Islet versus pancreas transplantation in Brazil: Defining criteria for pancreas allocation decision.

BACKGROUND: Many studies have evaluated whether there are characteristics related to pancreas donors and the islet isolation process that can influence pancreatic islet yield. However, this analysis has not yet been performed in Brazil, one of the world leaders in whole pancreas organ transplantation (WOPT), where pancreas allocation for pancreatic islet transplantation (PIT) has no officially defined criteria. Definition of parameters that would predict the outcome of islet isolation from local pancreas donors would be useful for defining allocation priority in Brazil. OBJECTIVE: To analyze the relationship between multiple donor-related and islet isolation variables with the total number of isolated pancreatic islet equivalents (IEQ) in a brazilian sample of pancreas donors. METHODS: Several variables were analyzed in 74 pancreata relative to the outcome of total IEQs obtained at the end of the process. RESULTS: In univariate analysis, body mass index (BMI) (p = 0.003), the presence of fatty infiltrates in the pancreas as observed during harvesting (p = 0.042) and pancreas digestion time (p = 0.046) were identified as variables related to a greater IEQ yield. In a multivariate analysis a statistically significant contribution to the variability of islet yield was found only for the BMI (p = 0.017). A ROC curve defined a BMI = 30 as a cut-off point, with pancreata from donors with BMI > 30 yielding more islets than donors with BMI < 30 (p< 0.001). CONCLUSION: These data reinforce the importance of the donor BMI as a defining parameter for successful islet isolation and establishes this variable as a potential pancreas allocation criterion in Brazil, where there is unequal competition for good quality organs between WOPT and PIT.

The presence of bilobar tumor should be considered as a new limit for transplantation beyond the Milan criteria? / A presença de tumor bilobar deve ser considerado novo limite para exclusão de transplante em pacientes que excedem os critérios de Milão?

BACKGROUND: An imprecise estimate of the tumor's aggressiveness of the hepatocellular carcinoma especially in transplanted patients beyond the Milan criteria has a poor outcome, although a more reliable criteria including microscopic vascular invasion is difficult to be established before transplantation. AIM: To examine a cohort of patients with hepatocellular carcinoma undergoing liver transplantation to evaluate the preoperative predicting factors for microscopic vascular invasion. METHODS: A series of 46 consecutive cirrhotic patients with hepatocellular carcinoma undergoing transplantation based on Milan criteria or similar criteria in a single center were enrolled between 1993 and 2007. The survival was calculated using Kaplan-Meyer's method and a multivariate Cox regression was performed to evaluate survival and factors related to microscopic vascular invasion. RESULTS: Multifocal tumors were present in 39 percent. Microvascular invasion, tumor relapses and hepatocellular carcinoma beyond the Milan criteria were identified in 33 percent, 13 percent and 33 percent, respectively. Overall 1-, 3-, and 5-year actuarial patient survival rates were 64 percent, 59 percent and 45 percent respectively. Patients who exceeded the Milan criteria had a higher incidence of microscopic vascular invasion and bilobar tumor compared to those who met the Milan criteria (53 percent vs. 23 percent and 80 percent vs. 19 percent; p<0.05, respectively). After multivariate analysis, the variable identified as independent risk factor for microscopic vascular invasion was the presence of bilobar tumor (hazard ratio, 3.67; 95 percent confidence interval, 1.01 to 13.34; p<0.05). CONCLUSIONS: The presence of a bilobar tumor is more frequent in hepatocellular carcinoma beyond the Milan criteria and it is an independent predictive factor of a high risk of microscopic vascular invasion. The presence of bilobar tumor in hepatocellular carcinoma beyond the Milan ...

RACIONAL: A recidiva tumoral após o transplante de fígado para o carcinoma hepatocelular tem grande impacto desfavorável na mortalidade e a presença de invasão microvascular desempenha papel importante na recidiva tumoral. OBJETIVO: Avaliar a sobrevida, o risco de recidiva tumoral pós-transplante e os fatores relacionados à invasão microvascular de uma série de transplantados por carcinoma hepatocelular. MÉTODOS: No período entre 1993 e 2007 foi estudada uma série consecutiva de 46 cirróticos com carcinoma hepatocelular submetidos à transplante de fígado baseado nos critérios de Milão a partir de 1996 ou critérios semelhantes no período anterior a esta data. Inicialmente todas as variáveis foram analisadas descritivamente, e as quantitativas através da observação dos valores mínimos e máximos, e do cálculo de médias e desvios-padrão e medianas. Para as variáveis qualitativas calcularam-se frequências absolutas e relativas. Realizou-se a regressão logística com ajuste pelo modelo de Cox para avaliar a sobrevida e os fatores relacionados à recidiva tumoral e invasão microvascular. RESULTADOS: A sobrevida da amostra foi de 64 por cento, 59 por cento e 45 por cento para 1, 3 e 5 anos, respectivamente. Em 13 por cento dos casos, a recidiva tumoral foi verificada. A análise multivariada identificou a chance de um paciente com nódulo bilobar sofrer invasão microvascular é 3,67 vezes maior em relação a um paciente com nódulo unilobar e a presença de um tumor unilobar representar um significativo efeito protetor em relação à invasão microvascular (p = 0,048). CONCLUSÕES: A identificação de um tumor bilobar no estadiamento tumoral é fator preditivo independente de maior risco de invasão microvascular e é necessário ainda confirmar se a presença de tumor bilobar deve ser adicionada aos critérios de Milão para melhor indicação de transplante de fígado em pacientes cirróticos com carcinoma hepatocelular.