High relapse rate of T cell acute lymphoblastic leukemia in adults treated with Hyper-CVAD chemotherapy in Sweden

Abstract

Background: Hyper-CVAD is widely used to treat acute lymphoblastic leukemia (ALL) and aggressive lymphomas. This multicenter, population-based study assessed the efficacy of Hyper-CVAD as first-line therapy in patients with T-cell ALL (T-ALL).

Patients and methods: Between October 2002 and September 2006, 24 patients were diagnosed with T-ALL in Sweden; 19 were eligible for treatment with the protocol.

Results: The median age was 32 yr (range 18-72 yr). Complete remission (CR) was obtained in 17 of 19 (89%) patients, and the treatment was relatively well tolerated. Allogeneic stem cell transplantation (SCT) was recommended in high-risk disease and was performed in four patients upfront. Two- and 5-yr leukemia-free survivals (LFS) in 17 patients with CR achievement were identical, at 29% (95% confidence interval [CI]: 8-51). Two- and 5-yr overall survival (OS) in whole cohort was 63% (95% CI: 42-85) and 47% (95% CI: 26-69), respectively. The 5-yr LFS for 15 patients who did not receive allogeneic SCT upfront were 20% (95% CI: 0-40), although 14 of 15 completed the protocol (eight cycles). Relapse occurred in 2 of 4 upfront-transplanted patients and in 12 of 15 patients treated with chemotherapy alone, six of whom received allogeneic SCT in CR2. Age ≥35 yr influenced OS negatively in univariate analysis (HR 5.1, 95% CI: 1.55-16.7).

Conclusions: Hyper-CVAD treatment resulted in a high CR rate and appeared safe, but it showed poor efficacy at preventing relapse. Therefore, this treatment is no longer recommended for adults with T-ALL in Sweden.

Keywords: antineoplastic combined chemotherapy protocols; precursor T-cell lymphoblastic leukemia-lymphoma; stem cell transplantation; treatment outcome.