Randomized prospective evaluation of frozen-section analysis for follicular neoplasms of the thyroid

Objective To evaluate the clinical utility of frozen section in patients wi th follicular neoplasms of the thyroid in a randomized prospective trial. Summary Background Data The finding of a follicular neoplasm on fine-needle aspiration prompts many surgeons to perform intraoperative frozen section during thyroid lobectomy. However, the focal distribution of key diagnostic features of malignancy contributes to a high rate of noninformative frozen sections. Methods The series comprised 68 consecutive patients with a soli tary thyroid nodule in whom fine-needle aspiration showed a follicular neop lasm. Patients were excluded for bilateral or nodal disease, extrathyroidal extension, or a definitive fine-needle aspiration diagnosis. Final patholo gic findings were compared with frozen sections. and cost analyses were per formed. Results Sixty-one patients met the inclusion criteria. Twenty-nine were ran domized to the frozen-section group and 32 to the non-frozen-section group. In the non-frozen-section group, one patient was excluded when gross exami nation of the specimen was suggestive of malignancy and a directed frozen s ection was diagnostic of follicular carcinoma. Frozen-section analysis rend ered a definitive diagnosis of malignancy in 1 of 29 (3.4%) patients, who t hen underwent a one-stage total thyroidectomy. In the remaining 28 patients , frozen section showed a "follicular or Hurthle cell neoplasm." Permanent histology demonstrated well-differentiated thyroid cancer in 6 of these 28 patients (21%). Of the 31 patients in the non-frozen-section group, 3 (10%) showed well-differentiated thyroid carcinoma on permanent histology. Compl ications were limited to one transient unilateral vocal cord dysfunction. A ll but one patient had a 1-day hospital stay. There were no significant dif ferences between the groups in surgical time or total hospital charges; how ever, the charge per informative frozen section was approximately $12,470. Conclusions For the vast majority of patients (96.4%) with follicular neopl asms of the thyroid, frozen section is neither informative nor cost-effecti ve.