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In parametric Bayesian designs of early phase cancer clinical trials with drug combinations exploring a discrete set of partially ordered doses, several authors claimed that there is no added value in including an interaction term to model synergism between the two drugs. In this paper, we investigate these claims in the setting of continuous dose levels of the two agents. Parametric models will be used to describe the relationship between the doses of the two agents and the probability of dose limiting toxicity and efficacy. Trial design proceeds by treating cohorts of two patients simultaneously receiving different dose combinations and response adaptive randomization. We compare trial safety and efficiency of the estimated maximum tolerated dose (MTD) curve between models that include an interaction term with models without the synergism parameter with extensive simulations. Under a selected class of dose-toxicity models and dose escalation algorithm, we found that not including an interaction term in the model can compromise the safety of the trial and reduce the pointwise reliability of the estimated MTD curve.
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INTRODUCTION AND OBJECTIVES: Hepatocellular carcinoma (HCC) is one of the main indications for orthotopic liver transplantation (OLT). In Brazil, selection criteria for HCC is an expanded version of the Milan Criteria (MC), the so-called "Brazilian Milan Criteria" (BMC). Our aims were to evaluate post-OLT outcomes in patients with HCC and analyze the BMC performance. MATERIALS AND METHODS: We conducted a multicenter, retrospective cohort study, analyzing medical records of 1,059 liver transplant recipients with HCC. Tumor was staged according to MC and BMC and correlated with overall survival (OS) and disease-free survival (DFS). We compared the ability of MC and BMC to predict OS and DFS using Delta C-statistic. RESULTS: Post-OLT OS were 63% in five years and HCC recurrence was observed in 8% of patients. At diagnosis, 85% of patients were within MC. Patients within MC at diagnosis and in the explant showed a higher OS and DFS than patients outside MC and within BMC and patients outside both criteria (pâ¯<â¯0.001). Patients outside MC in the explant had an increased risk of tumor recurrence (HR: 3.78; pâ¯<â¯0.001) and poor survival (HR:1.77; pâ¯=â¯0.003). The BMC presented a lower performance than MC in properly classifying patients regarding recurrence risk. CONCLUSIONS: In a large Brazilian cohort of HCC patients submitted to liver transplantation, we observed satisfactory overall survival and recurrence rates. However, patients transplanted within the Brazilian expanded criteria had lower OS and DFS when compared to patients within MC, which may generate future discussions regarding the criteria currently used.
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Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Seleção de Pacientes , Idoso , Brasil , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
To perform statistical inference for time series, one should be able to assess if they present deterministic or stochastic trends. For univariate analysis, one way to detect stochastic trends is to test if the series has unit roots, and for multivariate studies it is often relevant to search for stationary linear relationships between the series, or if they cointegrate. The main goal of this article is to briefly review the shortcomings of unit root and cointegration tests proposed by the Bayesian approach of statistical inference and to show how they can be overcome by the Full Bayesian Significance Test (FBST), a procedure designed to test sharp or precise hypothesis. We will compare its performance with the most used frequentist alternatives, namely, the Augmented Dickey-Fuller for unit roots and the maximum eigenvalue test for cointegration.
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BACKGROUND: Copper deficiency has been linked to alterations in lipid metabolism and hepatic steatosis. Oxidative stress plays a role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). One of the enzymes that neutralize oxidative stress is Cu/Zn superoxide dismutase, which depends on the availability of adequate amounts of copper. OBJECTIVE: Correlate the levels of ceruloplasmin and of non-ceruloplasmin-bound copper (NCBC) with clinical, biochemical and histological parameters of non-alcoholic fatty liver disease (NAFLD) patients. METHODS: Data from 95 consecutively admitted NAFLD patients who underwent liver biopsy composed the groups based on ceruloplasmin levels lower than 25 mg/dL and on negative NCBC. The risk factors for NAFLD in each group were compared. RESULTS: Body mass index was lower in patients with ceruloplasmin <25 mg/dL (29.1±3.47 vs 32.8±6.24 kg/m2; P=0.005) as were the levels of LDL, HDL and total cholesterol, when compared with their counterparts with ceruloplasmin >25 mg/dL (101±38 vs 116±35 mg/dL, P=0.05; 43±9 vs 51±16 mg/dL, P=0.01; 174±43 vs 197±39 mg/dL, P=0.01, respectively). Mean serum ferritin levels were higher in the ceruloplasmin <25 mg/dL group (343±327 vs 197±190 ng/mL; P=0.02). Otherwise, patients with negative NCBC had higher HOMA-IR (8.2±14.7 vs 4.6±3.7; P=0.03). Age, gender, hypertension and diabetes showed no statistical difference. CONCLUSION: Patients with NAFLD had different clinical and biochemical markers according to the levels of NCBC and ceruloplasmin.
