Stem Cell Transplant Best for High-risk Leukemia

NEW YORK (Reuters Health) - Stem cell transplant from a compatible related donor results in better outcomes than does chemotherapy in children with very-high-risk acute lymphoblastic leukemia (ALL), the results of an international study suggest.

Dr. Adriana Balduzzi, from Universita degli Studi di Milano Bicocca in Milan, Italy, and her colleagues enrolled 357 patients younger than 18 years with newly diagnosed ALL in a first complete remission between 1995 and 2000. The patients' very-high-risk status was based on failure of initial treatment, certain cellular abnormalities or poor response to prednisone.

The children's families were typed for a compatible related donor search, which formed the basis for treatment allocation. Seventy-seven were assigned to transplant and 280 to chemotherapy. Fifty-five in the transplant group actually underwent transplantation, while 43 in the chemotherapy group underwent transplantation from an unrelated donor.

The results were published online by The Lancet, a UK medical journal.

The five-year disease-free survival rate was 56.7 percent in the transplant group and 40.6 percent in the chemotherapy group, a statistically significant difference.

The advantage of related-donor transplant compared with chemotherapy "became more apparent with every successive year of follow-up, suggesting greater protection against late relapses in children who survived the early toxic effects of treatment," the authors note.

Five-year overall survival was also higher in the transplant group than in the chemotherapy, though the difference did not reach statistical significance, at 56.4 percent versus 50.1 percent, respectively.

The findings also suggest that "the gap between the two strategies increases as the risk profile of the patient worsens." For example, children with initial treatment failure benefited the most from having a related donor compared with those with other risk factors.

SOURCE: The Lancet, August 5, 2005.