OUTLINE: This is a randomized study. Patients are stratified according to participating group (UKCCSG vs SFOP vs CCG), histology (large cell vs small non-cleaved cell), risk group (Group A vs Group B vs Group C). Stage III Group B patients are further stratified according to Murphy stage (stages I/II vs III vs III/IV) and by LDH (less than twice normal vs twice normal or higher). Group C patients are further stratified based on presence of CNS disease (yes vs no).