Outcome of Severe Aplastic Anemia Treated with Immunosuppressive Therapy Compared with Bone Marrow Transplantation

Abstract

BACKGROUND: We compared response rates and survival after allogeneic bone marrow transplantation (BMT) or immunosuppressive treatment in severe aplastic anemia (SAA) and identified prognostic factors related with survival. METHODS: Medical data of SAA patients who treated with BMT or immunosuppressive therapy (IST) at the Ajou University Hospital from January 1995 to December 2005 were retrospectively analyzed. RESULTS: Total 43 patients were evaluable. 18 patients (41.9%) were treated with IST (antithymocyte globulin plus cyclosporine A plus steroid) and 25 patients (58.1%) were treated with allogeneic BMT. In the IST group, response rate was 77.8%(2 complete remission, 12 partial remission) and there were two treatment failures. As later complications, acute myeloid leukemia developed in 1 patient and myelodysplastic syndrome developed in 2 patients. In the BMT group, response rate was 92.0%(18 complete remission, 5 partial remission) (p<0.001). 6 patients developed grade II to III acute graft-versus-host-disease (GVHD) and 3 patients developed chronic GVHD. The median survival time in all patients was 60.27 months, the 5-year survival rate was 61.0% in the IST group and 81.9%(p=0.144) in the BMT group. The factors influencing overall survival were age under 40-year and positive treatment response. CONCLUSION: This study shows that allogeneic BMT resulted in good response rate and overall survival rate in patients with SAA compared to IST. But overall survival rate between the two groups is statistically insignificant. Our study suggest that the younger age SAA patients with HLA-matched BMT donors may benefit more from allogeneic BMT.

연구배경: 중증재생불량성빈혈 환자를 대상으로 복합면역억제요법과 동종골수이식의 치료성적 및 생존율을 비교하고 이에 관련된 예후인자를 알아보고자 하였다. 방법: 1995년 1월부터 2005년 12월까지 아주대학교병원에서 중증재생불량성빈혈로 진단받고 복합면역억제요법 및 동종골수이식을 시행 받은 환자를 대상으로 임상적 특징, 치료반응, 생존율을 후향적으로 비교분석하였다. 결과: 대상 환자는 43명 이었고, 그 중 18명(41.9%)은 복합면역억제요법 (antithymocyte globulin plus cyclosporine A plus steroid)을 시행하였고, 25명(58.1%)은 동종골수이식을 실시하였다. 복합면역억제요법군에서는 완전반응이 2명(11.1%), 부분반응 12명(66.7%)으로 전체반응은77.8% 였으며, 2명에서 실패하였다. 장기 합병증으로 급성골수성백혈병 1명, 골수형성이상증후군 2명이 있었다. 동종골수이식군에서는 완전반응이 18명(72.0%), 부분반응 5명(20.0%)으로 전체반응은 92.0%(p<0.001)였고, 2-3기의 급성이식편대숙주질환이 6명, 만성이식편대숙주질환이 3명에서 발생하였다. 전체환자의 중앙생존기간은 60.27개월이었으며, 각 군의 5년 생존율은 복합면역억제요법군에서는 61.0%, 동종골수이식군에서는 81.9%였다 (p=0.144). 40세 이하의 나이, 치료에 반응을 보인 경우 통계학적으로 우수한 생존율을 보였다. 결론: 중증재생불량성빈혈의 치료에 있어 동종골수이식이 복합면역억제요법 보다 우수한 반응률을 보였고, 생존율은 통계적 의미가 없었다. 비록 무작위연구는 아니지만, 이번 연구는 조직적합 공여자가 있는 젊은 중증재생불량성빈혈 환자에게 동종골수이식이 일차 치료임을 시사한다.