Involved field radiation therapy and donor lymphocyte infusion for relapsed or refractory non-Hodgkin lymphoma after allogeneic hematopoietic stem cell transplantation

Abstract

Allogeneic hematopoietic stem cell transplantation (HSCT) is an established treatment for Non-Hodgkin lymphomas that are refractory to or relapse after high-dose chemotherapy. Its beneficial effect on disease-free survival or overall survival has been shown e.g. for follicular lymphoma or diffuse large cell B-cell lymphoma. This is not only mediated by the cytoreductive capacity of the conditioning regimen, but also by the graft-versus-malignancy effect of the donor immune system. However, in some cases the lymphoma relapses or is refractory after allogeneic HSCT and only few treatment options are left for those patients. Amongst these, the application of donor lymphocyte infusions (DLI) [1] and involved field radiation therapy (IFRT) have been shown to be effective and feasible for the local control of lymphoma and even the induction of sustained remission [2]. We treated two patients with allogeneic HSCT for diffuse large B-cell lymphoma and marginal zone B-cell lymphoma, respectively. Both relapsed locally and control of remaining lymphomas was achieved by involved field radiation therapy and subsequent donor lymphocyte infusions. E.g., in one patient paragastric lymphoma masses were reduced from 5 cm (Fig. 1a) to 1 cm (Fig. 1b). Although this treatment had considerable side effects, both patients are alive at day ?280 and ?577 after HSCT and have not relapsed since. This case report demonstrates the feasibility and safety of the combination DLI/IFRT for relapsed lymphomas post HSCT. Thus, this combination should be further evaluated as an alternative treatment option for patient who relapse after HSCT or do not respond to it. We