title: The impact of prostate gland dimension in genitourinary toxicity after definitive prostate cancer treatment with moderate hypofractionation and volumetric modulated arc radiation therapy.
abstract: OBJECTIVE
  To analyze clinical-dosimetric predictors of genitourinary (GU) toxicity in a cohort of prostate cancer (PC) patients treated with moderate hypofractionation and simultaneous integrated boost (SIB) using volumetric modulated arc therapy (VMAT) technique.
  
  
  METHODS
  60 patients were selected. Patients were stratified into low (43 %), intermediate (30 %) and high-risk (27 %) groups. Low-risk patients received 73.5 Gy to PTV1; intermediate-risk received 73.5 Gy to PTV1 and 60 Gy to PTV2; high-risk received 73.5 Gy to PTV1, 60 Gy to PTV2, and 54 Gy to PTV3. All patients were treated in 30 fractions. Androgen deprivation therapy (ADT) was prescribed upfront in intermediate and high-risk categories. Toxicity was scored according to Common Terminology Criteria for Adverse Events v4.0 scoring system.
  
  
  RESULTS
  Median follow-up was 30 months (range 16-36 months). GU acute toxicity was recorded as followS: G0 = 16/60 (27 %), G1 = 18/60 (30 %); G2 = 26/60 (43 %). GU late toxicity was recorded as follows: G0 = 20/60 (34 %); G1 = 29/60 (48 %); G2 = 11/56 (18 %). The risk of acute G2 GU toxicity was three times higher for prostate volume ≥80 cc. In 60 % of the patients with a prostate volume ≥80 cc, the first 3 weeks are at particular risk for toxicity onset. In the late setting, no statistical significance was found between GU toxicity and prostate gland dimension.
  
  
  CONCLUSIONS
  Prostate volume ≥80 cc resulted a predictive factor of acute G2 GU toxicity, in moderate hypofractionation and volumetric modulated arc radiation therapy for definitive PC.
authors.affiliation: Radiation Oncology, Sacro Cuore Don Calabria Hospital, Negrar-Verona, Italy.|Radiation Oncology School, University of Palermo, Palermo, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Mazzola
authors.affiliation: Radiation Oncology, Sacro Cuore Don Calabria Hospital, Negrar-Verona, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Fersino
authors.affiliation: Radiation Oncology, Sacro Cuore Don Calabria Hospital, Negrar-Verona, Italy. albafiorentino@hotmail.it.
authors.forename: A
authors.initials: A
authors.lastname: Fiorentino
authors.affiliation: Radiation Oncology, Sacro Cuore Don Calabria Hospital, Negrar-Verona, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Ricchetti
authors.affiliation: Radiation Oncology, Sacro Cuore Don Calabria Hospital, Negrar-Verona, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Giaj Levra
authors.affiliation: Statistic Sciences Faculty, University of Palermo, Palermo, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Di Paola
authors.affiliation: Radiation Oncology, Sacro Cuore Don Calabria Hospital, Negrar-Verona, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Sicignano
authors.affiliation: Radiation Oncology, Sacro Cuore Don Calabria Hospital, Negrar-Verona, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Naccarato
authors.affiliation: Radiation Oncology, Sacro Cuore Don Calabria Hospital, Negrar-Verona, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Ruggieri
authors.affiliation: Radiation Oncology, Sacro Cuore Don Calabria Hospital, Negrar-Verona, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Alongi
mesh_terms: D000230:Adenocarcinoma / Q000532:radiotherapy*; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D058958:Organs at Risk / Q000528:radiation effects*; D011467:Prostate; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D000069473:Radiation Dose Hypofractionation; D011832:Radiation Injuries / Q000209:etiology; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects*; D014566:Urogenital System / Q000528:radiation effects*
keywords: Hypofractionation; Prostate cancer; Radiotherapy; Toxicity