A Novel Experience in a Rapid On-Site Evaluation (ROSE) Setting Incorporating Filtration Technology on both Papanicolaou (PAP) and DiffQuick (DQ) Stains

Summary: Introduction: Currently, aliquots of cytology material obtained during ROSE procedure are smeared on slides, air dried and predominantly DQ stained to provide a quick differential between cell types leading to immediate interpretation. Material is subsequently managed by sending it for cellblock, microbiology, and flow cytometry. The patients are under light sedation, so accuracy and speed are paramount. Materials and Methods: Specimen types obtained included endobronchial ultrasound (EBUS), brush biopsy, fine needle aspirate, and touch preps. Cytology material included malignancies (adenocarcinoma - 7 cases, squamous cells carcinoma - 3 cases, small cells carcinoma – 2 cases, various metastases - 3 cases) and benign conditions (benign lymphoid hyperplasia - 5 cases, granulomatous disease - 3 cases). We used a Cell Solutions F50 (CS) - a liquid-based slide prep instrument applying cells on a 12 mm diameter circular area. No centrifugation is necessary, thus avoiding the creation of aerosols in the procedure suite. Each CS slide takes 20 seconds. From each pass an aliquot was used to make three slides; a smear and a CS slide, both air dried for DQ, and a CS slide, alcohol fixed for later PAP stain. DQ stained cytology smear was used for immediate interpretation, QA and downstream comparison. Results: Both malignant and benign conditions were successfully evaluated for specimen adequacy and primary cytomorphology on DQ stained CS slides and smears. CS cytology slides were diagnostically appropriate. Conclusions: A minute amount of material can be immediately processed and accurately interpreted, preserving tissue for cellblock and further – including molecular- studies. Advantages of CS slides include; - smaller area for evaluation leading to shorter ROSE time - cleaner background, free of obscuring blood or indistinct tridimensional cell clusters.