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Hepatopatia Gordurosa não Alcoólica , Índice de Massa Corporal , Ceruloplasmina/análise , Ceruloplasmina/metabolismo , Cobre , Humanos , FenótipoRESUMO
ABSTRACT BACKGROUND: Copper deficiency has been linked to alterations in lipid metabolism and hepatic steatosis. Oxidative stress plays a role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). One of the enzymes that neutralize oxidative stress is Cu/Zn superoxide dismutase, which depends on the availability of adequate amounts of copper. OBJECTIVE: Correlate the levels of ceruloplasmin and of non-ceruloplasmin-bound copper (NCBC) with clinical, biochemical and histological parameters of non-alcoholic fatty liver disease (NAFLD) patients. METHODS: Data from 95 consecutively admitted NAFLD patients who underwent liver biopsy composed the groups based on ceruloplasmin levels lower than 25 mg/dL and on negative NCBC. The risk factors for NAFLD in each group were compared. RESULTS: Body mass index was lower in patients with ceruloplasmin <25 mg/dL (29.1±3.47 vs 32.8±6.24 kg/m2; P=0.005) as were the levels of LDL, HDL and total cholesterol, when compared with their counterparts with ceruloplasmin >25 mg/dL (101±38 vs 116±35 mg/dL, P=0.05; 43±9 vs 51±16 mg/dL, P=0.01; 174±43 vs 197±39 mg/dL, P=0.01, respectively). Mean serum ferritin levels were higher in the ceruloplasmin <25 mg/dL group (343±327 vs 197±190 ng/mL; P=0.02). Otherwise, patients with negative NCBC had higher HOMA-IR (8.2±14.7 vs 4.6±3.7; P=0.03). Age, gender, hypertension and diabetes showed no statistical difference. CONCLUSION: Patients with NAFLD had different clinical and biochemical markers according to the levels of NCBC and ceruloplasmin.
RESUMO CONTEXTO: A deficiência de cobre tem sido relacionada a alterações no metabolismo lipídico e esteatose hepática. O estresse oxidativo desempenha um papel fundamental na fisiopatologia da doença hepática gordurosa não alcoólica. Uma das enzimas que neutralizam o estresse oxidativo é a Cobre/Zinco superoxido dismutase, que depende da disponibilidade de quantidades adequadas de cobre. OBJETIVO: Correlacionar os níveis de ceruloplasmina e de cobre não ligado à ceruloplasmina (NCBC) com parâmetros clínicos, bioquímicos e histológicos de pacientes com doença hepática gordurosa não alcoólica (DHGNA). MÉTODOS: Dados de 95 pacientes com DHGNA internados consecutivamente e submetidos à biópsia hepática compuseram os grupos com base em níveis de ceruloplasmina inferiores a 25 mg/dL e em NCBC negativo. Os fatores de risco para DHGNA em cada grupo foram comparados. RESULTADOS: O índice de massa corporal foi menor nos pacientes com ceruloplasmina <25 mg/dL (29,1±3,47 vs 32,8±6,24 kg/m2; P=0,005), assim como os níveis de LDL, HDL e colesterol total, quando comparados aos seus pares com ceruloplasmina >25 mg/dL (101±38 vs 116±35 mg/dL, P=0,05; 43±9 vs 51±16 mg/dL, P=0,01; 174±43 vs 197±39 mg/dL, P=0,01, respectivamente). Os níveis médios de ferritina sérica foram maiores no grupo ceruloplasmina <25 mg/dL (343±327 vs 197±190 mg/mL; P=0,02). Os pacientes com NCBC negativo apresentaram maior HOMA-IR (8,2±14,7 vs 4,6±3,7; P=0,03). Idade, sexo, hipertensão e diabetes não mostraram diferença estatística. CONCLUSÃO: Pacientes com DHGNA apresentaram diferentes marcadores clínicos e bioquímicos de acordo com os níveis de NCBC e ceruloplasmina.
