title: [Intensity modulated radiotherapy with dynamic multileaf collimator. Technique and clinical experience].
abstract: Since early 1997, dynamic multileaf collimators (DMLCs) have been used in our division for intensity modulated radiotherapy (IMRT). We have used IMRT to: irradiate concave targets (head and neck, paraspinal tumors); combine beams with shallow hinge angles (mediastinum, lung tumors); deliver intentionally inhomogeneous dose distributions (prostate, paranasal sinuses, brain tumors). IMRT is now our standard treatment for locoregional relapse (after high-dose radiotherapy) for head and neck cancer and for radical treatment of localized prostate cancer. For a variety of other tumors, conventional 3D-plans are compared with IMRT-plans, the latter being clinically implemented if superior. We developed a geometry based IMRT planning strategy to create assemblies of static intensity modulated (IM)-beams which consist of uniform (unmodulated) segments. By a translator program, segments are combined in a single prescription which allows delivery under computer control. Cost-containment is further improved by automation of the planning. After manual or semi-automated contouring of PTV and the organs at risk, prostate IMRT plans, based on a class solution, are generated and optimized by a computer. IMRT for pharyngeal relapses and most other tumor sites is planned semi-automatically. IMRT replaces gradually conventional treatments in our division. Interesting dose distributions generated by IMRT allow a better sparing of normal tissues with decreased acute and late toxicity, and offer a window for further dose escalation.
authors.affiliation: Département de radiothérapie et de médecine nucléaire, Hôpital universitaire de Gand (R-UZG), Belgique.
authors.forename: W
authors.initials: W
authors.lastname: De Neve
authors.forename: F
authors.initials: F
authors.lastname: Claus
authors.forename: P
authors.initials: P
authors.lastname: Van Houtte
authors.forename: S
authors.initials: S
authors.lastname: Derycke
authors.forename: C
authors.initials: C
authors.lastname: De Wagter
mesh_terms: D000465:Algorithms; D001932:Brain Neoplasms / Q000532:radiotherapy; D002648:Child; D003363:Cost Control; D005260:Female; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008175:Lung Neoplasms / Q000532:radiotherapy; D008297:Male; D008479:Mediastinal Neoplasms / Q000532:radiotherapy; D008875:Middle Aged; D008962:Models, Theoretical; D009364:Neoplasm Recurrence, Local / Q000532:radiotherapy*; D011471:Prostatic Neoplasms / Q000532:radiotherapy; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000295:instrumentation / Q000379:methods; D020266:Radiotherapy, Conformal / Q000191:economics / Q000295:instrumentation