Risk of symptomatic stroke after radiotherapy for childhood cancer: a long-term follow-up cohort analysis
Menée sur une cohorte de 1 362 patients atteints d'un cancer durant l'enfance et traités par radiothérapie crânienne ou sus-diaphragmatique, cette étude évalue le risque d'accident vasculaire cérébral symptomatique à l'âge adulte
Purpose : Long-term childhood cancer survivors are at high risk of late adverse effects, including stroke. We aimed to determine the cumulative incidence of clinically validated symptomatic stroke (transient ischemic attack (TIA), cerebral infarction and intracerebral hemorrhage (ICH)), and to quantify dose-effect relationships for cranial radiotherapy (CRT) and supradiaphragmatic radiotherapy (SDRT). Methods and Materials : Our single-center study cohort included 1362 childhood cancer survivors diagnosed between 1966-1996. Prescribed CRT and SDRT doses were converted into the equivalent dose in 2-Gy fractions (EQD2). Multivariate Cox regression models were used to analyze the relationship between the EQD2 and stroke. Results : After a median latency time of 24.9 years and at a median age of 31.2 years, 28 survivors had experienced a first stroke (TIA (5); infarction (13); ICH (10)). At an attained age of 45 years, the estimated cumulative incidences, with death as competing risk, among survivors treated with CRT only, SDRT only, both CRT and SDRT, and neither CRT nor SDRT were respectively 10.0% (95%CI, 2.5-17.0%), 5.4% (95%CI, 0-17.0%), 12.5% (95%CI, 5.5-18.9%), and 0.1% (95%CI, 0-0.4%). Radiation at both locations significantly increased the risk of stroke in a dose-dependent manner (HRCRT 1.02 Gy-1; 95%CI, 1.01-1.03, and HRSDRT 1.04 Gy-1; 95%CI, 1.02-1.05). Conclusions : Childhood cancer survivors treated with CRT and/or SDRT have a high stroke risk. One in 8 survivors treated at both locations will have experienced a symptomatic stroke at an attained age of 45 years. Further research on the pathophysiological processes involved in stroke in this specific group of patients is needed to develop tailored secondary prevention strategies.
http://www.redjournal.org/article/S0360-3016%2816%2930039-6/abstract 2016