INTRODUCTIONThe Papanicolaou system plays a vital role in cytological evaluation, particularly in the diagnosis of pancreatic lesions. However, there is a lack of comprehensive evaluation regarding its diagnostic accuracy in pancreatic fine needle aspirations (FNAs). This study seeks to address this gap by conducting a systematic review and meta-analysis to assess the diagnostic accuracy of the Papanicolaou Society of Cytopathology (PSC) system in diagnosing pancreatic lesions.METHODSA systematic search of PubMed and EMBASE databases was conducted up to March 20, 2024, using predefined search terms related to pancreas, fine needle aspiration biopsy (FNAB), and diagnostic accuracy. The selected articles were assessed for risk of bias using the QUADAS-2 tool. A meta-analysis for sensitivity and specificity for each cut-off - namely, "Atypical considered positive", "Neoplastic considered positive", "Suspicious of Malignancy considered positive," and "Malignant considered positive" - was performed after excluding inadequate samples in each study. To assess diagnostic accuracy, summary receiver operating characteristic (sROC) curves were constructed, and the diagnostic odds ratio (DOR) was pooled.RESULTSTwelve studies met the inclusion criteria, comprising a total of 3604 cases. Sensitivity and specificity varied across the PSC categories, with the "Malignant" category showing the highest sensitivity (70%) and specificity (99%). The "Suspicious for malignancy and higher risk categories" demonstrated high sensitivity (81%) and specificity (97%).CONCLUSIONThis meta-analysis underscores the accuracy of the PSC system in reporting pancreatic aspirates. It highlights the significance of the "Suspicious" and "Malignant" categories in diagnosing malignancy, as well as the "Benign" and "Atypical" categories in ruling out malignancy.