title: Dosimetric comparison of different treatment planning techniques with International Commission on Radiation Units and Measurements Report-83 recommendations in adjuvant pelvic radiotherapy of gynecological malignancies.
abstract: OBJECTIVE
  The study evaluates the different treatment planning techniques according to three recommendation levels of the International Commission on Radiation Units and Measurements Report-83 in gynecologic cancer patients treated with adjuvant pelvic radiotherapy (APR).
  
  
  METHODS
  Computerized tomography images of ten endometrial and cervical cancer patients who were treated with APR were assessed. For each patient, five different treatment plans were created. One homogeneity index and four different conformity indexes (CIs) were calculated for three-dimensional conformal radiotherapy (3D-CRT), field-in-field (FIF), seven-field intensity modulated radiotherapy (7-IMRT) with two different degrees beginning (7A-IMRT, 7B-IMRT) and 9-IMRT treatment plans. Dose volume histogram parameters and normal tissue complication probability (NTCP) were compared for organs at risk (OAR).
  
  
  RESULTS
  The CI values of the IMRT were closer to 1 with respect to other plans (P < 0.05). The rectum and the bladder volumes which received more than 40 Gy were decreased with IMRT compared to 3D-CRT (P < 0.05). Doses received by the 195 cc volume of the small intestine and NTCP values were significantly decreased with IMRT (P < 0.05).
  
  
  CONCLUSIONS
  IMRT provided more protection than FIF plans at high dose volumes of the OAR; however, it did not show any superiority at low-dose volumes. The NTCP results supported IMRT for only small intestine protection. Because IMRT is increasingly used clinically, the comparison of NTCP will become more common in the near future. Therefore, new prospective studies with sufficient number of patients and appropriate NTCP models are needed for this treatment modality.
authors.affiliation: Department of Radiation Oncology, Antalya Education and Research Hospital, Antalya, Turkey.
authors.forename: Evrim
authors.initials: E
authors.lastname: Duman
authors.affiliation: Department of Radiation Oncology, Antalya Education and Research Hospital, Antalya, Turkey.
authors.forename: Aysun
authors.initials: A
authors.lastname: Inal
authors.affiliation: Department of Radiation Oncology, Antalya Education and Research Hospital, Antalya, Turkey.
authors.forename: Aycan
authors.initials: A
authors.lastname: Sengul
authors.affiliation: Department of Radiation Oncology, Antalya Education and Research Hospital, Antalya, Turkey.
authors.forename: Timur
authors.initials: T
authors.lastname: Koca
authors.affiliation: Department of Radiation Oncology, Akdeniz University School of Medicine, Antalya, Turkey.
authors.forename: Yigit
authors.initials: Y
authors.lastname: Cecen
authors.affiliation: Department of Radiation Oncology, Akdeniz University School of Medicine, Antalya, Turkey.
authors.forename: Melek Nur
authors.initials: MN
authors.lastname: Yavuz
mesh_terms: D003198:Computer Simulation; D005260:Female; D006801:Humans; D009367:Neoplasm Staging; D058958:Organs at Risk; D010386:Pelvic Neoplasms / Q000175:diagnosis / Q000532:radiotherapy*; D011874:Radiometry; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D014057:Tomography, X-Ray Computed