Can Bayesian Network empower propensity score estimation from Real World Data?

A new method, based on Bayesian Networks, to estimate propensity scores is proposed with the purpose to draw causal inference from real world data on the average treatment effect in case of a binary outcome and discrete covariates. The proposed method ensures maximum likelihood properties to the estimated propensity score, i.e. asymptotic efficiency, thus outperforming other available approach. Two point estimators via inverse probability weighting are then proposed, and their main distributional properties are derived for constructing confidence interval and for testing the hypotheses of absence of the treatment effect. Empirical evidence of the substantial improvements offered by the proposed methodology versus standard logistic modelling of propensity score is provided in simulation settings that mimic the characteristics of a real dataset of prostate cancer patients from Milan San Raffaele Hospital

The size of well differentiated pancreatic neuroendocrine tumors correlates with Ki67 proliferative index and is not associated with age

Background: Concerns exist about a conservative management of well-differentiated nonfunctioning small pancreatic neuroendocrine tumors (NF-PanNET) in young patients and when preoperative Ki67 proliferative index is >= 3%.Aim: To evaluate an association between age, tumor size and grading in patients with sporadic NF-PanNET who underwent curative resection.Methods: Patients who underwent surgery for sporadic NF-PanNET (excluding G3) were retrospectively analyzed. Linear regression analysis was performed to evaluate a possible correlation between continuous variables, whereas multiple logistic regression analysis was performed for determining predictors of NF-PanNET-G2.Results: Overall, 235 patients with NF-PanNET-G1/G2 were included. The median largest radiological diameter was 25 mm. Age correlated neither with tumor size (P = 0.675) nor with Ki67 index (P = 0.376). On multivariate linear regression analysis, factors independently associated with Ki67 index were NF-PanNET size (P = 0.031), perineural invasion (P = 0.004), microvascular invasion (P = 0.001) and necrosis (P = 0.009). The most accurate NF-PanNET size for predicting NF-PanNET-G2 was 25 mm. On multivariate analysis, a NF-PanNET size >25 mm was independently associated with the risk of having a PanNET-G2 (P = 0.025).Conclusion: No correlations exist between age and NF-PanNET size or proliferative index. Therefore, an a priori aggressive attitude is not justified in young patients with small NF-PanNET, as a long-life expectancy is probably unlikely to increase the risk of malignant transformation. (C) 2019 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved

Ten Year Results of Extensive Nodal Radiotherapy and Moderately Hypofractionated Simultaneous Integrated Boost in Unfavorable Intermediate-, High-, and Very High-Risk Prostate Cancer

Aims: To report 10-year outcomes of WPRT and HD moderately hypofractionated SIB to the prostate in UIR, HR, and VHR PCa. Methods: From 11/2005 to 12/2015, 224 UIR, HR, and VHR PCa patients underwent WPRT at 51.8 Gy/28 fractions and SIB at 74.2 Gy (EQD2 88 Gy) to the prostate. Androgen deprivation therapy (ADT) was prescribed in up to 86.2% of patients. Results: Median follow-up was 96.3 months (IQR: 71–124.7). Median age was 75 years (IQR: 71.3–78.1). At last follow up, G3 GI–GU toxicity was 3.1% and 8%, respectively. Ten-year biochemical relapse-free survival (bRFS) was 79.8% (95% CI: 72.3–88.1%), disease-free survival (DFS) 87.8% (95% CI: 81.7–94.3%), overall survival (OS) 65.7% (95% CI: 58.2–74.1%), and prostate cancer-specific survival (PCSS) 94.9% (95% CI: 91.0–99.0%). Only two patients presented local relapse. At univariate analysis, VHR vs. UIR was found to be a significant risk factor for biochemical relapse (HR: 2.8, 95% CI: 1.17–6.67, p = 0.021). After model selection, only Gleason Score ≥ 8 emerged as a significant factor for biochemical relapse (HR = 2.3, 95% CI: 1.12–4.9, p = 0.023). Previous TURP (HR = 3.5, 95% CI: 1.62–7.54, p = 0.001) and acute toxicity ≥ G2 (HR = 3.1, 95% CI = 1.45–6.52, p = 0.003) were significant risk factors for GU toxicity ≥ G3. Hypertension was a significant factor for GI toxicity ≥ G3 (HR = 3.63, 95% CI: 1.06–12.46, p = 0.041). ADT (HR = 0.31, 95% CI: 0.12–0.8, p = 0.015) and iPsa (HR = 0.37, 95% CI: 0.16–0.83, p = 0.0164) played a protective role. Conclusions: WPRT and HD SIB to the prostate combined with long-term ADT, in HR PCa, determine good outcomes with acceptable toxicity