Utility of rapid on-site evaluation (ROSE) using toluidine blue stain in respiratory cytology

Abstract

Introduction and Aim: Cytology has gained importance as a diagnostic test in pulmonary lesions, especially in patients presenting with advanced malignancy which are surgically non-resectable. Although cytopathological diagnosis may be limited, its role cannot be underestimated considering the minimal invasive nature of the technique. Single slide (SS) Rapid on-site evaluation (ROSE) will aid in adequacy assessment and diagnosis of pulmonary lesions on cytopathology. Materials and Methods: We conducted a prospective study. SS ROSE was done on transbronchial fine needle aspiration and bronchial brushing specimens using toluidine blue staining. The slides were microscopically evaluated for adequacy and for diagnosis. In case of inadequate smears, a repeat was suggested. The diagnosis was compared with the diagnosis rendered on remaining slides which were processed using conventional cytology. Results: The study includes 82 cases for ROSE. A correlation of 100% was found between ROSE diagnosis and final cytology diagnosis. Out of 82 cases, 24 cases were malignancies and 3 were granulomatous lesions on ROSE. The remaining were negative for atypical/malignant cells. 2nd pass was advised in 21 cases due to the inadequacy of the diagnostic material in 1st pass. Out of 21 cases advised for 2nd pass, 11 were found to be malignant. A statistically significant p value of 0.05 was obtained. Conclusion: In our study, we found that ROSE using toluidine blue stain is simple, yet a very useful procedure to reduce the number of passes, the need for repeat bronchoscopy procedure and helpful in suggesting more samples for ancillary tests and rapid cytopathological diagnosis.