Feasibility and results of subtype-oriented protocols in older adults and fit elderly patients with acute lymphoblastic leukemia: Results of three prospective parallel trials from the PETHEMA group

Background and objective: The prognosis of acute lymphoblastic leukemia (ALL) is poor in older adults and elderly patients, and subtype-oriented prospective trials are scarce in these patients. We present the results of three prospective parallel subtype-oriented protocols in fit patients older than 55 years. Patients and methods: In 2008, three prospective phase II trials in patients older than 55 years were activated: ALLOLD07 for Philadephia (Ph) chromosome-negative ALL, ALLOPHO7 for Ph-positive ALL, and BURKIMABO8 for mature B-ALL. Early death (ED), complete remission (CR), disease-free survival (DFS), overall survival (OS) and toxicity were analyzed. Results: 56, 53 and 21 patients from the ALLOLD07, ALLOPHO7 and BURKIMABO8 trials, respectively, were evaluable. CR was 74%, 87% and 70%, with an ED rate of 13%, 11% and 15%, respectively. The medians of DFS were 8 and 38 months for ALLOLD07 and ALLOPHO7 protocols, not being achieved in the BURKIMABO8 trial (p = 0.001), and the median OS was 12, 37 and 25 months, respectively (p = 0.030). Neutropenia, thrombocytopenia and infections were less frequent in the ALLOPHO7 trial vs. ALLOLD07 and BURKIMAB trials, and renal toxicity and mucositis were more frequent in the BURKIMABO8 trial vs. the ALLOLD07 and ALLOPHO7 trials. ECOG score and WBC count had prognostic significance for OS in ALLOPHO7 and BURKIMABO8 trials, whereas no prognostic factors were identified in ALLOLD07 protocol. Conclusion: Subtype-oriented treatment had an impact in the outcome of older adults with ALL. The poorest outcome was observed in Ph-negative non-Mature B-cell ALL patients, for whom improvements in therapy are clearly needed. (C) 2015 Elsevier Ltd. All rights reserved.