Pediatric‐inspired therapy compared to allografting for P hiladelphia chromosome‐negative adult ALL in first complete remission

For adults with Philadelphia chromosome‐negative (Ph−) acute lymphoblastic leukemia (ALL) in first complete remission (CR1), allogeneic hematopoietic cell transplantation (HCT) is an established curative strategy. However, pediatric‐inspired chemotherapy may also offer durable leukemia‐free survival in the absence of HCT. We compared 422 HCT recipients aged 18–50 years with Ph‐ALL in CR1 reported to the CIBMTR with an age‐matched concurrent cohort of 108 Ph− ALL CR1 patients who received a Dana‐Farber Consortium pediatric‐inspired non‐HCT regimen. At 4 years of follow‐up, incidence of relapse after HCT was 24% (95% CI 19–28) versus 23% (95% CI 15–32) for the non‐HCT (chemo) cohort ( P =0.97). Treatment‐related mortality (TRM) was higher in the HCT cohort [HCT 37% (95% CI 31–42) versus chemo 6% (95% CI 3–12), P <0.0001]. DFS in the HCT cohort was 40% (95% CI 35–45) versus 71% (95% CI 60–79) for chemo, P <0.0001. Similarly, OS favored chemo [HCT 45% (95% CI 40–50)] versus chemo 73% [(95% CI 63–81), P <0.0001]. In multivariable analysis, the sole factor predictive of shorter OS was the administration of HCT [hazard ratio 3.12 (1.99–4.90), P <0.0001]. For younger adults with Ph− ALL, pediatric‐inspired chemotherapy had lower TRM, no increase in relapse, and superior overall survival compared to HCT. Am. J. Hematol. 91:322–329, 2016. © 2015 Wiley Periodicals, Inc.