Effect of fine needle aspiration biopsy on the histology of thyroid neoplasms

We evaluated the effect of fine needle aspiration biopsy (FNAB) upon the histology of thyroid adenoma and differentiated thyroid carcinoma. When surgery was performed within three months of FNAB, infarction was found histologically in 8/82 (9.8%) of the tumors. It was extensive in four patients, with one patient having no residual neoplastic cells identifiable within the nodule. No infarction was seen in the histologic specimens from patients with similar pathology whose surgery was performed without prior FNAB. These findings confirm previous reports that infarction may be caused by FNAB and can be so extensive as to interfere with the histologic diagnosis.