title: Hyperfractionated, twice-a-day, radiotherapy may decrease IQ deterioration due to prophylactic cranial irradiation in childhood acute lymphoblastic leukemia: a radiobiological analysis.
abstract: High cure rates in childhood acute lymphoblastic leukemia (ALL) are being achieved with aggressive systemic chemotherapy and treatment to sanctuary sites including prophylactic cranial irradiation. However, IQ deterioration is a dreaded complication of prophylactic cranial irradiation. IQ deterioration is a late sequela. Since there is evidence--both radiobiological and clinical--to suggest that acute tissue (including tumor) response and late tissue response can be separated by hyper-fractionation, we propose a twice-a-day radiotherapy in prophylactic cranial irradiation of childhood ALL to decrease delayed toxicity. Analysis based on current radiobiological models favors such a treatment scheme. However, only a prospective clinical trial can confirm whether IQ deterioration can be prevented or decreased with hyper-fractionated radiotherapy.
authors.affiliation: Department of Radiation and Cellular Oncology, Michael Reese/University of Chicago, IL 60616.
authors.forename: S
authors.initials: S
authors.lastname: Vijayakumar
authors.forename: R
authors.initials: R
authors.lastname: Muller-Runkel
mesh_terms: D001932:Brain Neoplasms / Q000517:prevention & control / Q000556:secondary*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002648:Child; D004307:Dose-Response Relationship, Radiation; D005500:Follow-Up Studies; D006801:Humans; D007360:Intelligence / Q000528:radiation effects*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000532:radiotherapy*; D011878:Radiotherapy / Q000379:methods*; D011879:Radiotherapy Dosage; D013997:Time Factors