Radiotherapy within the scope of allogeneic kidney transplantation: an indication for local irradiation?

In the past decades the indications for local graft irradiation (LGI) in acute renal transplant rejection have been limited and considered unfavorably. Despite major advantages in maintenance immunosuppression and management of acute allograft rejection a minority of patients remains with drug resistant transplant rejection. This subgroup of patients may benefit from LGI. Between 1979 and 1990, eight patients with biopsy-proven acute renal allograft rejection and failure of all other immunosuppressive measures (corticosteroids, ATG, ALG or OKT3) were treated with LGI. Retrospective analysis was conducted for this control group. Radiotherapy was performed with Co-60 up to a median total dose of 6.0 Gy (single doses: 1.5-2.0 Gy). Six of eight patients were dialysis dependent prior to irradiation. In addition a literature review was performed including most important textbooks, electronic databases (Medline, Embase, Science Citations Index), and the internet. Two of eight patients experienced a clinical reversal of rejection and an improvement of renal function: serum creatinine decreased significantly. One patient remained free of dialysis with a functioning graft, the other had a recurrent rejection 2 months later and became dialysis dependent. The literature review showed, that adjuvant LGI has no advantage over conventional immunosuppression. However, in case of a drug refractory allograft rejection LGI restores long-term stable organ function in 13-60% of cases. The value of LGI of organ transplants, like renal allografts, is still not clearly defined. As a rescue measure in drug refractory allograft rejection special patients may clinically benefit, when a transplant nephrectomy can be avoided. Further prospective clinical trials are needed for a better assessment of LGI in organ transplantation.