Azacitidine therapy for low-risk myelodysplastic syndrome developing after solid organ transplantation

Immunosuppressive therapy after solid organ transplantation is known to be a risk factor for the development of myelodysplastic syndromes (MDS). Herein, we report 2 patients, both of whom developed low-risk MDS after solid organ transplantation and were successfully treated with azacitidine (AZA). The 1st case was a 74-year-old man who had received liver transplantation. The initial immunosuppressive therapy consisted of cyclosporine and prednisolone. Nine years after transplantation, he was diagnosed as having MDS (RCMD). The 2nd case was a 47-year-old woman who had received cadaveric renal transplantation. The initial immunosuppressive therapy was comprised of cyclosporine, azathioprine, and prednisolone. Twenty-seven years after transplantation, she developed MDS (RA). Both patients received 75 mg/m² AZA once daily for five consecutive days on a 28-day cycle. After 2 courses of therapy, both patients achieved hematological improvement (IWG 2006 criteria) without severe (grade 3/4) non-hematological adverse events. Moreover, AZA did not affect the status of organ transplantation in terms of engraftment and function of the graft. In conclusion, AZA would be a safe and effective agent for patients with MDS after solid organ transplantation. However, long-term follow-up is needed to confirm the safety and efficacy of AZA for patients undergoing solid organ transplantations.