[Prophylaxis and treatment of chronic graft versus host disease].

OBJECTIVE: Chronic graft versus host disease (cGVHD) is the most common late complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and it represents the major cause of mortality in long-term survivors. Over the past decade, although conventional therapy has achieved complete responses in approximately 50% of patients, the prophylaxis and treatment of cGVHD are still not satisfactory. In the late years, utilization of new immunosuppressant such as tacrolimus (FK506), mycophenolate mofetil (MMF) on cGVHD improved the curative effects. This study tried to analyze the results of combination of methylprednisolone (MP), MMF and FK506 or cyclosporine A (CSA) as immunosuppressive therapies for cGVHD and to explore the effective regimen for children.

METHODS: Forty-five patients received allo-HSCT. Among them 32 received UCBT and 13 received PBSCT. The conditional regimen mainly consisted of busalphan, cyclophosphamide, antihuman thymocyte globulin, fludarabin, melphalan, thiotepa and total lymph node irradiation. Prophylaxis of GVHD consisted of CSA, MP and MMF. Patients with cGVHD received a regimen with combination of MP, MMF and FK506 or CSA.

RESULTS: Seventeen out of 32 patients who received UCBT were engrafted. while 9 out of 13 patients who received PBSCT were engrafted. Nine cases of the 30 engrafted patients developed cGVHD (morbidity 30%). Among the 17 patients who received UCBT, 3 developed cGVHD (18%). Among the 13 patients who received PBSCT, 6 developed cGVHD (46%). Six cGVHD continued from aGVHD (6/9). One patient was given CSA plus MMF, and 8 were given three-drug regimen with MP, MMF and FK506. The overall response rate was 100%. Two patients died of CMV-IP or septicemia (mortality 20%). Seven (78%) patients survived (event free survival, EFS) longer than 3 years. The side effects included hepatotoxicity, nephrotoxicity, hypertension, articular capsulitis and arrhythmia. The main complication and the major causes of death were infection.

CONCLUSION: The incidence of cGVHD is low in children. The incidence of cGVHD after PBSCT is higher than that after UCBT. aGVHD is a highly dangerous factor. Combined therapy of MP plus MMF and FK506 or CSA is safe and effective for the treatment of cGVHD in children.