Hematopoietic Stem Cell Transplantation in Solid Organ Recipients with Emphasis on Transplant Complications: A Nationwide Retrospective Survey on Behalf of the Japan Society for Hematopoietic Stem Cell Transplantation Transplant Complications Working Group.

Little is known about stem cell transplantation in solid organ transplantation (SOT) recipients. We conducted a nationwide retrospective survey of Japan Society for Hematopoietic Stem Cell Transplantation centers. A total of 19 patients who underwent 22 hematopoietic stem cell transplantations (HSCTs) after SOT were identified: 5 autologous HSCTs and 17 allogeneic HSCTs were performed. Patients who underwent autologous HSCT received a liver (n = 4) or kidney (n = 1) transplant. All 5 patients achieved neutrophil engraftment, and 2 of 3 patients with hepatoblastoma were alive at 1 year after HSCT. Allogeneic HSCT was performed in 16 patients (7 liver transplant recipients and 9 kidney transplant recipients). Among these, 2 donors were identical for both transplantations. All but 1 patient achieved neutrophil engraftment. The 5-year overall survival rate was 41.7%, but that in patients with malignant disease (n = 13) was much lower than the overall rate (23.1%). Only 1 patient with malignant disease underwent allogeneic HSCT in nonremission. In allogeneic HSCT after kidney transplantation, post-transplantation (1 year) kidney function in 5 evaluable patients was significantly lower than that before allogeneic HSCT, and 3 patients experienced renal rejection. However, no severe hepatic rejection was noted. In SOT recipients, HSCT is a potentially curable treatment for hematologic disorders, but it must be performed with caution, especially in patients with malignancy.