Follicular and Hurthle cell thyroid neoplasms. Is frozen-section evaluation worthwhile?
A. Paphavasit, G. B. Thompson, I. D. Hay, C. S. Grant, J. A. van Heerden, D. M. Ilstrup, C. Schleck and J. R. Goellner
Division of Gastroenterologic and General Surgery, Mayo Clinic, Rochester, Minn., USA.
OBJECTIVES: To determine whether (1) frozen-section (FS) evaluation of
follicular and Hurthle cell thyroid neoplasms (FHCNs) is accurate, (2) FS
aids in intraoperative decision-making, and (3) FS is cost-effective.
DESIGN: Retrospective review of patient histories and FS and
paraffin-embedded slides. Permanent histologic sections were considered the
standard criterion. Follow-up was achieved in 92% of patients with a mean
follow-up of 5.7 years. SETTING: Tertiary care referral center. PATIENTS:
All patients undergoing thyroidectomy for a suspected FHCN between January
1, 1985, and December 31, 1994. Patients included were those whose
condition was diagnosed as FHCN, either on FS, permanent histologic
sections, or both. MAIN OUTCOME MEASURES: Sensitivity, specificity,
positive predictive value, negative predictive value, and accuracy of FS
analysts were determined. Total adjusted hospital charges were compared for
those undergoing 1 vs 2 cancer operations. Multivariate analyses were
carried out to determine the optimal predictive model for follicular
cancer. RESULTS: The study group included 1023 patients (737 women and 286
men), of whom 83 (8.1%) were diagnosed as having a malignant FHCN on
permanent section. The diagnosis of malignant neoplasm was correctly
established in 65 (78%) of the 83 patients on FS, thereby permitting
definitive surgical management at the first operation. Sensitivity,
specificity, positive predictive value, negative predictive value, and
accuracy for FS diagnosis of malignant FHCN were 78%, 99%, 90%, 98%, and
98%, respectively. In a multivariate analysis, FS was the most significant
variable predictive of malignant neoplasm. Approximately $400,000 was saved
in hospital charges by the use of FS as a result of the elimination of many
2-stage operations. CONCLUSION: Frozen-section evaluation of FHCN can be
performed with a high degree of accuracy, permitting considerable cost
savings.
