title: The rate of secondary malignancies after radical prostatectomy versus external beam radiation therapy for localized prostate cancer: a population-based study on 17,845 patients.
abstract: OBJECTIVE
  External-beam radiation therapy (EBRT) may predispose to secondary malignancies that include bladder cancer (BCa), rectal cancer (RCa), and lung cancer (LCa). We tested this hypothesis in a large French Canadian population-based cohort of prostate cancer patients.
  
  
  METHODS
  Overall, 8,455 radical prostatectomy (RP) and 9,390 EBRT patients treated between 1983 and 2003 were assessed with Kaplan-Meier and Cox regression analyses. Three endpoints were examined: (1) diagnosis of secondary BCa, (2) LCa, or (3) RCa. Covariates included age, Charlson comorbidity index, and year of treatment.
  
  
  RESULTS
  In multivariable analyses that relied on incident cases diagnosed 60 months or later after RP or EBRT, the rates of BCa (hazard ratio [HR], 1.4; p = 0.02), LCa (HR, 2.0; p = 0.004), and RCa (HR 2.1; p <0.001) were significantly higher in the EBRT group. When incident cases diagnosed 120 months or later after RP or EBRT were considered, only the rates of RCa (hazard ratio 2.2; p = 0.003) were significantly higher in the EBRT group. In both analyses, the absolute differences in incident rates ranged from 0.7 to 5.2% and the number needed to harm (where harm equaled secondary malignancies) ranged from 111 to 19, if EBRT was used instead of RP.
  
  
  CONCLUSIONS
  EBRT may predispose to clinically meaningfully higher rates of secondary BCa, LCa and RCa. These rates should be included in informed consent consideration.
authors.affiliation: Cancer Prognostics and Health Outcomes Unit, University of Montreal Health Center, Montreal, QC, Canada.
authors.forename: Naeem
authors.initials: N
authors.lastname: Bhojani
authors.forename: Umberto
authors.initials: U
authors.lastname: Capitanio
authors.forename: Nazareno
authors.initials: N
authors.lastname: Suardi
authors.forename: Claudio
authors.initials: C
authors.lastname: Jeldres
authors.forename: Hendrik
authors.initials: H
authors.lastname: Isbarn
authors.forename: Shahrokh F
authors.initials: SF
authors.lastname: Shariat
authors.forename: Markus
authors.initials: M
authors.lastname: Graefen
authors.forename: Philippe
authors.initials: P
authors.lastname: Arjane
authors.forename: Alain
authors.initials: A
authors.lastname: Duclos
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Lattouf
authors.forename: Fred
authors.initials: F
authors.lastname: Saad
authors.forename: Luc
authors.initials: L
authors.lastname: Valiquette
authors.forename: Francesco
authors.initials: F
authors.lastname: Montorsi
authors.forename: Paul
authors.initials: P
authors.lastname: Perrotte
authors.forename: Pierre I
authors.initials: PI
authors.lastname: Karakiewicz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005602:France / Q000208:ethnology; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000453:epidemiology / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009381:Neoplasms, Radiation-Induced / Q000453:epidemiology*; D016609:Neoplasms, Second Primary / Q000453:epidemiology* / Q000209:etiology; D011468:Prostatectomy / Q000009:adverse effects; D011471:Prostatic Neoplasms / Q000208:ethnology / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D011792:Quebec / Q000453:epidemiology / Q000208:ethnology; D011878:Radiotherapy / Q000009:adverse effects; D012004:Rectal Neoplasms / Q000453:epidemiology / Q000209:etiology; D012044:Regression Analysis; D001749:Urinary Bladder Neoplasms / Q000453:epidemiology / Q000209:etiology