Frozen section in thyroid surgery.

Objective: We studied the use of frozen section in the detection of malignancy in thyroid surgery in a large teaching hospital.

Materials And Methods: We reviewed all case notes of patients operated on for thyroid disease between January 1st 1997 and December 31st 2004. We identified 420 operations in 408 patients. Data were available for 417 operations.

Results: In patients with a solitary thyroid nodule, a frozen section is sometimes performed. Frozen section was done in 128 of 417 operations. The specificity for malignancy was 98.16%. The positive predictive value was 81.81% and the negative predictive value 93.85%. However the sensitivity was 56.25%. Frozen section is a time-consuming investigation. With follicular lesions it is very difficult to distinguish between benign disease and malignancy since the diagnosis of malignancy depends on capsular and/or blood vessel invasion. Also it costs about 100 Euro (approximately 125 dollars).

Conclusion: This study confirms that adequate histopathologic diagnosis of thyroid disease is based on extensive subsampling of the specimen which is not possible during a peroperatory frozen section procedure.