Long-term follow-up after allogeneic stem cell transplantation.

Background: Over 3000 persons undergo allogeneic hematopoietic stem-cell transplantation (allo-HSCT) in Germany every year. Advances in allo-HSCT have prolonged the survival of treated patients but have concomitantly increased the risk of long-term complications that impair their quality of life.

Methods: This literature review of the long-term sequelae of allo-HSCT is based on pertinent articles that were retrieved by a selective search of PubMed, and on current international guidelines. Case reports were excluded from consideration.

Results: Hardly any randomized clinical trials have been performed to investigate the long-term outcome of allo-HSCT, but international consensus-based guidelines have been published. 50% to 70% of patients treated with allo-HSCT develop chronic graft-versus-host disease (cGVHD) within ten years of treatment. Transplant recipients are at higher risk of infection, including the reactivation of dormant herpes viruses; therefore, vaccination is recommended, as described in the current guidelines. Gonadal dysfunction arises in up to 92% of men and up to 99% of women; its frequency depends on the timing of transplantation, on radiotherapy, and on other factors. The medications that transplant recipients need to take can impair liver function, and transfusionassociated hemosiderosis can do so as well. 40% to 50% of patients suffer from lipid metabolic disturbances that increase the risk of myocardial infarction, peripheral arterial occlusive disease, and stroke. Their life expectancy is shorter than that of the overall population.

Conclusion: Measures should be taken to prevent the potential long-term complications of allo-HSCT. All patients who have been treated with allo-HSCT should receive individualized, risk-adapted, and multidisciplinary follow-up care, so that any complications that arise can be correctly diagnosed and appropriately treated. Long-term follow-up care could be improved by prospective clinical trials investigating the long-term sequelae of allo-HSCT, as well as by consistent, uniform documentation of these sequelae in supraregional data registries.