A Cost-Effectiveness Analysis of Thyroid Frozen Sections
S M Voss, H S Crist, H Mani. PSMSHMC, Hershey, PA
Background: Routine use of frozen sections (FS) during thyroid surgery continues to be controversial. Studies have advocated the use of FS only in cases labeled suspicious or indeterminate on cytology (FNAC). We performed a cost-effectiveness analysis of thyroid FS use to evaluate the above strategy.
Design: A retrospective analysis of the pathology database was performed to identify thyroid FS over a 7-year period. Results of FNAC, FS and final pathology (FHP) were collated and data analyzed. Cost effectiveness was analyzed based on medicare reimbursement rates for FNAC ($134), FS ($89), surgery (lobectomy $767, thyroidectomy $970) and FHP ($219).
Results: 152 thyroid FS were carried out in the study period. FS diagnoses correlated with FHP in 128 (84%) cases (33 malignant and 95 benign). FS had a sensitivity of 64% and specificity of 94%. 115 cases had satisfactory FNAC, with a sensitivity of 73% and specificity of 64%. Of the 33 cases diagnosed as malignant on FS, 17 had a diagnosis of malignancy on FNAC and FS did not add to the surgical strategy in these cases. FS changed the surgical strategy in 20 (13%) cases that were not malignant by FNAC. Diagnoses on FS and FHP in non-malignant FNAC categories are shown in Table 1. False negative diagnoses on FS included 11 papillary carcinomas (8 micro and 3 follicular variant) and 3 minimally invasive follicular carcinoma.
|Benign||25 benign, 6FN, 3PTC||27 benign, 3 PTC, 4 uCa|
|FN||19 benign, 23 FN, 3 PTC||39 benign, 3 PTC, 2 uCa, 2FCa|
|Suspicious||4 benign, 5 FN, 6 PTC||8 benign, 7 PTC|