title: Computed tomography-based three-dimensional dosimetry of intracavitary brachytherapy for cervical cancer.
abstract: OBJECTIVE
  The aim of this study was to show the results of computed tomography (CT)-based dosimetry of intracavitary brachytherapy for cervical cancer.
  
  
  METHODS
  A total of 20 patients with cervical cancer underwent intracavitary brachytherapy with external beam radiation therapy. The prescribed dose of brachytherapy was 6 Gy per fraction to point A. In every fraction a CT scan was performed after applicator insertion and three-dimensional (3D) dosimetry was done. The tumor dose was evaluated using D90 (the minimum dose delivered to 90% of the volume), and the doses of risk organs were evaluated using D2cc (the minimum dose in the most irradiated 2 cm3 of the volume).
  
  
  RESULTS
  The mean D90 for the clinical target volume (CTV) was 7.0 Gy (range 4.8-9.8 Gy). There was a negative correlation between the volume and the D90 for the CTV. The mean D2cc doses for the rectum and bladder were 6.0 Gy (range 3.9-9.0 Gy) and 6.5 Gy 5 Gy 2.9-9.0 Gy), respectively.
  
  
  CONCLUSIONS
  CT-based 3D dosimetry of intracavitary brachytherapy for cervical cancer was useful for evaluating the doses of the CTV and the organs at risk. In cases with a large CTV, CTV D90 was often lower than the point A dose, and modulation of the prescribed dose might have to be considered.
authors.affiliation: Department of Radiology, Hiroshima Prefectural Hospital, 1-5-54 Ujinakanda, Minami-ku, Hiroshima, 734-8530, Japan. k-wadasaki@hph.pref.hiroshima.jp
authors.forename: Koichi
authors.initials: K
authors.lastname: Wadasaki
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Monzen
authors.forename: Taichi
authors.initials: T
authors.lastname: Kurose
authors.forename: Hajime
authors.initials: H
authors.lastname: Okazaki
authors.forename: Mio
authors.initials: M
authors.lastname: Mito
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000379:methods*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008875:Middle Aged; D011874:Radiometry; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D002583:Uterine Cervical Neoplasms / Q000532:radiotherapy*