No more transplantation in CML?

To the editor:

Hehlmann et al¹  report that drug treatment is superior to allografting in the first-line therapy of chronic myeloid leukemia (CML). In the accompanying Inside Blood commentary, Guilhot²  concurs and concludes “that allogeneic stem cell transplantation cannot be recommended for front-line therapy.” The study by Hehlmann et al compared the outcome, by genetic randomization, of sibling allogeneic transplantation with best medical care (mainly hydroxyurea and interferon). The medically treated patients had a superior survival to the allogeneic transplantation patients until 8 years of follow-up, when the curves joined. There were no data beyond 11 years of follow-up. The median age of patients in this study was 40 years and only around 4% of the patients were younger than 20 years of age.

Data from the European Group for Blood and Marrow Transplantation (EBMT)³  show that about 41% of patients with chronic-phase CML that received transplants will be alive at 20 years (49% in those with EBMT score 0-1) and that in children the 10-year overall survival is 65% to 70%.⁴ 

An expert committee has recently reviewed the exciting data on imatinib but concluded that there is an insufficient evidence base as yet on which to draw conclusions about survival.⁵ 

The study by Hehlmann et al provides excellent data on which to advise patients with a median age of 40 about the most appropriate treatment to give them the best chance of being alive and well 8 to 10 years from diagnosis. It does not provide the data on which to advise children and young adults with CML on the treatment most likely to result in their survival into their eighth or ninth decades of life. We simply do not know the answer to this question and therefore it is premature to conclude that bone marrow transplantation cannot be recommended as front-line treatment.