Autologous stem cell transplant in ALL: who should we be transplanting in first remission?

Long-term disease-free survival (DFS) has been reported after autologous stem cell transplantation for acute lymphoblastic leukemia. Phase II studies have evaluated its role in first and subsequent complete remission (CR) with DFS rates of up to 50%. It has been under-utilized in 1st CR in part, due to a concern that patients who relapse after autologous stem cell transplantation (ASCT) have fewer options for salvage treatment of relapsed disease. Unfortunately, survival rates of <5% are reported in patients who relapse, regardless of initial therapy. Few prospective, randomized trials have analyzed large enough numbers of patients to allow us to determine the appropriate patient population for autologous transplantation. Although variability in the available studies makes it difficult to draw a definite conclusion, and many issues remain unresolved, available data suggests that there may be a group of patients for whom ASCT in first remission is a reasonable and perhaps superior treatment choice. Factors such as risk features at diagnosis, and minimal residual disease following induction therapy greatly affect outcome following ASCT. The available data as well as the questions that remain to be answered will be discussed and reviewed.