The Papanicolaou Society of Cytopathology System for Reporting Respiratory Cytology: To Establish Efficacy and Ease to Use in Routine Cytology Practice

Abstract

ABSTRACT Background: Various pulmonary cytology techniques have been established, representing morphological diversity and ranging from non-invasive to minimally invasive. However, there is currently no widely accepted classification system for respiratory cytology. In 2016, the Papanicolaou Society of Cytopathology (PSC) proposed a six-tiered category system for the cytological sample obtained from the respiratory tract. The diagnostic efficacy of such a category system can help in the early diagnosis of lung cancer patients, thereby reducing mortality and morbidity. Aim: The aim of this study was to determine the diagnostic accuracy and utility of PSC guidelines for reporting respiratory cytology specimens in comparison to histopathology. Materials and Methods: This study was conducted over 6 months, from September 2023 to February 2024, on a prospective basis. Out of a total of 165 samples analyzed, 147 (89%) were bronchoalveolar lavage samples, 09 (05%) were bronchial brushings, 03 (02%) were bronchial washings, and 06 (04%) were endobronchial ultrasound-guided transbronchial fine-needle aspiration. These cytological specimens were processed and categorized according to the PSC reporting system for respiratory cytology, as non-diagnostic, benign, atypical, neoplastic (benign/undetermined malignant potential), suspicious of malignancy, and malignant. In all cases, the histopathological correlation with corresponding transbronchial or endobronchial lung biopsy was done. Results: Our study found that 4% of the cases were non-diagnostic, 80% were benign, 13% were atypical, 2% were suspicious for malignancy, and 1% were malignant. When compared with the histological diagnosis, the sensitivity was 53.13%, the specificity was 93.23%, and the overall accuracy was 85.45%. Conclusion: The PSC reporting system for respiratory cytology can easily standardize reporting patterns to enhance communication between cytopathologists and clinicians, ultimately improving patient care.