Absolutely Continuous Convolutions of Singular Measures and an Application to the Square Fibonacci Hamiltonian

We prove for the square Fibonacci Hamiltonian that the density of states measure is absolutely continuous for almost all pairs of small coupling constants. This is obtained from a new result we establish about the absolute continuity of convolutions of measures arising in hyperbolic dynamics with exact-dimensional measures.Comment: 28 pages, to appear in Duke Math.

Inferring FDG-PET-positivity of lymph node metastases in proven lung cancer from contrast-enhanced CT using radiomics and machine learning

Background: We evaluated the role of radiomics applied to contrast-enhanced computed tomography (CT) in the detection of lymph node (LN) metastases in patients with known lung cancer compared to 18F-fluorodeoxyglucose positron emission tomography (PET)/CT as a reference. Methods: This retrospective analysis included 381 patients with 1,799 lymph nodes (450 malignant, 1,349 negative). The data set was divided into a training and validation set. A radiomics analysis with 4 filters and 6 algorithms resulting in 24 different radiomics signatures and a bootstrap algorithm (Bagging) with 30 bootstrap iterations was performed. A decision curve analysis was applied to generate a net benefit to compare the radiomics signature to two expert radiologists as one-by-one and as a prescreening tool in combination with the respective radiologist and only the radiologists. Results: All 24 modeling methods showed good and reliable discrimination for malignant/benign LNs (area under the curve 0.75-0.87). The decision curve analysis showed a net benefit for the least absolute shrinkage and selection operator (LASSO) classifier for the entire probability range and outperformed the expert radiologists except for the high probability range. Using the radiomics signature as a prescreening tool for the radiologists did not improve net benefit. Conclusions: Radiomics showed good discrimination power irrespective of the modeling technique in detecting LN metastases in patients with known lung cancer. The LASSO classifier was a suitable diagnostic tool and even outperformed the expert radiologists, except for high probabilities. Radiomics failed to improve clinical benefit as a prescreening tool

Conventional versus drug-eluting beads transcatheter arterial chemoembolization (cTACE vs. DEB-TACE) in hepatocellular carcinoma with portal vein thrombosis

Einleitung: Ein Pfortaderthrombus (PVT) wird als ein wichtiger negativer prädiktiver Faktor in Patienten mit hepatozellulärem Karzinom (HCC) angesehen. Diese Studie analysiert und vergleicht die Effektivität und Toxizität von konventioneller trans-arterieller Chemoembolisation (cTACE) und Drug-Eluting Beads (DEB) TACE in Patienten mit HCC und PVT. Methodik: In der vorliegenden retrospektiven Analyse wurden 95 Patienten mit cTACE und 38 Patienten mit DEB- TACE behandelt. Kein Patient wurde mit beiden Modalitäten behandelt. Eine Propensity Score Weighting Analyse wurde für die gesamte Kohorte durchgeführt, speziell wurden Kaplan-Meier Überlebenskurve und Cox –Regressionsanalyse für die Zeit bis zum Todeseintritt angewendet. Nach jeder TACE-Prozedur wurden unerwünschte Ereignisse sowie eine Lebertoxizität Grad ≥ 3 nach dem „National Cancer Institute Common Terminology Criteria for Adverse Events“ (CTCAE), Version 4.03, protokolliert. Zusätzlich wurde eine Untergruppe nach den SHARP Einschlusskriterien („Barcelona Clinic Liver Cancer” [BCLC] C, “Eastern Cooperative Oncology Group performance status” [ECOG PS] ≤ 2 und Child-Pugh Stadium A) generiert, um einen Vergleich mit der initialen Sorafenib-Studie (SHARP-Studie) durchführen zu können. Ergebnisse: Nach dem Propensity Score Weighting konnte kein signifikanter Überlebensunterschied zwischen cTACE [medianes Überleben (MOS) von 5.0 Monaten] und DEB-TACE (MOS von 3.33 Monaten) beobachtet werden (p=0.157). In der Cox-Regressionsanalyse stellten sich ausschließlich ein Child-Pugh Stadium von C vs. A+B (p=0.013; HR, 3.07) und eine Tumorlast von >50% (p=0.0001; HR, 3.02) als unabhängige prädiktive Faktoren in Patienten mit HCC und PVT heraus. Das Post-Embolisationssyndrom [N=57 (30.0%) und N=38 (61.3%)], die Diarrhö [N=3 (1.6%) und N=3 (4.8%)], und die Enzephalopathie [N=11 (5.8%) und N=2 (3.2%)] waren jeweils die häufigsten unerwünschten Ereignisse nach cTACE und DEB-TACE. Die isolierte Überlebensanalyse nach den SHARP Einschlusskriterien zeigte ein MOS von 8.1 Monaten nach cTACE und 5.3 Monaten nach DEB-TACE (p=0.053). Schlussfolgerung: Es konnte kein Unterschied in der Effektivität und Toxizität zwischen cTACE und DEB-TACE in der Therapie vom HCC mit PVT dargestellt werden. Die präsentierten Daten unterstützen nicht die allgemeingültige Hypothese einer unterlegenen Effektivität von intraarterieller Therapie gegenüber der systemischen Therapie von Sorafenib in Patienten mit HCC und PVT innerhalb der SHARP Einschlusskriterien (BCLC C, ECOG PS ≤ 2 und Child-Pugh Stadium A).Purpose: Portal venous thrombosis (PVT) is considered as a major negative predictive factor in patients with hepatocellular carcinoma (HCC). This study analysis and compares the efficacy and toxicity of conventional trans-arterial chemoembolization (cTACE) and drug-eluting beads (DEB) TACE in patients with HCC and PVT. Methods: This retrospective analysis included a total of 95 and 38 patients who were treated either with cTACE or DEB-TACE without cross-over, respectively. A propensity score weighting analysis was performed for the survival analysis of the entire cohort, i.e., Kaplan-Meier survival curve and Cox proportional hazards regression analysis for time to death. After each TACE-procedure adverse events and liver toxicity grade ≥ 3 were recorded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE), version 4.03. Additionally, a comparison to the initial sorafenib study (SHARP trial) was made by generating a sub-group analysis according to the SHARP inclusion criteria [Barcelona Clinic Liver Cancer (BCLC) C, Eastern Cooperative Oncology Group performance status (ECOG PS) 2 and Child-Pugh class A]. Results: After propensity score weighting the overall survival between cTACE [median overall survival (MOS) of 5.0 months] and DEB-TACE (MOS of 3.33 months) was not significant different (p=0.157). Child-Pugh class C vs. A+B (p=0.013; HR, 3.07) and tumor burden >50% (p=0.0001; HR, 3.02) were identified as the only independent predictive factors in patients with HCC and PVT in a multivariate cox proportional hazards regression analysis. Post-embolization syndrome [N=57 (30.0%) and N=38 (61.3%)], diarrhea [N=3 (1.6%) and N=3 (4.8%)], and encephalopathy [N=11 (5.8%) and N=2 (3.2%)] were the most common adverse events after cTACE and DEB-TACE, respectively. The isolated survival analysis according to the SHARP inclusion criteria revealed a MOS of 8.1 vs. 5.3 months after cTACE and DEB- TACE, respectively (p=0.053). Conclusion: No difference in efficacy and toxicity between cTACE and DEB-TACE in the therapy of HCC with PVT could be demonstrated. Further, the presented data does not support an inferior efficacy of intra-arterial therapy over systemic therapy with sorafenib in patients with HCC and PVT within the SHARP inclusion criteria (BCLC C, ECOG PS 2 and Child-Pugh class A)

