Segregated graft-versus-tumor effect between CNS and non-CNS lesions of Ewing's sarcoma family of tumors

Abstract

For patients with the localized Ewing's sarcoma family of tumors (ESFT), first-line multimodal treatment, including intensive multi-agent chemotherapy, local radiation therapy and surgery, produces 70–75% of the long-term survival rate.1, 2 However, once patients relapse, there is no effective treatment that yields a 5-year survival rate exceeding 20%, even with high-dose chemotherapy (HDC) with autologous stem cell rescue.3, 4 Therefore, a new and more effective treatment approach is clearly needed for this population. Several reports have described patients with ESFT who had bone marrow metastases and underwent allogeneic SCT instead of autologous SCT,5 including a rare patient who exhibited evidence of a graft-versus-tumor (GVT) effect.6 To accumulate further knowledge, we report the case of a patient with recurrent ESFT who responded to allogeneic SCT from a sibling donor. A unique aspect of this case was that the manifestation of the GVT effect differed in different organs, with involvement of central nervous system (CNS) and non-CNS lesions. The GVT effect is rare in CNS diseases.