Effects of field parameters on IMRT plan quality for gynecological cancer: A case study

• DOI: 10.1120/jacmp.v6i3.2087
• Publication Date: 2008-12-10T19:02:15Z
• Authors: Albert Y.C. Fung; Charles A. Enke; Komanduri M. Ayya...; Robert B. Thompson; Weining Zhen; Natarajan V. Raman; David Djajaputra; Sicong Li; Ramasamy M. Nehru; Sushakumari Pillai; Paul Sourivong; Mary Headley; Ann L. Yager
• Keywords: Collimator; Multileaf collimator

Traditional external beam radiotherapy of gynecological cancer consists a 3D, four-field-box technique. The radiation treatment area is large region normal tissue, with greater inhomogeneity over the volume, which could benefit more intensity-modulated therapy (IMRT). This case report IMRT planning for patient endometrial cancer. target volume (PTV) spanned intrapelvic and periaortic lymph nodes to 33-cm length. Planning were accomplished using double isocenters. plan was compared 3D plan, effects field parameters studied. Delineated anatomical contours included (PTV), bone marrow, small bowel, bladder, rectum, sigmoid colon, spinal cord, left kidney, right liver, tissue (excluding PTVs). Comparisons made between plans, 23-MV 6-MV energies, zero rotated collimator angles, different numbers segments, opposite gantry angle configurations. plans evaluated based on dose-volume histograms (DVHs). Compared had superior dose conformity spared bladder colon embedded in nodes. higher energy (23 MV) reduced most critical organs delivered less integral dose. Zero angles resulted better than “optimized” lower structures. number segments did not have much effect isodose distribution, but reasonable necessary keep time from being prohibitively long. Gantry when evenly spaced, no noticeable plan. tolerated well, initial complete blood count favorable. Our results indicated that large-volume tumor sites may also precise conformal delivery IMRT. PACS numbers: 87.53.Kn, 87.53.Tf