Incident cancers and late mortality in Australian children treated by allogeneic stem cell transplantation for non-malignant diseases.

Abstract

Hematopoietic stem cell transplantation (HSCT) is a life-saving procedure for children with a variety of non-malignant conditions. However, these children face an increased risk of late death and incident cancers after HSCT, which may occur many years after their initial HSCT. We examined cancer occurrence and late mortality in a population-based cohort of 318 Australian children who underwent allogeneic HSCT for non-malignant disease. Standardized incident ratios (SIRs) and standardized mortality ratios (SMRs) were calculated and compared with population controls. We identified six (1.9%) cancers at a median 9.2 years post-HSCT. Cancer occurred 15 times more frequently than in the general population (SIR 15.4, 95% CI = 6.9-34.2). Of the 198 patients who survived for at least 2 years post-HSCT, 11 (5.6%) died at a median 7.5 years post-HSCT. The mortality rate was 17 times higher than in the general population (SMR 17.5, 95% CI = 9.7-31.2). Children transplanted for non-malignant conditions require evidence-based survivorship programs to reduce excess morbidity and mortality.