New evidence for brain cancer risk after a single paediatric CT scan
Menée à partir de données européennes 1977-2014 portant sur 658 752 personnes ayant réalisé au moins un examen tomodensitométrique avant l'âge de 22 ans (56 % d'hommes ; durée médiane de suivi : 5,6 ans), cette étude multicentrique analyse l'association entre la quantité de rayonnements reçus chez l'enfant ou le jeune adulte et le risque de cancer du cerveau (165 cas dont 121 gliomes)
Résumé en anglais
Despite the unquestionable benefits of diagnostic radiation exposure, the potential health risks are of considerable concern, particularly for the risk of brain cancer following paediatric head CT examinations. In The Lancet Oncology, Michael Hauptmann and colleagues present the results of a large-scale study from nine European countries (the EPI-CT cohort study) to quantify the risks of brain cancer in more than 650 000 patients who had a first head or neck CT examination when they were younger than 22 years. The mean estimated cumulative brain absorbed dose, lagged by 5 years, was 47·4 mGy (SD 60·9). About three quarters of the observed brain cancers were of glioma type (121 [73%] of 165 cases), which is typically a rapidly progressing tumour in adults. Hauptmann and colleagues estimated significant linear dose-response relationships for all brain cancers and for glioma, with excess relative risk estimates per 100 mGy of 5-year lagged cumulative brain dose of 1·27 (95% CI 0·51–2·69) for all brain cancers and 1·11 (0·36–2·59) for gliomas. Risk estimates remained significantly elevated when the analysis included doses only up to 50 mGy or patients who only received a single CT examination. The authors inferred that, per 10 000 people receiving a single head CT examination (giving an average brain dose of 38 mGy), about one radiation-induced brain cancer is expected 5–15 years after the CT examination.
