiagnostic or Indeterminate Fine-Needle Aspiration Cytologic Findings.

Abstract

The management of nodules with nondiagnostic or indeterminate fine-needle aspiration cytologic findings remains challenging. This study evaluated the clinical differences, conventional sonographic findings, elastographic findings, and cytologic findings for predicting thyroid malignancy. A total of 167 patients with a nondiagnostic or indeterminate thyroid fine-needle aspiration cytologic findings were enrolled in this study. The clinicopathologic and sonographic data from the patients were analyzed retrospectively to determine the independent predictive factors for thyroid malignancy. Then a scoring system was designed on the basis of statistically significant predictors. Fine-needle aspiration cytologic findings, Thyroid Imaging Reporting and Data System categorization, and elastographic findings were independent predictive factors for thyroid cancer on multivariate analysis. The index points were statistically significant, with a score higher than 3 favoring malignant nodules with sensitivity of 79.37%, specificity of 85.85%, a positive predictive value of 76.9%, and a negative predictive value of 87.3%. For patients with nondiagnostic or indeterminate fine-needle aspiration cytologic findings, our scoring system for prediction of thyroid malignancy can be another choice. We suggest surgery for nodules with index points higher than 3. For nodules with index points of 3 or lower, observation and regular follow-up are recommended.