Etude Des séquelles Neurocognitives à Long Terme Des Faibles Doses de Radiation Chez 150 Patients traités Par radiothérapie Dans l'Enfance Pour un hémangiome cutané à l'Institut Gustave Roussy (IGR) Entre 1941 et 1973

Context: Studies that address specifically the neurocognitive consequences that can be caused by low-dose radiation receiving during the childhood have still to be performed. In this issue, we focus on an investigation with patients who have received radiotherapy for a benign tumor (skin hemangioma), in France.

Patients and methods: More than 8300 children with a skin hemangioma were treated at Gustave Roussy (Île-de-France) from 1941 to 1973 and a number of them have received radiotherapy. These patients have been treated and followed by Gustave Roussy, so their clinical records can be tracked with great accuracy and the ionizing radiation dose to the brain have been estimated. From this patient cohort, the aim is to evaluate neurocognitive dysfunction or disorder that can be caused by low-dose radiation to the brain (less than one Gray (Gy)). A total of 150 patients is expected. They will be contacted by letter to explain the purpose and methods of carrying out tests. Two groups will be analysed according to the received ionizing radiation dose to the brain during the radiotherapy (exposed: 0.05 to 1 Gy, vs unexposed: less than 0.05 Gy). Tests exploring several cognitive functions (memory, arithmetic, orientation, etc.) will be used.

Expected results: We expect to describe the potential neurocognitive dysfunction or disorder and to identify risk factors and brain structures whose lesions are responsible for the neurocognitive dysfunction or disorder.

A therapeutic treatment will be proposed in the eventuality of screening of a neurocognitive dysfunction or disorder.