The Impact of Rapid On-Site Evaluation on the Quality and Diagnostic Value of Thyroid Nodule Fine-Needle Aspirations

Background: Ultrasound-guided fine-needle aspiration (FNA) is the preferred method to evaluate the dignity of thyroid nodules. Nevertheless, the often-reported high nondiagnostic rate burdens affected patients and the health care system. Rapid on-site evaluation (ROSE) constitutes an addition to the thyroid FNA procedure, with various studies showing its beneficial effect on the Bethesda I nondiagnostic rate. We aimed to assess whether ROSE may reduce the rate of Bethesda categories III and V. Additionally, we examined the influence of ROSE on specimen quality. Methods: We performed a retrospective cohort study, comparing Bethesda categorization and specimen quality in specimens subject to ROSE compared with those not subject to ROSE. We also evaluated aspects of specimen quality that differed according to the use of ROSE. We subcategorized Bethesda I into insufficient cellularity or artifacts, and Bethesda categories III and V into cellular without artifacts, sparsely cellular, or artifacts. Results: We evaluated 5030 thyroid FNAs. ROSE was performed in 1304 (25.9%) cases, and ROSE was not utilized for 3726 (74.1%) specimens. The rate of Bethesda I nondiagnostic and Bethesda III categories was reduced in specimens subject to ROSE (4.3%, 56/1304) compared with non-ROSE (39.9%, 1487/3726, p < 0.001). The rate of both benign Bethesda II and malignant Bethesda VI diagnoses was 91.6% (1194/1270) in ROSE specimens compared with 56.6% (1999/3530) in non-ROSE (p < 0.001). This was reflected by a significant improvement in diagnostic accuracy with ROSE (areas under the curve [AUC]non-ROSE = 0.811, AUCROSE = 0.895, p = 0.004). The overall rate of specimens flawed by sparse cellularity in Bethesda categories III and V was 0.1% (1/1304) in ROSE specimens compared with 1.2% (45/3726) in non-ROSE (p < 0.001). The overall artifact rate was 0.3% (4/1304) for ROSE specimens and 2.5% (92/3726) for non-ROSE (p < 0.001). Conclusions: ROSE significantly increased diagnostic accuracy by improving FNA specimens quantitatively and qualitatively. We suggest considering ROSE as standard of care for thyroid FNAs.