The benefits of the Papanicolaou Society of Cytopathology System for reporting pancreatobiliary cytology: A 2‐year review from a single academic institution

Abstract

Objective Endoscopic ultrasound‐guided fine needle aspiration (EUS‐FNA) is an essential tool in the diagnosis of pancreatic lesions. The aim of this study was to evaluate the diagnostic accuracy of cytology from EUS‐FNA, to correlate the results with the corresponding histopathological diagnoses and to analyse the impact of retrospective assignment of the Papanicolaou Society of Cytopathology (PSC) reporting system categories. Methods All pancreatic FNA specimens reported at the Royal Free Hospital during a 2‐year period were retrospectively collected and assigned to the PSC system categories. Any available corresponding histological samples were assessed for concordance. Results In total, 236 cytology specimens from 223 patients were identified, of which 108 (45.8%) had corresponding histology samples. The main reason for cyto‐histological discrepancy was sampling error. Interpretive error was identified in one case. Overall, sensitivity was 92.5%, specificity was 100%, diagnostic accuracy of cytology was 95%, false‐positive rate was 0% and false‐negative rate was 7.5%. The implementation of the new reporting system reduced the number of cases in the atypical category. All cases previously categorised as suspicious or malignant remained in the same category. Conclusions EUS‐FNA is an accurate method for evaluating pancreatobiliary lesions. The implementation of the Papanicolaou Society of Cytopathology diagnostic system enhances standardisation of the reporting terminology and reduces the number of samples in the non‐standardised and equivocal atypical category.

On-site evaluation of pancreatic lessions according to Papanicolaou Society of Pancreatobiliary Cytology, how can it contribute to diagnostic accuracy?

“…One of our aims in this study was to assess the amount of tissue acquisition and diagnostic accuracy by EUS-FNA biopsy in pancreatic lesions. The compatibility of EUS-FNA PBS-PS categories with nal clinical diagnosis or histopathology was quite high and parallel to the literature [10]. Discordancy with nal diagnoses was observed in 7 of 128 cases with EUS-FNA cytology.…”

The role of cytology in the investigation and management of pancreatobiliary lesions with a transition towards a standardised reporting system: An institutional perspective

“…Our data showed a sensitivity of 93.5%, specificity of 100%, false positive rate of 0%, and a false negative rate of 9%, with a diagnostic accuracy of 96% when using the Papanicolaou system for pancreatobiliary cytology, which is comparable to several other studies emphasising the reproducible results of reporting using this system 24 . When using the C1‐C5 system the sensitivity was 95.7%, the specificity 92.9%, the false positive rate 3.2%, and the false negative rate 13.8%, with a diagnostic accuracy of 94.3%.…”

“…Our data showed a sensitivity of 93.5%, specificity of 100%, false positive rate of 0%, and a false negative rate of 9%, with a diagnostic accuracy of 96% when using the Papanicolaou system for pancreatobiliary cytology, which is comparable to several other studies emphasising the reproducible results of reporting using this system. 24 When using the C1-C5 system the sensitivity was 95.7%, the specificity 92.9%, the false positive rate 3.2%, and the false negative rate 13.8%, with a diagnostic accuracy of 94.3%. Our data support the adoption of the Papanicolaou system as recommended by the Royal College of Pathologists (UK), and in conjunction with other studies in this area demonstrate that the transition produces comparable results to using the previous C1-C5 system; in an increasingly international approach to pathology the use of standardised reporting will allow for safe and effective communication between clinicians and aid in the diagnostic process.…”

Diagnostic Performance of Pancreatic Cytology with the Papanicolaou Society of Cytopathology System: A Systematic Review, before Shifting into the Upcoming WHO International System

“…However, it seems to be of reduced value in pancreatic cystic lesions [35]. Reduction in "atypical" interpretations could be reached by applying ancillary techniques like immunohistochemistry or next-generation sequencing, asking help from experts, or performing a repeat FNA [33,[36][37][38].…”