A Pancreatic Cystic Neoplasms Drama. Accuracy of Diagnostic Presumption and Surgical Indication on a Ten-year Experience

Abstract

Purpose: Pancreatic cystic neoplasms (PCN) represent a challenging diagnosis despite imaging improvement and guidelines updates. Endoscopic Ultra Sound (EUS) is able to add valuable diagnostic information such as fine needle aspiration (FNA) but the accuracy of this procedure alone is extremely variable and not surely superior to classic MRI and CT-scan. The main aim of this study is to assess the importance of EUS and main cystic features in PCN preoperative work-up in terms of diagnostic accuracy, analyzing at the same those patients with any kind of PCN who could have performed, in retrospect, a close surveillance instead of surgical resection. Method: Patients with a preoperative or pathological diagnosis of PCN were retrospectively reviewed from a prospective database. Data included cases operated from 2010 to 2019 directly or under the supervision of an experienced pancreatic surgery team in three different institutions with a radiologic-oriented diagnostic approach or mixed (radiologic and endoscopic). Preoperative diagnosis was matched with final histology to confirm the diagnostic accuracy of the PCN. Patients with a benign histological who did not show absolute indication on preoperative evaluation, as defined by current guidelines, were categorized as “unrequested surgery”. Results: 587 patients were retrospectively analyzed and in 109/587 cases (18.6%) final histology did not confirm preoperative diagnosis. When performing EUS a significantly lower incidence of diagnostic fallacy was observed (p= 0.024) but risk of overtreatment was similar regardless instrumental diagnostic path (p= 0.356). MPD dilatation and cytologic sampling were the only variables independently related to a correct diagnosis (p <0.001 and p= 0.036). Based on final histology, pancreatic resection could be avoided in 145/461 patients (31.5%). The rate of “unrequested surgery” changed significantly over the years (p= 0.033) and was related with age (p <0.001) , an elevated Ca 19-9 (p= 0.012), cyst dimension (p= 0.023) and type of operation (p <0.001). Conclusions: EUS is an effective procedure in the diagnostic management of PCN, influencing in this series the diagnostic accuracy. Nevertheless, it does not seem to be able to reduce surgical overtreatment. Risk of “unrequested surgery” reduced over the years and it seems correlated with the type of pancreatic resection, being higher for distal pancreatectomies.Tabled 1RadiologicDiagnosis n/tot (%)Radiologic + Endoscopic diagnosis n/tot (%)pDiagnostic accuracyAll cohort148/194 (76.3)330/393 (84)0.024IPMN83/90 (92.2)265/274 (96.7)0.071SCA18/32 (56.3)18/30 (60)0.765MCN29/39 (74.4)25/39 (64.1)0.326Other18/33 (54.5)22/50 (44)0.377Unrequested SurgeryAll cohort46/133 (34.6)99/328 (30.2)0.356IPMN26/90 (28.9)73/274 (26.6)0.678SCA13/32 (40.6)5/30 (16.7)0.038Other7/11 (63.6)21/24 (87.5)0.101 Open table in a new tab Rate of diagnostic accuracy and “unrequested surgery”