Allogeneic hematopoietic stem cell transplantation for primary cutaneous T cell lymphomas

Cutaneous T-cell lymphomas (CTCL) are a heterogeneous group of non-Hodgkin lymphomas that are considered incurable. The role of allogeneic hematopoietic stem cell transplantation (HSCT) in the treatment of CTCL is not well defined but may provide potent graft-vs-lymphoma (GVL) activity independent of the conditioning therapy. We present outcomes of 12 extensively-pretreated patients with CTCL who underwent allogeneic HSCT using, most commonly, a reduced intensity conditioning (RIC) regimen. Median age at diagnosis of CTCL was 49 yrs, and median time to transplantation from diagnosis was 3.3 years. Transplant induced and maintained CR in 6 patients with active disease supporting the presence of a GVL effect. Transplant related mortality was low, and 42% of patients were alive and disease-free a median duration of 22 months after transplant. Two patients showed strong and direct evidence of a GVL effect with a direct response to withdrawal of immunosuppression or to donor leukocyte infusion (DLI). Our data show that HSCT can provide long-term disease control in patients with advanced CTCL otherwise refractory to immunotherapy and chemotherapy.