Transplantation in adult ALL.

The value of the allogeneic graft-versus-leukemia effect in adult acute lymphoblastic leukemia (ALL) has now been conclusively demonstrated and confirmed. While this is true for adults in all age groups, it may not be the best clinical option for young adults for whom increasingly intensive pediatric protocols are clearly of benefit. On the other hand, there is potentially wider applicability of allogeneic donor transplantation for adults 25 to 45 years old, for whom matched unrelated donors may be as safe and effective as sibling donors, and for the patient older than 45 years for whom reduced-intensity conditioning may be a promising way forward. Since the treatment-related mortality of allogeneic transplantation remains significant, careful selection of patients is mandatory. Patients with the Philadelphia chromosome, those with t(4;11) and those with a complex karyotype remain transplant candidates, and allogeneic transplantation remains the best option for salvage, where achievable, in a remission beyond first. As in childhood ALL minimal residual disease studies may be extremely useful in predicting outcome and, therefore, strategy, but at present there are less definite data in adults. Clinical indications to harness the allogeneic effect will mature as the true value of pediatric protocols in adult patients and the safety and efficacy of a sibling, unrelated and reduced intensity transplant emerge in this disease.