title: A comparison of treatment plans using linac-based intensity-modulated radiation therapy and helical tomotherapy for maxillary sinus carcinoma.
abstract: This study evaluated whether helical tomotherapy (TOMO) planning could achieve better isodose distribution for the maxillary sinus while concomitantly sparing the adjacent _critical normal organs than linac-based step-and-shoot IMRT (s-IMRT) planning. TOMO and s-IMRT were established for 10 patients with maxillary sinus cancer. The prescription (66 Gy, 30 fractions) was used to cover the planning target volume (PTV) with a 95% isodose line. Each plan was independently optimized using the CORVUS planning system and Tomotherapy Hi-Art system. The treatment plans were compared using dose volume histogram (DVH), a dose homogeneity index (DHI) of the PTV, and equivalent uniform dose (EUD) and DVH of organs at risk (OARs). The TOMO plans demonstrated better dose homogeneity compared to the s-IMRT plans. The average V95% of the TOMO plans was similar to that of the s-IMRT (92.92% vs. 95.07%, respectively), but the average V107% was 0% for TOMO compared with 18.74% for s-IMRT. The average maximum dose reduction was 7 Gy, and DHI increased by 8% for PTV1 in TOMO compared with s-IMRT (79 Gy vs. 71 Gy and, 89% vs. 97%, respectively). The average EUD reduction for the optic nerve was 17%. In summary, planning with TOMO was superior to s-IMRT planning with respect to dose homogeneity within the PTV and sparing of the optic nerve.
authors: Department of Radiation Oncology, Yonsei University Health System, Seoul, Korea.
authors: Songyih
authors: S
authors: Kim
authors: Ik  Jae
authors: I
authors: Lee
authors: Yong Bae
authors: YB
authors: Kim
authors: Woong Sub
authors: WS
authors: Koom
authors: Byeong Chul
authors: BC
authors: Jeon
authors: Chang Geol
authors: CG
authors: Lee
authors: Gwi Eon
authors: GE
authors: Kim
authors: Ki Chang
authors: KC
authors: Keum
mesh_terms: D000328:Adult; D000368:Aged; D001933:Brain Stem / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008444:Maxillary Sinus Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D008875:Middle Aged; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D036542:Tomography, Spiral Computed / Q000379:methods*; D014795:Visual Pathways / Q000473:pathology