In a retrospective study reported in the Journal of Clinical Oncology, Elizabeth A. Raetz, MD, and colleagues found that outcomes in children and young adults with T-cell acute lymphoblastic leukemia (ALL) who do not achieve remission at the end of induction therapy have improved in contemporary treatment trials but remain poorer than those in patients achieving complete remission at the end of induction.
The study included 325 patients aged ≤ 21 years with T-cell ALL and induction failure treated within 14 cooperative study groups between 2000 and 2018. Induction failure was defined as the persistence of at least 5% bone marrow lymphoblasts or extramedullary disease after 4 to 6 weeks of induction chemotherapy.'
Elizabeth A. Raetz, MD
With a median follow-up of 6.4 years (range = 0.3–17.9 years), 10-year overall survival was 54.7% in the contemporary cohort—higher (P < .0001) than the 10-year rate of 27.6% observed in a historical cohort of 247 patients with induction failure treated from 1985 to 2000. In the current cohort, no significant associations were observed between overall survival and sex, age, white blood cell count, central nervous system disease status, T-cell maturity, or bone marrow disease burden at the end of induction.
Postinduction complete remission with chemotherapy was achieved in 93% of patients in the current cohort; among these patients, 10-year overall survival was 59.6% and 10-year disease-free survival was 56.3%. Among the patients achieving postinduction complete remission, 72% underwent allogeneic hematopoietic stem cell transplantation (HSCT). Among patients undergoing HSCT, 10-year disease-free survival (with 190-day landmark) was 63.8% vs 44.5% among patients who did not undergo HSCT (P = .005), and 10-year overall survival was 66.2% vs 50.8% (P = .10).
The investigators concluded, “Outcomes for patients aged 21 years and younger with T-cell ALL and induction failure have improved in the contemporary treatment era with a disease-free survival benefit among those undergoing HSCT in postinduction first complete remission. However, outcomes still lag considerably behind those who achieve remission at the end of induction, warranting investigation of new treatment approaches.”
Valentino Conter, MD, of the Tettamanti Center, Fondazione IRCCS San Gerardo dei Tintori, Monza, Italy, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by National Cancer Institute grants to the Children’s Oncology Group, American Lebanese Syrian Associated Charities, Deutsche Krebshilfe, and others. For full disclosures of the study authors, visit ascopubs.org.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.