1. No HLA identical (A,B,C,DR,DQ) family donor and no HLA identical unrelated donor available within 3 months of diagnosis or patients whose underlying clinical problems and prognosis would be significantly compromised by chemotherapy conditioning (including persisting pneumonitis, protracted diarrhoea requiring parental nutrition, ongoing visceral viral infection (herpes viruses, HSV,VZV,CMV, EBV or adenovirus), systemic BCG infection, virus-induced lymphoproliferation.