Secondary malignancies and quality of life after stem cell transplantation

Malignant diseases (MD) occurring after stem cell transplantation (SCT) are of particular concern as increasing number of patients survive and remain free of their original disease. The cumulative incidence at 15 years is 10-12%. The B-cell proliferative disorders (BCLP) are the most common MD in the first year after SCT; the incidence probability is 1% in allogeneic transplants but is much higher (until 14%) after HLA-identical, T-cell-depleted SCT in which Campath 1G or ATG are given. BCLP develop because of reactivation of the EBV and a depressed cellular immunity. Prediction of risk of BCLP can be made by frequent monitoring of EBV load in patients with risk factors. The most effective therapies are the early administration of anti-CD20 monoclonal antibody and adoptive immunotherapy with in vitro generated EBV-specific cytotoxic T cells. Myelodysplasia and acute myeloid leukemia with very poor prognosis have been described in 4-18% of patients with non-Hodgkin lymphoma and Hodgkin disease, 12-24 months after autologous SCT. The risk of development of solid tumors increases over time and the cumulative incidence among children who underwent an SCT at less than 10 years of age is 6-11% at 15 years. There are few studies evaluating quality of life (QOL) in children and adolescents who had received an SCT. The findings of these studies can be summarized as follows: (a) The majority of long survivors enjoy good QOL and return successfully to school or work. (b) A minority (10-15%) complain of physical problems or present moderate cognitive or psychological dysfunctions. (c) The importance of family, other social support and psychological adjustments is generally recognized. More extensive, longitudinal and comparative studies with other alternative therapies are required.