Evaluation of automated sample preparation system for lymph node sampling

BACKGROUND: Endobronchial ultrasound-guided transbronchial fine needle aspiration (EBUS-FNA) has revolutionized the diagnostic and staging approach to non-small cell carcinoma and thoracic lymphadenopathy. However, obstacles to efficacy of rapid on-site evaluation (ROSE) of the samples include variability in sample quality and slow and cumbersome process in the procedure room leading to extended procedure time. The purpose of this pilot study was to evaluate the feasibility and specimen quality of lymph node biopsies prepared through a novel automated system for automated fixation, drying and staining compared to standard slide preparation method. METHODS: We performed a prospective, single-center pilot feasibility study of patients undergoing EBUS. Samples were split into conventional standard of care (SOC) slide preparation and preparation using the device (“instrument”). Pathologists compared the SOC slides to the slides prepared by the automated system and assessed the following metrics: nuclear and cytoplasmic quality, presence of debris/artifact, staining quality, creation of a monolayer, and ease of adequacy/diagnosis assessment. A score between 1 (lowest quality) and 3 (highest quality) was assigned to the above metrics. RESULTS: Sixty patients were recruited. One to three lymph nodes were sampled for each patient for a total of 72 samples collected. The mean scores of each assessment category showed no statistical difference between the two preparation techniques except for improved monolayer creation in the instrument samples. Thirty of thirty-one (96.8%) paired samples in the final analysis showed diagnostic equivalency between the automated slides and conventional slides; the discordant pairing was reported to be suspicious on the instrument sample and atypical on the SOC. CONCLUSIONS: Study results suggest that slides prepared by the automated system are of adequate quality for adequacy assessment with diagnostic concordance when compared to SOC slides.