Treatment of Frail Older Adults and Elderly Patients With Philadelphia Chromosome-negative Acute Lymphoblastic Leukemia: Results of a Prospective Trial With Minimal Chemotherapy

[Background]: The treatment of acute lymphoblastic leukemia (ALL) in older adults and elderly patients is a challenge, and modern protocols include targeted therapy and immunotherapy in combination with attenuated or minimal chemotherapy. However, frail patients are excluded from these trials, and reports on the outcome of this subgroup of patients are scarce. Our objective was to analyze the outcome of unfit older adults and elderly patients with Philadelphia chromosome-negative ALL included in a prospective trial (ALL-07FRAIL).
[Patients and Methods]: Older adults and elderly patients with Charlson Comorbidity Index (CCI) ≥ 4 were included. Induction therapy consisted of vincristine and dexamethasone, and maintenance therapy with mercaptopurine and methotrexate for 2 years.
[Results]: Seventy-two patients with a median age of 67 years (range, 57-89 years) and a median CCI of 5 (range, 4-12) were included. The rates of early withdrawal, early death, resistance, and complete response (CR) were 5%, 10%, 31%, and 54%, respectively. Six patients with CR abandoned the study, 5 died in CR, and 23 relapsed (cumulative relapse incidence 75%). The medians of disease-free and overall survival (OS) were 6.9 months (95% confidence interval [CI], 0.3-13.5 months) and 7.6 months (95% CI, 6.3-8.9 months), respectively. The most frequent toxic events were hematologic (neutropenia 77% and thrombocytopenia 54%, of grade III-IV in all cases). Eastern Cooperative Oncology Group score but not the CCI had significant impact on OS.
[Conclusion]: Complete remission with very attenuated chemotherapy can be attained in one-half of older or elderly infirm patients with ALL. These results suggest that some of these patients could benefit from the concomitant or subsequent use of immunotherapy and/or targeted therapy.
This study was supported in part by the CERCA Program/Generalitat de Catalunya, Spain and the Josep Carreras Leukemia Research Institute, Badalona, Spain.