Thyroid core needle biopsy: taking stock of the situation

Recently, the microhistologic evaluation by core needle biopsy (CNB) has been reported as high accurate to diagnose thyroid nodules with previous indeterminate or not adequate fine-needle aspiration cytology. In addition, sparse data have been reported regarding the use of CNB in other conditions. Aim of this review was to furnish the state of the art of this topic by summarizing published data about the diagnostic performance of CNB in thyroid lesions, and provide an easy to use reference for clinical practice. Sources encompass studies published through May 2014. Original articles were investigated and following specific aspects were discussed: 1. The "large'' needle biopsy in 90's; 2. Complications by and patient's comfort with thyroid CNB; 3. Advantages provided by examination of a microhistologic sample of thyroid nodule; 4. Use of CNB in thyroid nodules with previous not adequate (Thy 1/Class 1/Category I) cytology; 5. Use of CNB in thyroid neoplasms (Thy 3/Class 3/Category III-IV) cytology; 6. Use of CNB in specific ultrasonographic presentations of thyroid nodules or in patients with peculiar clinical contexts; 7. First-line approach by CNB in thyroid nodules; 8. Immunohistochemistry and molecular tests on CNB samples; and 9. Future perspective.