Morbidity and Mortality Differences Between Hematopoietic Cell Transplantation Survivors and Other Cancer Survivors

Abstract

Purpose To compare the risks of serious health outcomes among hematopoietic cell transplantation (HCT) survivors versus a matched population of patients with cancer who did not undergo HCT, where the primary difference may be exposure to HCT. Methods Two-year HCT survivors treated at a comprehensive cancer center from 1992 through 2009 who were Washington State residents (n = 1,792; 52% allogeneic and 90% hematologic malignancies) were frequency matched by demographic characteristics and underlying cancer diagnosis (as applicable) to non-HCT 2-year cancer survivors, using the state cancer registry (n = 5,455) and the general population (n = 16,340) using driver's license files. Late outcomes for all three cohorts were ascertained from the state hospital discharge and death registries; subsequent cancers were ascertained from the state cancer registry. Results After median follow-up of 7.1 years, HCT survivors experienced significantly greater rates of hospitalization compared with matched non-HCT cancer survivors (280 v 173 episodes per 1,000 person-years, P < .001) and greater all-cause mortality (hazard ratio [HR], 1.1; 95% CI, 1.01 to 1.3). HCT survivors had more hospitalizations or death with infections (10-year cumulative incidence, 31% v 22%; HR, 1.4; 95% CI, 1.3 to 1.6) and respiratory complications (cumulative incidence, 27% v 20%; HR, 1.4; 95% CI, 1.2 to 1.5). Risks of digestive, skin, and musculoskeletal complications also were greater among HCT versus non-HCT cancer survivors. The two groups had similar risks of circulatory complications and second cancers. Both HCT and non-HCT cancer survivors had significantly greater 10-year cumulative incidences of all major organ-system outcomes versus the general population. Conclusion History of HCT was associated with late morbidity and mortality among cancer survivors. In particular, clinicians who care for HCT survivors should be aware of their high rates of late respiratory and infectious complications.

Fig 1.

Ten-year cumulative incidence with 95% CIs (spikes) of major outcomes among ≥ 2-year HCT survivors and comparison cohorts (non-HCT cancer survivors; general population, DOL). Incidence of pregnancy was limited to women ages 15 to 44 years during the observation period. Subsequent new cancers were only ascertained among HCT and non-HCT cancer survivors. *P < .05 for differences between HCT v non-HCT. †P <.05 for differences between HCT v DOL and non-HCT v DOL, limited to individuals age ≥ 16 years. ‡P <.05 for difference between HCT v DOL only. DOL, Department of Licensing; HCT, hematopoietic cell transplantation.