THE IMPACT OF AGE ON OUTCOME IN LYMPHOBLASTIC-LEUKEMIA - MRC UKALL X AND XA COMPARED - A REPORT FROM THE MRC PEDIATRIC AND ADULT WORKING PARTIES

The purpose of the study was to examine the influence of age on outcom e in a large cohort of children and adults with lymphoblastic leukaemi a who were treated on two similar trials. Factors influencing outcome were examined in 2204 patients aged over 1 year treated between 1985 a nd 1992 on the parallel Medical Research Council Trials UKALL X and Xa , for children and adults, respectively. There was a progressive worse ning in survival with increasing age from 85% (95% CI 83-87) at 5 year s for children aged 1-9 to 24% (CI 17-31) for patients over 40. Induct ion failures, deaths in remission and bone marrow relapses increased s ignificantly with age. Analysis of clinical and biological features sh owed dominance of early B-ALL in childhood and increasing incidence of the Ph' chromosome with age. Over 80% of eligible children, but a muc h lower proportion of adults especially those over 40, was entered. Co mpliance was stricter in the paediatric trial but most deviations in a dults involved giving more treatment. Analysis of results in a proport ional hazards model confirmed the overwhelming independent influence o f age; with all other factors equal a 10 year old had half the risk of treatment failure of a 20 year old and a 44 year old double the risk. Selective entry to therapeutic trials and increased treatment-related toxicity are features of adult ALL but age itself remains a dominant prognostic factor. While improved supportive care and refinements of c onventional therapy may have some effect on prognosis, new understandi ngs and treatment approaches to adult ALL are needed.