Rapid on site evaluation of imprint smear cytology of thoracic endoscopy specimen by a pulmonologist (pROSEI) -Feasibility and diagnostic utility

<bold>Background:</bold> Bronchoscopy and Thoracoscopy are the usual diagnostic procedures performed for acquisition of biopsy specimens for diagnostic purposes in a thoracic endoscopy suite. Imprint cytology involves preparation of touch smears which enables a rapid assessment of the nature of lesion and also the sample adequacy. <bold>Methods:</bold> Consecutive patients who had undergone diagnostic bronchoscopy or thoracoscopy between February - November 2023 were enrolled. After obtaining biopsy of suspected lesions visualiased imprint smears are made and the same biopsy sample is used for histopathological studies. For each case a minimum of 2 imprint smears were made. The imprint cytology slides are evaluated on site by a physician and the results were compared with the final report of a pathologist. <bold>Results:</bold> A total of 80 patients, 54 males and 26 females were included in the analysis. Physician reported imprint smear (pROSEI) had a Sensitivity of 87.10% (95% confidence interval ,76.15% - 94.26%) , Specificity of 66.67% (95% confidence interval 40.99% - 86.66%), Positive Likelihood Ratio 2.61(95% confidence interval 1.35 - 5.06) and Negative Likelihood Ratio 0.19(95% confidence interval 0.09 - 0.40) when compared with the final pathology report. When the sensitivity ans specificity of pROSEI was compared to that reported by the pathologist there was no statistically significant difference(p=0.563) <bold>Conclusion:</bold> There is no statistical difference between the sensitivity and specificity of imprint smears of biopsy specimens as obtained by thoracic endoscopy when read by a physician experienced in interpreting ROSE specimens as compared to a pathologist.