Impact of era of diagnosis on cause-specific late mortality among 77 423 five-year European survivors of childhood and adolescent cancer: The PanCareSurFup consortium.

Abstract

Late mortality of European 5-year survivors of childhood or adolescent cancer has dropped over the last 60 years, but excess mortality persists. There is little information concerning secular trends in cause-specific mortality among older European survivors. PanCareSurFup pooled data from 12 cancer registries and clinics in 11 European countries from 77 423 five-year survivors of cancer diagnosed before age 21 between 1940 and 2008 followed for an average age of 21 years and a total of 1.27 million person-years to determine their risk of death using cumulative mortality, standardized mortality ratios (SMR), absolute excess risks (AER), and multivariable proportional hazards regression analyses. At the end of follow-up 9166 survivors (11.8%) had died compared to 927 expected (SMR 9.89, 95% confidence interval [95% CI] 9.69-10.09), AER 6.47 per 1000 person-years, (95% CI 6.32-6.62). At 60 to 68 years of attained age all-cause mortality was still higher than expected (SMR=2.41, 95% CI 1.90-3.02). Overall cumulative mortality at 25 years from diagnosis dropped from 18.4% (95% CI 16.5-20.4) to 7.3% (95% CI 6.7-8.0) over the observation period. Compared to the diagnosis period 1960 to 1969, the mortality hazard ratio declined for first neoplasms (P for trend <.0001) and for infections (P < .0001); declines in relative mortality from second neoplasms and cardiovascular causes were less pronounced (P=.1105 and P=.0829, respectively). PanCareSurFup is the largest study with the longest follow-up of late mortality among European childhood and adolescent cancer 5-year survivors, and documents significant mortality declines among European survivors into modern eras. However, continuing excess mortality highlights survivors' long-term care needs.