title: Vaginal dose point reporting in cervical cancer patients treated with combined 2D/3D external beam radiotherapy and 2D/3D brachytherapy.
abstract: OBJECTIVE
  Traditionally, vaginal dose points have been defined at the vaginal source level, thus not providing dose information for the entire vagina. Since reliable vaginal dose volume/surface histograms are unavailable, a strategy for comprehensive vaginal dose reporting for combined EBRT and BT was established and investigated.
  
  
  METHODS
  An anatomical vaginal reference point was defined at the level of the Posterior-Inferior Border of Symphysis (PIBS), plus two points ±2 cm (mid/introitus vagina). For BT extra points were selected for the upper vagina at 12/3/6/9 o'clock, at the vaginal surface and 5 mm depth. A vaginal reference length (VRL) was defined from ring centre to PIBS. Fifty-nine patients treated for cervical cancer were included in this retrospective feasibility study.
  
  
  RESULTS
  The method was applicable to all patients. Total EQD2 doses at PIBS and ±2 cm were 36.7 Gy (3.1-68.2), 49.6 Gy (32.1-89.6) and 4.3 Gy (1.0-46.6). At the vaginal surface at ring level doses were respectively 266.1 Gy (67.6-814.5)/225.9 Gy (61.5-610.5) at 3/9 o'clock, and 85.1 Gy (55.4-140.3)/72.0 Gy (49.1-108.9) at 12/6 o'clock. Mean VRL on MRI was 5.6 cm (2.0-9.4).
  
  
  CONCLUSIONS
  With this novel system, a comprehensive reporting of vaginal doses is feasible. The present study has demonstrated large dose variations between patients observed in all parts of the vagina, resulting from different contributions from EBRT and BT.
authors: Department of Radiotherapy, Comprehensive Cancer Center, Medical University of Vienna, Austria. g.h.westerveld@amc.uva.nl
authors: Henrike
authors: H
authors: Westerveld
authors: Richard
authors: R
authors: Pötter
authors: Daniel
authors: D
authors: Berger
authors: Pittaya
authors: P
authors: Dankulchai
authors: Wolfgang
authors: W
authors: Dörr
authors: Mircea-Constantin
authors: MC
authors: Sora
authors: Sarah
authors: S
authors: Pötter-Lang
authors: Christian
authors: C
authors: Kirisits
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000379:methods*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D002583:Uterine Cervical Neoplasms / Q000532:radiotherapy*; D014621:Vagina / Q000528:radiation effects*