The donor cell reinfusion is sometimes used not being used to provide new graft versus leukemia effect but to destroy remaining normal patient cells and to provide engraftment. It has been observed that chimerism is risk factor for relapse of the leukemia. The status of DLI to treat disase is still unsettled and the use of DLI to decrease chimerism is even less established. There would have been no objection to a reinfusion of stem cells to re-engraft which I would see as a continuation of the previously approved stem cell transplant. However, using DLI in this fashion is experimental since the contention that it does os is supported by case reports and series only
Because of the large number of acute leukemia patients who relapse after alloBMT, there has been a substantial experience in the treatment of these patients with DLI. Using median doses of >/=108 T cells/kg, DLI alone induces complete remissions in 8% of patients with ALL and 22% of patients with acute myeloid leukemia (AML). When patients who receive chemotherapy prior to DLI are included, complete response rates are significantly higher, ranging from 33% to 37%. However, follow- up of ALL patients reveals few, if any, long-term survivors, although 1 has been reported. Relapse occurs in approximately one quarter to one half of patients with AML in remission after DLI, leaving a long-term survival rate of approximately 10% to 15%.
DLI has been researched as a treatment for a variety of hematologic malignancies, including most prominently chronic myeloid leukemia, but also acute myeloid leukemia, acute lymphocytic leukemia, multiple myeloma, myelodysplastic syndromes, chronic lymphocytic leukemia, Hodgkin’s disease, and non-Hodgkin’s lymphoma. Studies are limited due to small numbers but they have provided evidence that DLI can establish a graft-versus-leukemia/lymphoma effect.
Fewer patients with relapsed myelodysplasia have been treated with DLI. However, because myelodysplasia progresses more slowly than AML, the rate of complete remissions may be higher. The natural history of myelodysplasia patients who enter into a remission following DLI has not been described.
It is not clear whether administration of induction chemotherapy at the time of relapse improves long-term survival following DLI. It is usually thought that it does but without a strong confirmation in the literature. A randomized trial with analysis performed on an intent-to-treat basis is needed to answer this question.
Litzow, Mark R Progress and strategies for patients with relapsed and refractory acute myeloid leukemia. Current Opinion in Hematology. 14(2):130-137, March 2007.
E . Orsini , E . Alyea , A . Chillemi , R . Schlossman , S . McLaughlin , C . Canning , R . Soiffer , K . Anderson , J . Ritz Conversion to full donor chimerism following donor lymphocyte infusion is associated with disease response in patients with multiple myeloma .
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