Outcomes of endoscopic ultrasound-guided pancreatic FNAC diagnosis for solid and cystic lesions at Manchester Royal Infirmary based upon the Papanicolaou Society of Cytopathology pancreaticobiliary terminology classification scheme.

Objective: To compare endoscopic ultrasound (EUS)-FNAC diagnosis of pancreatic lesions with patient outcome based upon the Papanicolaou Society of Cytopathology pancreaticobiliary terminology classification scheme diagnostic categories: Panc 1 (non-diagnostic); Panc 2 (negative for malignancy/neoplasia); Panc 3 (atypical); Panc 4B (neoplastic, benign); Panc 4O (neoplastic, other); Panc 5 (suspicious of malignancy); and Panc 6 (positive/malignant). Methods: All EUS-FNA pancreas specimens taken at Manchester Royal Infirmary in 2015 were prospectively classified according to the above scheme at the time of cytology reporting and data recorded prospectively. Subsequently, outcomes based on clinical follow-up or histopathology diagnosis were compared with the cytology diagnosis. Results: 120 EUS-FNA pancreas specimens from 111 patients were received, of which 112 (93.3%) specimens had follow-up data. There were 79 and 41 EUS-FNA pancreas specimens from solid and cystic lesions, respectively. Based on the cytology diagnosis the specimens were classified as Panc 1 (7.5%), Panc 2 (33.3%), Panc 3 (2.5%), Panc 4B (2.5%), Panc 4O (15.0%), Panc 5 (3.3%) and Panc 6 (35.9%). The performance indicators for diagnosis of malignancy or neoplasia with malignant potential, included sensitivity (95.4%), specificity (100%), positive predictive value (100%), negative predictive value (92.3%), false positive rate (0%) and false negative rate (4.6%). Conclusions: The Papanicolaou Society of Cytopathology pancreaticobiliary terminology classification scheme is a logical system that can easily be introduced in a diagnostic cytopathology service. This classification scheme acts as an aid to diagnostic reporting, clear communication of significant results including risk of neoplasia/malignancy to clinicians, clinical audit and comparison of results with other centres.