title: [Stereotactic body radiation therapy: uncertainties and margins].
abstract: The principles governing stereotactic body radiation therapy are tight margins and large dose gradients around targets. Every step of treatment preparation and delivery must be evaluated before applying this technique in the clinic. Uncertainties remain in each of these steps: delineation, prescription with the biological equivalent dose, treatment planning, patient set-up taking into account movements, the machine accuracy. The calculation of margins to take into account uncertainties differs from conventional radiotherapy because of the delivery of few fractions and large dose gradients around the target. The quest of high accuracy is complicated by the difficulty to reach it and the lack of consensus regarding the prescription. Many schemes dose/number of fractions are described in clinical studies and there are differences in the way describing the delivered doses. While waiting for the ICRU report dedicated to this technique, it seems desirable to use the quantities proposed in ICRU Report 83 (IMRT) to report the dose distribution.
authors.affiliation: Service de physique médicale, centre Oscar-Lambret, 3, rue Frédéric-Combemale, 59020 Lille, France. Electronic address: t-lacornerie@o-lambret.fr.
authors.forename: T
authors.initials: T
authors.lastname: Lacornerie
authors.affiliation: Unité de physique médicale, institut de cancérologie de Lorraine Alexis-Vautrin, avenue de Bourgogne, 54519 Vandœuvre-lès-Nancy, France.
authors.forename: V
authors.initials: V
authors.lastname: Marchesi
authors.affiliation: Service de physique médicale, centre Oscar-Lambret, 3, rue Frédéric-Combemale, 59020 Lille, France.
authors.forename: N
authors.initials: N
authors.lastname: Reynaert
mesh_terms: D000465:Algorithms; D006801:Humans; D064847:Multimodal Imaging; D009369:Neoplasms / Q000473:pathology / Q000601:surgery*; D056888:Patient Positioning; D017410:Practice Guidelines as Topic; D016634:Radiosurgery / Q000379:methods*; D011879:Radiotherapy Dosage; D061089:Radiotherapy, Image-Guided
keywords: Contrôle de qualité; Extracrânien; Incertitudes; Quality assurance; Radiothérapie stéréotaxique; Stereotactic body radiation therapy; Uncertainties