Probability of survival for pro-B ALL patients treated in GMALL studies 03/87 and 04/89 according to the results of the cytogenetic and molecular analyses. Twenty-two patients with a t(4;11) and/or MLL-AF-4 fusion transcripts (0.41; median, 484 days) and 13 patients with a normal karyotype or other cytogenetic abnormalities (0.40; median, 2,373 days). P (log-rank) = .53.