The scientists have revealed that those Leukemia patients, who have got their blood stem cell transplants done, survive just as long as those who undergo the more invasive procedure of having a bone marrow transplant.

Bone marrow transplants involve the collection of stem cells from the bone marrow -- a complicated procedure in which the patient must have a general anesthetic and surgery.

In peripheral blood stem cell transplantation (PBSCT), stem cells are collected from blood, avoiding some of the complications in the case of bone marrow collection.

Researchers conducting a randomized trial, observed that after 10 years, patients with acute lymphoblastic leukemia (ALL) had a survival probability of 28.3 percent after bone marrow transplant compared with 13.0 percent after PBSCT. In patients with acute myeloid leukemia (AML) the probabilities were 62.3 percent for bone marrow and 47.1 percent for blood stem cell transplants.

"Different patient groups might still benefit from transplantation with bone marrow," the researchers concluded.

The researchers noted that many of their findings, including the apparent benefit of preparative total body irradiation, were consistent.