Supplementary Material for: A Trained Pulmonologist Can Reliably Assess Endosonography-Derived Lymph Node Samples during Rapid On-Site Evaluation

Background: The widespread use of rapid on-site evaluation is hampered by constraints related to time and resources, inadequate reimbursement, and evidence from randomized trials that show a lack of increase in diagnostic yield and specimen adequacy associated with its usage. Objective: We aimed to verify whether a pulmonologist can assess endosonography-derived lymph node samples after a comprehensive and reproducible training provided by a specialist pathologist. Methods:Prospective, observational trial structured in three phases. In the first (training) phase, a pathologist critically evaluated the smears from 150 archival endosonography cases with a pulmonologist. In the second (test) phase, the pulmonologist was asked to assess 50 archival endosonography-derived samples. In the last (real-life) phase, the pulmonologist classified the samples from 200 patients during the endosonography. The overall agreement between pulmonologist and pathologist (gold standard), assessed through κ-statistics, was the primary outcome. The agreement for the identification of specific cytological categories was the secondary outcome. Results: The overallagreement between pulmonologist and pathologist was 84% (κ0.765, 95% CI 0.732–0.826) in the test phase and 89.7% (κ 0.844, 95% CI 0.799–0.881) in the real-life phase. The agreement for specific cytological categories was 92.7% (95% CI 0.824–0.980) for inadequate samples, 90.3% (95% CI 84.5–94.5%) for reactive lymphadenopathies, 90.5% (95% CI 0.845–0.946) for malignancy, and 73% (95% CI 0.515–0.897) for granulomatous samples. Conclusions: A trained pulmonologist can reliably assess adequacy and malignancy for endosonography-derived samples, which could be useful in institutions where a cytopathologist/cytotechnician is not available regularly.