The value of fine-needle aspiration biopsy (FNAB) in the differential diagnosis of the "cold" thyroid nodule

Introduction: According to the literature, fine needle aspiration biopsy (FNAB) should be the first-line test to assess thyroid nodules. The value of fine needle aspiration biopsy in the differential diagnosis of "cold" thyroid nodules is discussed. Methods: 105 consecutive patients undergoing surgery for solitary cold nodule or a dominant cold nodule in multinodular goiter and having a preoperative fine needle aspiration biopsy, are anlaysed. Results: The cytologic results were benign in 48 cases, malignant in 8 cases and indeterminate (follicular neoplasia) in 29. Twenty biopsies were inadequate. Excluding inadequate and indeterminate biopsy results and calculating microcarcinomas las incidental findings) as "true negative", sensitivity was 56%, specifity 94% and accuracy 88%. There was a negative predictive value of 92% and a positive predictive value of 63%. Conclusions: Fine needle aspiration biopsy is helpful as an additional test. The indication for surgery for a "cold" thyroid nodule must be established in conjunction with clinical findings and other investigation procedures. Key words: Thyroid nodule, fine-needle-aspiration-biopsy, follicular neoplasia, frozen section.