Treatment strategies of the JALSG ALL202 study. Patients were treated differently according to age and the presence or absence of BCR-ABL fusion transcripts. Pretreatment bone marrow samples were analyzed in a multiplex real-time RT-PCR assay, and the results were obtained within one week. Patients younger than 25 years underwent a 7-day prephase therapy. For patients aged 25 years or older, the first 7 days of treatment were identical for the Ph and the adult non-Ph regimen, but patients were treated differently from day 8 on the basis of the BCR-ABL result. IT indicates intrathecal injection.