1. Liquid-based Cytology for Thyroid Fine-needle Aspiration : Comparison with Conventional Smear Cytology Hyung Suk Seo 1, Heesun Kim 1, Young Hen Lee 1, Ju-han Lee 2 Korea Univ., An-San Hosp., Dept. of Radiology 1, Dept. of Pathology 2 Dept. of Pathology 2

2. Introduction Fine Needle Aspiration (FNA) Best and initial evaluation and diagnosis of thyroid lesion Conventional Smear (CS) Cytology Traditional standard of FNA biopsy Limitation of inadequate sampling low cellularity bloody background

3. Introduction Liquid-based (LB) Cytology SurePath TM (SP) (TriPath Imaging Inc., Burlington, North Carolina, USA) approved by FDA CytoRich ® Red Fixative reduce red blood cells & background debris improved nuclear and cytoplasmic stain Replacing CS cytology in Pap smear or nongynecologic cytology

4. Introduction Comparison between LB and CS Cytology in Thyroid FNA in Previous Study LB cytology higher cellularity, lower nondiagnostic rate clean background slide, easy to interprete more accentuated nuclear irregularity in papillary carcinoma Similar diagnostic accuracy in 2 methods benign & malignant tumors, thyroiditis

5. Purpose Comparison of Diagnostic Adequacy between LB and CS Cytology in Thyroid FNA according to nodular composition according to skill & experience of operator

6. Materials Demographics Total 279 patients mean age: 49.5±12.8 years, M:F=40:239 cytologic proven case :malignancy (30), atypical cell (33), benign (143) Details of retrospective study LB cytologyCS cytology No. of Patients133146 Operator Faculty9876 Resident3570 Time PeriodJUN & JUL, 2009OCT & NOV, 2008

7. Methods Classification of nodular composition by the percentage of cystic portion 3 categories solid ( 50%), spongy-form data number according to nodular composition LB cytologyCS cytology Solid108117 Cystic1819 Spongy-form710 Total133146

8. Methods Diagnostic adequacy of cytology by amount of follicular cells & cellular preservation 2 categories inadequate adequate :including pathologically proven cases as suboptimal and optimal

9. Results Diagnostic adequacy according to nodular composition (ANOVA test) LB cytology superior to CS cytology in solid and cystic thyroid nodule especially, LB cytology much superior in cystic nodule no difference in spongy-form nodule LB cytologyCS cytologyp-value Solid87.0%65.0%<.01 Cystic100%42.1%<.01 Spongy-form85.7%80.0%>.05 Total88.7%63.0%<.01

10. Results Diagnostic adequacy according to operator’s skill (ANOVA test) LB cytology superior to CS cytology in both faculty and resident regardless of operator’s skill LB cytologyCS cytologyp-value Faculty88.8%64.5%<.01 Resident88.6%61.4%<.01 Total88.7%63.0%<.01

11. Conclusion In the ultrasound-guided thyroid FNA, LB cytology can increase the diagnostic adequacy in solid and cystic thyroid nodules. Especially, LB cytology can achieve superior diagnostic adequacy in more than 50% cystic thyroid nodule. LB cytology can increase the diagnostic adequacy by both faculty and resident regardless of operator’s skill. LB cytology may be the method for the optimal diagnostic adequacy instead of CS in thyroid FNA.