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Humanos , Hepatopatia Gordurosa não Alcoólica , Fenótipo , Ceruloplasmina/análise , Ceruloplasmina/metabolismo , Índice de Massa Corporal , CobreRESUMO
BACKGROUND: Surgical treatment of abdominal hernias in cirrhotics is often delayed due to the higher morbidity and mortality associated with the underlying liver disease. Some patients are followed conservatively and only operated on when complications occur ("wait and see" approach). The aim of this study is to compare outcomes of cirrhotic patients undergoing conservative non-operative care or elective hernia repair. METHODS: A prospective observational study including 246 cirrhotic patients with abdominal hernia was carried out. Patients were given the option to select their treatment: elective hernia repair or conservative non-operative care. Demographics, characteristics of underlying liver disease, type of hernia, complications and mortality were analyzed. During follow-up of patients who opted for the "wait and see" approach, emergency hernia repair was performed in case of hernia complications. RESULTS: Elective hernia repair was performed in 57 patients and 189 patients were kept in conservative care, of which 43 (22.7%) developed complications that required emergency hernia repair. Elective surgery provided better five-years survival than conservative care (80% vs. 62%; p = 0.012). Multivariate analysis identified multiples hernias [Hazards Ratio (HR):6.7, p < 0.001] and clinical follow-up group (HR 3.62, p = 0.005) as risk factors for mortality. Among patients undergoing surgical treatment, multivariate analysis revealed MELD>11 (HR 7.8; p = 0.011) and emergency hernia repair (HR 5.35; p = 0.005) as independent risk factors for 30-day mortality. CONCLUSIONS: Elective hernia repair offers an acceptable morbidity and ensures longer survival. "Wait and see" approach jeopardizes cirrhotic patients and should be avoided, given the higher incidence of emergency surgery due to hernia complications.
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BACKGROUND: Liver transplantation (LT) is the treatment of choice for patients with unresectable early hepatocellular carcinoma (HCC). Post-LT HCC recurrence rates range from 8 to 20% and still impact on overall survival (OS). The aim of our study was to evaluate the impact of HCC recurrence on post-LT survival and analyze prognostic factors among those patients with recurrence. PATIENTS AND METHODS: We carried out a national, multicenter, retrospective cohort study in Brazil. Medical records of 1119 LT recipients with HCC were collected. Data from patients with post-LT HCC recurrence were analyzed and correlated with post-relapse survival. RESULTS: OS of the 1119 patients included in the study was 63% over 5 years. Post-LT HCC recurrence occurred in 86 (8%) patients. The mean time to recurrence was 12 months. Sites of recurrence were extrahepatic in 55%, hepatic in 27%, and both hepatic and extrahepatic in 18%. Recurrence treatment was performed in 50 (64%) cases, mostly with sorafenib. Post-relapse survival rates were 34% at 1 year and 13% at 5 years. Univariable analysis identified α-fetoprotein more than 1000 ng/ml at relapse, recurrence treatment, extrahepatic location, and time to recurrence more than 2 years as prognostic factors. In multivariable analysis, recurrence treatment, extrahepatic location, and time to recurrence more than 2 years were independent predictors of better survival. CONCLUSION: In a large Brazilian cohort of LT recipients with HCC, post-LT HCC recurrence occurred in 8% and impacted significantly on the OS. Patients with early recurrence presented a worse prognosis. However, treatment of recurrence improved outcomes, highlighting the importance of early diagnosis.
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Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Recidiva Local de Neoplasia/epidemiologia , Idoso , Brasil , Carcinoma Hepatocelular/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
BACKGROUND: Cirrhotic cardiomyopathy is characterized by an attenuated contractile response to stress. Long-term exposure of ß-adrenergic receptors to persistently high levels of catecholamines has been implicated in its pathogenesis. We hypothesized that ß-blockade with metoprolol could reverse the changes in heart function and morphology in cirrhotic cardiomyopathy. PATIENTS AND METHODS: In this prospective randomized trial, we included 78 patients aged between 18 and 60 years with abnormal cardiac output response under dobutamine stress echocardiography, without primary cardiac disease or a history of alcohol intake. Patients were assigned randomly to receive metoprolol or placebo for 6 months. The primary endpoint was the improvement in cardiac output response to stress, measured by an increase in the left ventricle stroke volume more than 30%. RESULTS: Three (7.3%) patients in the metoprolol group and nine (24.3%) patients in the placebo group showed improved stroke volume (P=0.057). Diastolic dysfunction was found in two (4.8%) patients before and in five (15.6%) patients after therapy in the metoprolol group, and in 10 (27%) patients before and nine (31%) patients after therapy in the placebo group (P=0.67). After treatment, no echocardiography parameter of morphology was significantly different between metoprolol or placebo groups. No significant differences were observed in noradrenaline, plasma renin activity, and troponin levels between groups. Cirrhosis-related clinical events, including hospitalizations and mortality, were not significantly different between the two groups. Six months of therapy with ß-blocker did not ameliorate heart function and morphology in patients with cirrhotic cardiomyopathy.