Survival from childhood acute lymphoblastic leukaemia in West Germany: Does socio-demographic background matter?

Abstract

BackgroundSex, age, immunophenotype and white blood cell count at diagnosis are well accepted predictors of survival from acute lymphoblastic leukaemia (ALL) in children. Less is known about the relationship between socio-economic determinants and survival from paediatric ALL, studied here for the first time in German children. MethodsALL cases were diagnosed between 1992 and 1994 and their parents interviewed during a previous nationwide case-control study. Children were followed-up for 10years after diagnosis by the German Childhood Cancer Registry. Cox proportional hazards models estimating hazard ratios (HRs) were calculated to assess the impact of selected socio-demographic characteristics on overall and event-free survival. ResultsOverall survival was 82.5%, with a higher proportion of girls than boys surviving (85% versus 81%). We found a non-linear relationship between age at diagnosis and survival, with poorer survival in infants and children aged >5years. There was no association between socio-economic factors and survival or risk of relapse. For five levels of increasing family income, all HRs were close to one. No relationship was seen with parental educational level. ConclusionSocio-economic determinants did not affect ALL survival in West German children, in contrast to studies from some other countries. Dissimilarities in social welfare systems, including access to health care, lifestyle and differences in treatment may contribute to these differences in findings. Our observation of no social inequalities in paediatric ALL survival is reassuring, but needs continued monitoring to assess the potential impact of evolvement of treatment options and changes in paediatric health service.