[Specific cardiomyopathy caused by high dose cyclophosphamide immediately after bone marrow transplantation]

An 11-year-old girl with CML in chronic phase was treated with allogeneic bone marrow transplantation (BMT). She had had no episode of heart disease, and her chest roentgenogram and electrocardiogram were within normal ranges. She had no anthracycline, but 120 mg/kg (2.01 g/m2/d x 2 days) of cyclophosphamide (CY) for conditioning of BMT. She suffered from an acute heart failure on 14 days after BMT and died 2 days later. Autopsy revealed "specific heart muscular disease" with apparent degeneration and necrosis of heart muscle cells. More than 30 fatal cases of CY cardiotoxicity after BMT have been reported, and most patients developed acute heart failure within 10 days after CY dosing. Goldberg et al. reviewed 14 cases of CY cardiotoxicity, and considered more than 1.55 g/m2/day to be the critical doses for the onset of fatal cardiomyopathy. This case was considered to be first case in Japan. CY cardiomyopathy is an early fatal complication of BMT when CY used for conditioning. The dosing schedule may be considered.