title: Whole-pelvic volumetric-modulated arc therapy for high-risk prostate cancer: treatment planning and acute toxicity.
abstract: The objectives of this study were to evaluate dosimetric quality and acute toxicity of volumetric-modulated arc therapy (VMAT) and daily image guidance in high-risk prostate cancer patients. A total of 100 consecutive high-risk prostate cancer patients treated with definitive VMAT with prophylactic whole-pelvic radiotherapy (WPRT) were enrolled. All patients were treated with a double-arc VMAT plan delivering 52 Gy to the prostate planning target volume (PTV), while simultaneously delivering 46.8 Gy to the pelvic nodal PTV in 26 fractions, followed by a single-arc VMAT plan delivering 26 Gy to the prostate PTV in 13 fractions. Image-guided RT was performed with daily cone-beam computed tomography. Dose-volume parameters for the PTV and the organs at risk (OARs), total number of monitor units (MUs) and treatment time were evaluated. Acute toxicity was assessed using the Common Terminology Criteria for Adverse Events, version 4.0. All dosimetric parameters met the present plan acceptance criteria. Mean MU and treatment time were 471 and 146 s for double-arc VMAT, respectively, and were 520 and 76 s for single-arc VMAT, respectively. No Grade 3 or higher acute toxicity was reported. Acute Grade 2 proctitis, diarrhea, and genitourinary toxicity occurred in 12 patients (12%), 6 patients (6%) and 13 patients (13%), respectively. The present study demonstrated that VMAT for WPRT in prostate cancer results in favorable PTV coverage and OAR sparing with short treatment time and an acceptable rate of acute toxicity. These findings support the use of VMAT for delivering WPRT to high-risk prostate cancer patients.
authors.affiliation: Department of Radiation Oncology, Tane General Hospital, 1-12-21 Kujo-minami, Nishi-ku, Osaka, 550-0025, Japan 141kentaro@gmail.com.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ishii
authors.affiliation: Department of Radiation Oncology, Tane General Hospital, 1-12-21 Kujo-minami, Nishi-ku, Osaka, 550-0025, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Ogino
authors.affiliation: Department of Urology, Tane General Hospital, 1-12-21 Kujo-minami, Nishi-ku, Osaka, 550-0025, Japan.
authors.forename: Yukinari
authors.initials: Y
authors.lastname: Hosokawa
authors.affiliation: Department of Radiation Oncology, Tane General Hospital, 1-12-21 Kujo-minami, Nishi-ku, Osaka, 550-0025, Japan.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Fujioka
authors.affiliation: Department of Radiation Oncology, Tane General Hospital, 1-12-21 Kujo-minami, Nishi-ku, Osaka, 550-0025, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Okada
authors.affiliation: Department of Radiation Oncology, Tane General Hospital, 1-12-21 Kujo-minami, Nishi-ku, Osaka, 550-0025, Japan.
authors.forename: Ryota
authors.initials: R
authors.lastname: Nakahara
authors.affiliation: Department of Radiation Oncology, Tane General Hospital, 1-12-21 Kujo-minami, Nishi-ku, Osaka, 550-0025, Japan.
authors.forename: Ryu
authors.initials: R
authors.lastname: Kawamorita
authors.affiliation: Department of Radiology, Izumi Municipal Hospital, 4-10-10 Futyu-cho, Izumi, 594-0071, Japan.
authors.forename: Takuhito
authors.initials: T
authors.lastname: Tada
authors.affiliation: Department of Urology, Tane General Hospital, 1-12-21 Kujo-minami, Nishi-ku, Osaka, 550-0025, Japan.
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Hayashi
authors.affiliation: Department of Radiation Oncology, Tane General Hospital, 1-12-21 Kujo-minami, Nishi-ku, Osaka, 550-0025, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Nakajima
mesh_terms: D000368:Aged; D015897:Comorbidity; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D059351:Organ Sparing Treatments / Q000379:methods / Q000706:statistics & numerical data; D058958:Organs at Risk / Q000528:radiation effects; D010388:Pelvis; D015995:Prevalence; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000453:epidemiology* / Q000209:etiology; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated; D012307:Risk Factors; D016896:Treatment Outcome
keywords: acute toxicity; image-guided radiotherapy; prostate cancer; treatment planning; volumetric-modulated arc therapy; whole-pelvic radiotherapy