A randomized clinical trial reports that in patients with neuroblastoma, tandem autologous stem cell transplant improves outcomes compared with single transplant.
Neuroblastoma, a malignancy of the developing sympathetic nervous system, is responsible for around 10% to 12% of childhood cancer deaths. For the 43% of patients who present with high-risk disease, which involves either widespread metastasis in patients over the age of 18 months and/or amplification of the MYCN oncogene, the standard of care consists of multiagent chemotherapy induction, surgical removal of the tumor, and consolidative high-dose chemotherapy with autologous stem cell transplant, which is followed by radiotherapy, immunotherapy, and treatment with biological agents.
"This approach has resulted in improved overall survival, but relapses occur in 50% to 60% of patients, and more than 90% of patients who relapse die of the disease," write the researchers in their publication in JAMA, led by first author Julie R. Park, MD, Professor of Pediatrics at the University of Washington School of Medicine and Chair in Pediatric Neuroblastoma at Seattle Children's Hospital, where she is also Medical Director of the Immunotherapy Coordinating Center. "Results of nonrandomized clinical trials suggested that intensification of consolidation therapy using sequential or 'tandem' autologous transplant after induction therapy was feasible and may improve outcome in patients with high-risk neuroblastoma."
The trial enrolled 652 eligible patients aged 30 years or younger with high-risk neuroblastoma at 142 Children's Oncology Group centers in the United States, Canada, Switzerland, Australia, and New Zealand between November 2007 and February 2012. Two hundred and ninety-seven patients did not undergo randomization, either because of physician/parent preference (207 patients) or because they were ineligible for randomization (62 patients), were nonrandomly assigned (27 patients), or received no therapy (1 patient). The remaining 355 patients were randomized in a 1:1 ratio to receive either tandem autologous stem cell transplant with thiotepa/cyclophosphamide followed by reduced-dose carboplatin/etoposide/melphalan or single transplant with carboplatin/etoposide/melphalan. Twenty-one patients were lost to follow-up after the completion of protocol therapy; 297 completed the study. The study's primary end point was event-free survival.
Tandem transplant increased the rate of three-year event-free survival compared with single transplant (61.6% vs 48.4%), in addition to decreasing the incidence of mucosal toxicities (11.7% vs 15.4%) and infectious toxicities (17.9% vs 18.3%). The median duration of follow-up after randomization for 181 patients without an event was 5.6 years.
"Among patients aged 30 years or younger with high-risk neuroblastoma, tandem transplant resulted in a significantly better event-free survival than single transplantation," conclude the study authors. "However, because of the low yet anticipated randomization rate, the findings may not be representative of all patients with high-risk neuroblastoma."
For More Information
Park JR, Kreissman SG, London WB, et al (2019). Effect of tandem autologous stem cell transplant vs single transplant on event-free survival in patients with high-risk neuroblastoma: a randomized clinical trial. JAMA, 322(8):746-755. DOI:10.1001/jama.2019.11642
Image courtesy of Dr. Maria Tsokos, National Cancer Institute