Successful treatment with third stem cell transplant from an allogeneic donor for a patient with relapsed diffuse large B-cell lymphoma.

High-dose chemotherapy with autologous stem cell transplant is commonly used for diffuse large B-cell lymphoma that recurs after successful salvage chemotherapy. However, in patients in whom the disease recurs again, the prognosis is poor. A 40-year-old woman who underwent allogeneic stem cell transplant 4 years after autologous stem cell transplant developed recurrent diffuse large B-cell lymphoma 3 years after the initial autologous stem cell transplant. She then underwent reduced-intensity hematopoietic stem cell transplant from a human leukocyte antigen-matched, unrelated donor who was not the previous autologous stem cell transplant donor. She achieved a long survival (328 days after the reduced-intensity hematopoietic stem cell transplant and 1844 days after the first allogeneic transplant). A second allogenic transplant may provide survival benefits in a proportion of patients with malignant lymphoma recurring after allogeneic transplant, although careful consideration is required because of the high risk of treatment-related mortality with second allogenic transplant.