BETTER OUTCOMES WITH BONE MARROW TRANSPLANT

Among recipients of hematopoietic stem cell transplants (HSCTs) from unrelated donors, the 5-year patient-reported outcomes were better for patients who received stem cells from bone marrow than those who received stem cells from peripheral blood.

The findings, from a study published online August 11 in JAMA Oncology, suggest that bone marrow should be the preferred source.

"If the goal of hematopoietic cell transplant is to cure patients and restore them to the best health possible, our study recommends that the graft source is important, and patients who receive bone marrow transplants reported better long-term outcomes," lead author Stephanie J. Lee, MD, MPH, of the Fred Hutchinson Cancer Research Center, Seattle, told Medscape Medical News.

This was true of all patient-reported outcomes. "[R]ecipients of unrelated donor bone marrow had the same 5-year survival with better psychological well-being, less burdensome chronic graft-versus-host symptoms, and a higher likelihood of returning to work than recipients of peripheral blood," the researchers report.

At 5 years, more survivors receiving bone marrow transplants returned to full-time or part-time work (52% vs 40%).

Of patients surviving at 5 years, 71% who received bone marrow had no graft-vs-host disease (GVHD), compared with 49% of those who received peripheral blood.

Will the new results change clinical practice? Dr Lee said she hopes so.

At present, around 80% of unrelated donor transplants use peripheral blood as the source hematopoietic stems cells.

Dr Lee noted that there are three main logistical barriers to greater use of bone marrow transplants. Scheduling issues are a major deterrent, she indicated. "It is less complicated to get peripheral blood than bone marrow from donors," she said.

Another significant barrier was physicians' preference for peripheral blood, because it is associated with a lower risk for graft rejection and engraftment is faster. "This is particularly important for patients with an active infection," Dr Lee said. She also noted that patients who are participating in clinical trials are likely to have no option because the use of peripheral blood may be specified in the study protocol in which novel conditioning regimens or GVHD prophylaxis is being evaluated.

"However, in the absence of tailored recommendations for patients, our study shows that bone marrow transplants should be preferred over peripheral blood transplants," Dr Lee said. She added that the study results apply to patients similar to those in the trial (ie, unrelated donor transplants when calcineurin inhibitor/methotrexate-based GVHD prophylaxis is used).

Finally, she indicated that donating bone marrow is harder on the donor because recovery is slower. "[D]onating PB [peripheral blood] is associated with a shorter duration of symptoms than donating BM [bone marrow] so donors may prefer to give PB, although large donor studies suggest that almost all donors recover completely with time," the study authors write.

"In our own practice, we are reexamining graft choices and favoring bone marrow for patients for whom tailored recommendation, clinical trial requirements, or other considerations do not require peripheral blood," Dr Lee told Medscape Medical News. 

Study Details

The new results on patient-reported outcomes come from further data collected from the BMT CTN 0201 study (the primary results were reported in N Engl J Med. 2012;367:1487-1496).

The BMT CTN 0201 study enrolled patients from multiple centers in the United States who had received peripheral blood (n = 273) or bone marrow (n = 278) for hematologic malignancies. The majority of patients received hematopoietic cells for acute myeloid leukemia (47% to 48%), followed by acute lymphoblastic leukemia (21% to 22%) and chronic myeloid leukemia (10% to 14%).

Patient-reported outcomes using validated instruments were collected at 6 months, 1 year, 2 years, and 5 years. Each interview took 30 to 45 minutes.

Functional assessment was determined from the Functional Assessment of Cancer Therapy–Bone Marrow Transplant (FACT-BMT), which comprised the FACT-G and transplant-specific subscales.

The Mental Health Inventory (MHI) determined psychological well-being, psychological distress, anxiety, depression, positive affect, emotional ties, and loss of behavioral and emotional control.

The Lee Chronic GVHD Symptom Scale measured bothersome symptoms in skin, energy, lungs, nutrition, psychological status, eyes, and mouth.

Additional questions provided information on performance status, overall health, overall quality of life, and occupational functioning.

Response rates at 6 months, 1 year, and 2 years were between 28% and 43% of survivors. Response rates at 5 years were between 74% and 78%. The investigators attributed the low response rates before 5 years to central data collection mechanisms being suboptimal. This was "exacerbated by the demands of patients of the early recovery period, particularly at 6 months."

At 5 years, mean FACT-BMT Trial Outcome Index scores were 76 and 69.1 (P = .01) for recipients of bone marrow and peripheral blood, respectively. Corresponding MHI Psychological Well-Being scores were 77.8 and 70.1 (P = .005). For these measures, higher scores are indicative of better functioning and mental health, respectively.

For chronic GVHD symptom scale, scores were 13.0 and 21.2 (P < .001) for recipients of bone marrow and peripheral blood, respectively. Higher scores are indicative of more bothersome symptoms.

In a multivariate analysis, the MHI Psychological Well-Being and the chronic GCVD symptom scale scores continued to be significantly better for patients receiving bone marrow transplants.

Although the data are robust for 5 years, patient-reported outcomes for the intermediate time points were less robust, owing to low response rates from recipients, and the investigators were unable "to confidently comment on these time points."

In their conclusion, the authors write: "It remains to be seen whether the additional information provided by this study will be judged sufficient to recommend BM instead of PB for unrelated donor transplantation when performed for the indications and using the approaches included in the study".