title: High-Risk Prostate Cancer and Radiotherapy: The Past and the Future. A Benchmark for a New Mixed Beam Radiotherapy Approach.
abstract: The prognosis for patients with high-risk prostate cancer is poor. No consensus exists on the most effective treatment. The aim of this retrospective study was to identify the biochemical progression-free survival and the toxicity profile of patients with localized high-risk prostate cancer treated with external beam radiation therapy. These results will constitute a benchmark for a prospective "mixed beam" trial: a boost with carbon ions followed by a pelvic photon intensity-modulated radiotherapy (NCT02672449 [clinicaltrials.gov]).
  
  
  
  We retrospectively reviewed the data of 76 patients treated in our institution with photon radiation therapy according to the inclusion criteria of the future "mixed beam" trial: cT3a and/or serum prostate-specific antigen > 20 ng/mL and/or Gleason score of 8 to 10, cN0 cM0. Toxicity, and biochemical and clinical progression-free survival were assessed.
  
  
  
  Seventy-six patients fulfilled our criteria. The median follow-up was 30.2 months (range, 7.2-61.1). Biochemical progression was observed in 22 patients (28.9%) after a median time of 20.2 months (range, 5-58.1) from the end of radiotherapy. Sixteen patients had clinical progression, in all the cases preceded by biochemical progression. Fifty-seven patients (75%) are alive with no evidence of disease, 13 (17.1%) are alive with clinically evident disease, 6 died (3 of prostate disease 3.9%).
  
  
  
  Our results suggest that a more aggressive treatment is necessary. Local treatment intensification based on the "mixed beam" approach combining carbon ions (with its known radiobiological advantages) and photons might represent a promising strategy in high-risk prostate cancer and it will be investigated with our prospective clinical trial.
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy. Electronic address: giulia.marvaso@ieo.it.
authors.forename: Giulia
authors.initials: G
authors.lastname: Marvaso
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy; Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy.
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Jereczek-Fossa
authors.affiliation: Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Riva
authors.affiliation: University of Parma, Parma, Italy.
authors.forename: Camilla
authors.initials: C
authors.lastname: Bassi
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: Cristiana
authors.initials: C
authors.lastname: Fodor
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: Delia
authors.initials: D
authors.lastname: Ciardo
authors.affiliation: Department of Medical Physics, European Institute of Oncology, Milan, Italy.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Cambria
authors.affiliation: Department of Medical Physics, European Institute of Oncology, Milan, Italy.
authors.forename: Floriana
authors.initials: F
authors.lastname: Pansini
authors.affiliation: Department of Radiotherapy, European Institute of Oncology, Milan, Italy.
authors.forename: Dario
authors.initials: D
authors.lastname: Zerini
authors.affiliation: Department of Medical Physics, European Institute of Oncology, Milan, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: De Marco
authors.affiliation: Department of Medical Physics, European Institute of Oncology, Milan, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Cattani
authors.affiliation: Department of Urology, European Institute of Oncology, Milan, Italy; Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy.
authors.forename: Ottavio
authors.initials: O
authors.lastname: De Cobelli
authors.affiliation: Scientific Direction, European Institute of Oncology, Milan, Italy; Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Orecchia
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019985:Benchmarking; D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000532:radiotherapy*; D061766:Proton Therapy / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D017430:Prostate-Specific Antigen
keywords: Carbon ions; Mix beam approach; Photons; Prostate cancer