title: Comparison of dosimetric parameters and acute toxicity after whole-pelvic vs prostate-only volumetric-modulated arc therapy with daily image guidance for prostate cancer.
abstract: OBJECTIVE
  To compare dosimetric parameters and acute toxicity rates between whole-pelvic (WP) and prostate-only (PO) volumetric-modulated arc therapy (VMAT) in patients with localized prostate cancer.
  
  
  METHODS
  A total of 224 consecutive patients treated with definitive VMAT to 78 Gy in 39 fractions were enrolled. Of these, 119 patients received initial WP VMAT at 46.8 Gy in 26 fractions using a simultaneous integrated boost technique, and 105 patients received PO VMAT. Image-guided radiotherapy was practised with daily cone beam CT.
  
  
  RESULTS
  The mean rectal dose, the rectal volume receiving ≥30 Gy (V30Gy), rectal V50Gy, the mean bladder dose, bladder V30Gy and bladder V50Gy were significantly increased in the WP group (p < 0.05 each); however, the rectal V70Gy did not differ between groups (p = 0.101), and the bladder V70Gy was significantly lower in the WP group (p = 0.029). The WP group experienced a significantly increased frequency of acute grade 2 diarrhoea relative to the PO group (5.9% vs 0%; p = 0.015). No differences were seen between the WP and PO groups in terms of acute grade 2 proctitis (10.1% vs 6.7%; p = 0.360) and genitourinary (GU) toxicity (12.6% vs 10.5%; p = 0.620).
  
  
  CONCLUSIONS
  Despite larger rectum and bladder volumes at low- and medium-dose levels, WP VMAT resulted in no significant increase in acute proctitis or GU toxicity when compared with PO VMAT.
  
  
  CONCLUSIONS
  This study demonstrates that whole-pelvic radiotherapy has comparable acute toxicity to those observed with prostate-only radiotherapy when VMAT with daily image guidance is used.
authors.affiliation: 1 Department of Radiation Oncology, Tane General Hospital, Osaka, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ishii
authors.affiliation: 1 Department of Radiation Oncology, Tane General Hospital, Osaka, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Ogino
authors.affiliation: 2 Department of Urology, Tane General Hospital, Osaka, Japan.
authors.forename: Yukinari
authors.initials: Y
authors.lastname: Hosokawa
authors.affiliation: 1 Department of Radiation Oncology, Tane General Hospital, Osaka, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Fujioka
authors.affiliation: 1 Department of Radiation Oncology, Tane General Hospital, Osaka, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Okada
authors.affiliation: 1 Department of Radiation Oncology, Tane General Hospital, Osaka, Japan.
authors.forename: Ryota
authors.initials: R
authors.lastname: Nakahara
authors.affiliation: 1 Department of Radiation Oncology, Tane General Hospital, Osaka, Japan.
authors.forename: Ryu
authors.initials: R
authors.lastname: Kawamorita
authors.affiliation: 3 Department of Radiology, Izumi Municipal Hospital, Osaka, Japan.
authors.forename: Takuhito
authors.initials: T
authors.lastname: Tada
authors.affiliation: 2 Department of Urology, Tane General Hospital, Osaka, Japan.
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Hayashi
authors.affiliation: 1 Department of Radiation Oncology, Tane General Hospital, Osaka, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Nakajima
mesh_terms: D000368:Aged; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D059351:Organ Sparing Treatments / Q000706:statistics & numerical data; D010388:Pelvis / Q000528:radiation effects; D015995:Prevalence; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000532:radiotherapy*; D000069079:Radiation Exposure / Q000706:statistics & numerical data*; D011832:Radiation Injuries / Q000453:epidemiology*; D011879:Radiotherapy Dosage; D061089:Radiotherapy, Image-Guided / Q000706:statistics & numerical data*; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods / Q000706:statistics & numerical data*; D012307:Risk Factors; D016896:Treatment Outcome