Background and study aims Endoscopic ultrasound-guided through-the-needle biopsy (TTNB) of pancreatic cystic lesions (PCLs) is associated with a non-negligible risk for adverse events (AEs). We aimed to identify the hierarchic interaction among independent predictors for TTNB-related AEs and to generate a prognostic model using recursive partitioning analysis (RPA). Patients and methods Multicenter retrospective analysis of 506 patients with PCLs who underwent TTNB. RPA of predictors for AEs was performed and the model was validated by means of bootstrap resampling. Results Mean cysts size was 36.7 mm. Most common diagnoses were intraductal papillary mucinous neoplasm (IPMN, 45 %), serous cystadenoma (18.8 %), and mucinous cystadenoma (12.8 %). Fifty-eight (11.5 %) AEs were observed. At multivariate analysis, age (odds ratio [OR] 1.32, 1.09–2.14; p = 0.05), number of TTNB passes (OR from 2.17, 1.32–4.34 to OR 3.16, 2.03–6.34 with the increase of the number of passes), complete aspiration of the cyst (OR 0.56, 0.31–0.95; p = 0.02), and diagnosis of IPMN (OR 4.16, 2.27–7.69; p < 0.001) were found to be independent predictors of AEs, as confirmed by logistic regression and random forest analyses. RPA identified three risk classes: high-risk (IPMN sampled with multiple microforceps passes, 28 % AEs rate), low-risk (1.4 % AE rate, including patients < 64 years with other-than-IPMN diagnosis sampled with ≤ 2 microforceps passes and with complete aspiration of the cyst) and middle-risk class (6.1 % AEs rate, including the remaining patients). Conclusion TTNB should be selectively used in the evaluation of patients with IPMN. The present model could be applied during patient selection as to optimize the benefit/risk of TTNB.

The management of patients with liver cirrhosis undergoing invasive procedures is controversial and haemostasis assessment using routine laboratory is inappropriate. We evaluated the following: (a) the ability of thromboelastometry to predict the risk of bleeding in cirrhotic patients undergoing invasive procedures and enable a decision on the prophylactic transfusional strategy; (b) the contribution of platelet adhesion and aggregation tests in the assessment of haemostasis. Seventeen cirrhotic patients undergoing invasive procedures were analyzed retrospectively (training set). To obtain preliminary data, an observational study was carried out in 58 patients (test set). All 75 patients were evaluated by thromboelastometry. Platelet adhesion and aggregation were evaluated in 16 patients using Multiplate, PFA-100 and Light Transmission Aggregometry. Factor VIII was dosed in all patients of the test set. In the training set, thromboelastometry confirmed the haemostatic assessment shown by the conventional test only in 6/17 (35%) patients. In the test set, thromboelastometry identified all patients who had a bleeding event. In patients with a high risk of bleeding, the use of thromboelastometry was cost-effective, reducing the platelet infusions by 64%. Platelet adhesion/aggregation abnormalities were observed in 15/16 (94%) patients, but bleeding events occurred only in 2/15 (13%) patients. Thromboelastometry appears to be useful to screen cirrhotic patients undergoing invasive procedures to identify the risk of bleeding and to optimize the transfusional strategy. Adhesion/aggregation tests are not useful in identifying patients at risk of bleeding and their application is not cost-effective.