Journal of Cytology (Jan 2008)
Cytodiagnosis of thyroid lesions-usefulness and pitfalls: A study of 288 cases
Abstract
Background: Fine needle aspiration cytology (FNAC) of the thyroid gland has been widely and successfully utilized for diagnosis. Aim: Our aim was to demonstrate the effectiveness of this cheap and simple procedure for the diagnosis of different thyroid lesions, particularly, differentiation of malignant and nonmalignant lesions. In addition, we sought to highlight probable causes of error and possible remedies in the cases showing lack of correlation between cytological and histological diagnoses. Materials and Methods: A total of 288 cases of thyroid swellings were aspirated in our two-year study period. Cases were divided into four groups, namely, aspiration inadequate where diagnosis was not offered; a nonneoplastic group which included different goiters and thyroiditis; an indeterminate group which included cases showing features of follicular or Hurthle cell neoplasms, and a malignant group that included nonfollicular malignant tumors of the thyroid. Cases showing cytohistologic disparity were reevaluated. Results: Almost 14% of the cases could not be reported because of inadequate aspiration, however, an overall cytohistological correlation was achieved in 82.66% of all cases. Sensitivity and specificity for the diagnosis of malignancy were 92.7 and 98.2%, respectively. There were four false negative malignant cases with one false positive case and 13 cases failed to show any cytohistological correlation. Conclusions: FNAC is the single most important test for preoperative assessment of thyroid pathology if attention is paid to the clinical features and collection of samples from proper sites.
