title: Electron-photon field matching in the treatment of paranasal sinus tumors: a case report.
abstract: The treatment planning of paranasal sinus tumors is technically demanding due to the compact anatomy of the region and the close proximity of critical structures. In the majority of cases, conventional approaches utilizing 2 or 3 photon fields are adequate. However, in patients with locally advanced disease, these standard techniques may result in the unnecessary treatment of surrounding structures. We present here a case in which, because of the complex tumor geometry, conventional techniques would result in treating through both orbits. A novel treatment approach has been devised in which opposed lateral photon fields are matched to an anterior electron field (both in depth and in profile) to provide a uniform dose distribution to the target volume, while minimizing the dose to certain critical structures. The treatment design, in particular the methodology of electron-photon field matching as well as the specification of tissue compensation and customized blocking, is discussed.
authors.affiliation: Department of Radiation and Cellular Oncology, University of Chicago, Illinois 60637, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Roeske
authors.forename: F T
authors.initials: FT
authors.lastname: Kuchnir
authors.forename: A J
authors.initials: AJ
authors.lastname: Mundt
authors.forename: D J
authors.initials: DJ
authors.lastname: Haraf
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D008297:Male; D008579:Meningioma / Q000000981:diagnostic imaging / Q000532:radiotherapy* / Q000556:secondary*; D010255:Paranasal Sinus Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy* / Q000556:secondary*; D011879:Radiotherapy Dosage; D011881:Radiotherapy, Computer-Assisted; D011882:Radiotherapy, High-Energy / Q000379:methods*; D014057:Tomography, X-Ray Computed