A comparison of late mortality among survivors of childhood cancer in the United States and United Kingdom
Menée à partir des données d'une cohorte américaine et d'une cohorte britannique incluant respectivement 31 596 et 18 226 patients ayant survécu à un cancer pédiatrique diagnostiqué avant l'âge de 15 ans sur la période 1970-1999, cette étude analyse les facteurs associés au risque de décès et les causes de mortalité
Background : It is unclear whether late effect risks among childhood cancer survivors vary internationally. We compared late mortality in the North American Childhood Cancer Survivor Study (CCSS) and British Childhood Cancer Survivor Study (BCCSS).
Methods : Late mortality was assessed among 49,822 5-year survivors of childhood cancer diagnosed before 15 years of age from 1970-1999 (CCSS n = 31,596; BCCSS n = 18,226) using cumulative mortality probabilities and adjusted ratios of the standardized mortality ratio (RSMR).
Results : The all-cause cumulative mortality probability at 10 years from diagnosis was statistically significantly lower in the CCSS (4.7%; 95%CI= 4.5%-5.0%) compared to the BCCSS (6.9%; 95%CI= 6.5%-7.2%), attributable to a lower probability of death from recurrence/progression of the primary cancer, with statistically significant differences observed in survivors of leukemia, lymphoma, central nervous system tumors, and sarcoma. However, at 40 years from diagnosis the CCSS had a greater cumulative mortality probability (22.3% vs. 19.3%), attributable to a 2-fold higher risk of mortality from subsequent malignant neoplasms, cardiac and respiratory diseases, and other health-related causes. Differences increased when assessed by follow-up interval, with the CCSS faring worse as time since diagnosis increased. Finally, the gap in all-cause mortality widened more recently, with CCSS survivors diagnosed in 1990-1999 experiencing half the excess deaths observed in the BCCSS (RSMR=0.5; 95%CI= 0.5-0.6).
Conclusions : Our findings suggest that US survivors may have received more intensive regimens to achieve sustainable remission and cure, but the cost of this approach was a higher risk of death from late effects. While the clinical impact of these differences is unclear, our results provide important evidence to aid the discussion of late effects management.
Journal of the National Cancer Institute , résumé, 2019