The applicability of Papanicolaou Society of Cytopathology system on reporting endoscopic ultrasound-guided fine needle aspiration cytology specimens of pancreatic lesions in situations with limited availability of ancillary tests. Experience at a single laboratory

Systematic review and meta-analysis of the Papanicolaou Society of Cytopathology (PSC) system in diagnosing pancreatic lesions: Evaluating diagnostic accuracy

INTRODUCTION

The 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.

METHODS

A 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.

RESULTS

Twelve 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%).

CONCLUSION

This 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.

Grading pancreatic adenocarcinomas on fine needle aspiration cytology. The outstanding issues

OBJECTIVE

The three-tier grading scheme described in "The Papanicolaou Society of Cytopathology (PSC) System for reporting Pancreaticobiliary Cytopathology" (TPSCRPBC) which remained unchanged following the WHO Reporting System for Pancreaticobiliary Cytopathology (WRPBC) was evaluated on pancreatic adenocarcinomas (PACs) reported on endoscopic ultrasound-guided fine needle aspiration cytology (EUS-FNAC).

METHODS

The Papanicolaou and May Grunwald Giemsa-stained smears from 116 cases of PACs were graded using the three-tier grading scheme laid down by TPSCRPBC/WRPBC. Cases exhibiting multiple grades were assigned primary, secondary and tertiary grades. Each case was assigned a grade score, either by adding the primary and secondary grades, by adding the primary and tertiary grades when the tertiary grade was 3 or by doubling the grade when only one grade existed. Necrosis was estimated semi-quantitatively. The inter-observer reproducibility in grading was evaluated using Kappa and Kendall's tau-c. Correlations between the various grades, the stage of the tumour and the amount of necrosis were assessed using Spearman rho and Kendall's tau-b.

RESULTS

31.89% of cases showed one grade, and 68.11% showed at least two grades. 16.38% showed three grades. The two commonest grade scores were 3 and 5. The inter-observer reproducibility for grading and grade scoring was satisfactory. A positive correlation was noted between the grades and the amount of necrosis. No significant correlation was found between the grades, grade scores and the stage of the tumours.

CONCLUSIONS

The TPSCRPBC/WRPBC grading scheme can be suitably applied to PACs with good inter-observer reproducibility. Cases often show multiple grades in the same tumour.

Humoral Predictors of Malignancy in IPMN: A Review of the Literature

Pancreatic cystic lesions are increasingly detected in cross-sectional imaging. Intraductal papillary mucinous neoplasm (IPMN) is a mucin-producing subtype of the pancreatic cyst lesions arising from the pancreatic duct system. IPMN is a potential precursor of pancreatic cancer. The transformation of IPMN in pancreatic cancer is progressive and requires the occurrence of low-grade dysplasia, high-grade dysplasia, and ultimately invasive cancer. Jaundice, enhancing mural nodule >5 mm, main pancreatic duct diameter >10 mm, and positive cytology for high-grade dysplasia are considered high-risk stigmata of malignancy. While increased levels of carbohydrate antigen 19-9 (CA 19-9) (>37 U/mL), main pancreatic duct diameter 5-9.9 mm, cyst diameter >40 mm, enhancing mural nodules <5 mm, IPMN-induced acute pancreatitis, new onset of diabetes, cyst grow-rate >5 mm/year are considered worrisome features of malignancy. However, cross-sectional imaging is often inadequate in the prediction of high-grade dysplasia and invasive cancer. Several studies evaluated the role of humoral and intra-cystic biomarkers in the prediction of malignancy in IPMN. Carcinoembryonic antigen (CEA), CA 19-9, intra-cystic CEA, intra-cystic glucose, and cystic fluid cytology are widely used in clinical practice to distinguish between mucinous and non-mucinous cysts and to predict the presence of invasive cancer. Other biomarkers such as cystic fluid DNA sequencing, microRNA (mi-RNA), circulating microvesicles, and liquid biopsy are the new options for the mini-invasive diagnosis of degenerated IPMN. The aim of this study is to review the literature to assess the role of humoral and intracystic biomarkers in the prediction of advanced IPMN with high-grade dysplasia or invasive carcinoma.