title: Risk of second cancer following radiotherapy for prostate cancer: a population-based analysis.
abstract: BACKGROUND
  To investigate the risk of second cancer and radiation induced second cancer following prostate cancer radiotherapy.
  
  
  METHODS
  We compared men with radiotherapy only with those treated with radical prostatectomy only and those with radiotherapy after radical prostatectomy. Cumulative incidences of second cancers were calculated. Cox analyses were performed to identify determinants influencing second cancer incidence.
  
  
  RESULTS
  Nineteen thousand five hundred thirty eight patients were analyzed. Age and median follow-up differed significantly with radiotherapy only patients having the highest median age (70.3 years) and radical prostatectomy only patients the longest median follow-up (10.2 years). Ten-year cumulative incidence of second cancer was 15.9%, 13.2% and 10.5% for patients with radiotherapy only, radiotherapy after radical prostatectomy and radical prostatectomy only (p <0.0001). Increasing age and belonging to the radiotherapy only group were associated with a higher risk of second cancer-no significant increase was seen in radiotherapy after radical prostatectomy patients. A significantly higher rate of smoking related malignancies, like lung, bladder and non-melanoma skin cancer, was seen in radiotherapy only patients.
  
  
  CONCLUSIONS
  No clear increase in radiation induced second cancer was found in patients after radiotherapy for prostate cancer. Whereas the rate of second cancer was increased in radiotherapy only patients, no such increase was seen in patients with radiotherapy after radical prostatectomy. The increase of second cancer following radiotherapy only is highly likely to reflect advanced age and lifestyle habits and comorbidities.
authors.affiliation: Department of Radiation Oncology, Klinikum der Universität, Ludwig-Maximilians-University, LMU Munich, Marchioninistr 15, 81377, Munich, Germany. Nina-Sophie.Hegemann@med.uni-muenchen.de.
authors.forename: Nina-Sophie
authors.identifier: http://orcid.org/0000-0002-2091-3603
authors.initials: NS
authors.lastname: Hegemann
authors.affiliation: Munich Cancer Registry (MCR) of the Munich Cancer Centre (MCC) at the Department of Medical Informatics, Biometry and Epidemiology (IBE), University of Munich, Marchioninistr 15, 81377, Munich, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Schlesinger-Raab
authors.affiliation: Department of Radiation Oncology, Klinikum der Universität, Ludwig-Maximilians-University, LMU Munich, Marchioninistr 15, 81377, Munich, Germany.
authors.forename: Ute
authors.initials: U
authors.lastname: Ganswindt
authors.affiliation: Department of Radiotherapy, Klinikum Schwabing, Kölner Pl 1, 80804, Munich, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Hörl
authors.affiliation: Department of Radiation Oncology, Klinikum Rechts der Isar, Technical University (TU), Ismaningerstr 22, 81675, Munich, Germany.|Institute of Innovative Radiotherapy (iRT), Helmholtz Centre, Munich, Germany.
authors.forename: Stephanie E
authors.initials: SE
authors.lastname: Combs
authors.affiliation: Munich Cancer Registry (MCR) of the Munich Cancer Centre (MCC) at the Department of Medical Informatics, Biometry and Epidemiology (IBE), University of Munich, Marchioninistr 15, 81377, Munich, Germany.
authors.forename: Dieter
authors.initials: D
authors.lastname: Hölzel
authors.affiliation: Department of Urology, Klinikum Rechts der Isar, Technical University (TU), Ismaningerstr 22, 81675, Munich, Germany.
authors.forename: Jürgen E
authors.initials: JE
authors.lastname: Gschwend
authors.affiliation: Department of Urology, Klinikum der Universität, Ludwig-Maximilians-University, LMU Munich, Marchioninistr 15, 81377, Munich, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Stief
authors.affiliation: Department of Radiation Oncology, Klinikum der Universität, Ludwig-Maximilians-University, LMU Munich, Marchioninistr 15, 81377, Munich, Germany.
authors.forename: Claus
authors.initials: C
authors.lastname: Belka
authors.affiliation: Munich Cancer Registry (MCR) of the Munich Cancer Centre (MCC) at the Department of Medical Informatics, Biometry and Epidemiology (IBE), University of Munich, Marchioninistr 15, 81377, Munich, Germany.
authors.forename: Jutta
authors.initials: J
authors.lastname: Engel
mesh_terms: D000368:Aged; D001918:Brachytherapy / Q000009:adverse effects*; D005500:Follow-Up Studies; D005858:Germany / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009381:Neoplasms, Radiation-Induced / Q000453:epidemiology / Q000209:etiology*; D016609:Neoplasms, Second Primary / Q000453:epidemiology / Q000209:etiology*; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D012307:Risk Factors; D015996:Survival Rate
keywords: Prostate cancer; Radiotherapy; Second cancer