Additional file 1 of Inferring FDG-PET-positivity of lymph node metastases in proven lung cancer from contrast-enhanced CT using radiomics and machine learning

Additional file 1: Supplementary Figure 1. Representative lymph node metastases. Supplementary Figure 2. Training and cross-validation with LASSO. Supplementary Figure 3. Performance comparison of radiomics in the unsure group (likely benign and likely malignant) to expert radiologists and the effect of encountering the prediction model. Supplementary Figure 4. Performance comparison of radiomics in the unsure group (likely benign and likely malignant) to expert radiologists plotting the 95% confidence interval AUC. Supplementary Table 1. Performance comparison of radiomics and the two expert radiologists. Supplementary Table 2. The effect of encountering radiomics in the unsure group (likely benign and likely malignant) classified by the expert radiologists

Improved Visibility of Metastatic Disease in the Liver During Intra-Arterial Therapy Using Delayed Arterial Phase Cone-Beam CT

PURPOSE: To compare the visibility of liver metastases on dual-phase cone-beam CT (DP-CBCT) and digital subtraction angiography (DSA), with reference to preinterventional contrast-enhanced magnetic resonance imaging (CE-MRI) of the liver. METHODS: This IRB-approved, retrospective study included 28 patients with neuroendocrine (NELM), colorectal (CRCLM), or sarcoma (SLM) liver metastases who underwent DP-CBCT during intra-arterial therapy (IAT) between 01/2010 and 10/2014. DP-CBCT was acquired after a single contrast agent injection in the tumor-feeding arteries at early and delayed arterial phases (EAP and DAP). The visibility of each lesion was graded by two radiologists in consensus on a three-rank scale (complete, partial, none) on DP-CBCT and DSA images using CE-MRI as reference. RESULTS: 47 NELM, 43 CRCLM, and 16 SLM were included. On DSA 85.1, 44.1, and 37.5 % of NELM, CRCLM, and SLM, were at least partially depicted, respectively. EAP-CBCT yielded significantly higher sensitivities of 88.3 and 87.5 % for CRCLM and SLM, respectively (p < 0.01), but not for NELM (89.4 %; p = 1.0). On DAP-CBCT all NELM, CRCLM, and SLM were visible (p < 0.001). Complete depiction was achieved on DSA for 59.6, 16.3, and 18.8 % of NELM, CRCLM, and SLM, respectively. The complete depiction rate on EAP-CBCT was significantly higher for CRCLM (46.5 %; p < 0.001), lower for NELM (40.4 %; p = 0.592), and similar for SLM (25 %, p = 0.399). On DAP-CBCT however, the highest rates of complete depiction were found—NELM (97.8 %; p = 0.008), CRCLM (95.3 %; p = 0.008), and SLM (100 %; p < 0.001). CONCLUSION: DAP-CBCT substantially improved the visibility of liver metastases during IAT. Future studies need to evaluate the clinical impact