Lymphoma patients who are ineligible for a commonly used stem cell transplantation regimen must typically resort to riskier and less effective treatment strategies. New research from a team led by Koen van Besien at Weill Cornell Medical College in New York presents an improved alternative for these patients, which can improve the likelihood of long-term remission. 

Autologous stem cell transplantation entails harvesting a patient’s marrow when their lymphoma is under control. If the cancer recurs, the patient is treated with chemotherapy to eradicate diseased blood cell precursors, which are then replaced with cells derived from the stockpiled, healthy marrow.  

However, many patients are not eligible for this treatment because of characteristics of their disease or their response to prior therapy. “Approximately 30% of our patients are in that group,” says van Besien. Individuals without closely matched donors can receive stem cells from a partially matched donor, which increases risk of relapse, or from umbilical cord blood, which lowers the risk of rejection but greatly delays rebuilding of the immune system.  

Van Besien and colleagues showed that combining two approaches offers the best of both worlds. In this treatment, mature immune cells from partially matched donors temporarily protect the recipients until the immature umbilical cord-derived cells can catch up. Ultimately, these latter cells will become the majority of the immune cell population in most recipients.  

The researchers tracked outcomes for 42 lymphoma and chronic lymphoid leukaemia patients who received this combination treatment, and the outcomes were largely impressive.  

Three years after treatment, 65% of patients were still alive, and 53% of patients reached this stage without disease relapse or signs of graft-versus-host disease. Only 8% of patients were diagnosed with graft rejection. Van Besien found these results encouraging. “This was a group of patients who, until recently, lacked good alternatives,” he says.

 Most clinics still rely entirely on partially matched donor marrow when autologous transplant is not an option and when matching donors are not available. van Besien believes that faster recovery, reduced risk of relapse, and compatibility with less closely-matched donors of the combination approach offer significant advantage. 

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