Survival rate rises steadily among patients with relapsed ALL after stem cell transplant
The 2-year OS rate nearly doubled during the past 2 decades among patients with Philadelphia chromosome-positive acute lymphoblastic leukemia who relapsed after allogeneic hematopoietic stem cell transplantation, according to study results.
The findings, published in Clinical Cancer Research, indicated the factors associated with the sustained OS increase are likely multifactorial.
“Allogeneic HSCT remains an important and potentially curative treatment modality for various hematologic malignancies, including for patients with [Philadelphia chromosome-positive (Ph+)] ALL. Unfortunately, disease relapse after transplant remains the main cause of failure of allogeneic HSCT,” Ali Bazarbachi, MD, PhD, researcher in the department of internal medicine at American University of Beirut Medical Center in Lebanon, told Healio.
“Relapse after allogeneic HSCT occurs in up to 30% of patients with Ph+ ALL and long-term OS has been dismal,” he said. “In other hematologic malignancies, therapeutic advances resulted in significant improvement over time in survival of patients who relapsed after transplant.”
The retrospective, registry-based, multicenter study included 899 patients with Ph+ ALL in the European Society for Blood and Marrow Transplantation registry who relapsed after allogeneic HSCT.
Bazarbachi and colleagues evaluated changes in patient characteristics, risk factors and clinical outcome between 2000 and 2019, with a median follow-up of 56 months.
Researchers found that 116 patients relapsed between 2000 and 2004, 225 between 2005 and 2009, 294 between 2010 and 2014 and 264 between 2015 and 2019. The patients had a median age at transplant of 44 years and median age at time of relapse of 45.4 years.
Results showed 2-year OS rates after relapse increased from 27.8% between 2000 and 2004 to 54.8% between 2015 and 2019 (P = .001).
“Over time, we saw a steady increase in 2-year survival despite a significant increase in patient age at relapse from 44 to 56 years,” Bazarbachi said.
Moreover, researchers observed an OS rate of 35.9% among the 13.9% of patients who underwent a second allogeneic HSCT within 2 years after relapse. They observed a decrease in 2-year relapse from the time of second transplant from 74% between 2000 and 2004 to 33% between 2015 and 2018.
“We observed a major progressive improvement in OS from post-transplant relapse for patients with Ph+ ALL over the years, which is likely multifactorial including transplant-related factors, post-transplant salvage and improvement in supportive care,” Bazarbachi said. “This real-world outcome may serve as a benchmark to guide the development of new therapeutic strategies in future clinical trials.”
For more information:
Ali Bazarbachi, MD, PhD, can be reached at American University of Beirut Medical Center, P.O. Box 113-6044, Beirut, Lebanon; email: firstname.lastname@example.org.