title: [Chronic gastrointestinal toxicity after external-beam radiation therapy for prostate cancer].
abstract: BACKGROUND
  Chronic gastrointestinal (GI) toxicity is an important dose-limiting factor of prostate cancer treatment. Its incidence varies with the dose of radiotherapy and the external beam treatment technique; however, there are also other factors that should be considered. Despite all the efforts to diminish the incidence, chronic toxicity still remains an adverse event which can affect the quality of life in patients after prostate cancer radiotherapy.
  
  
  METHODS
  The aim of this review is to provide a detailed description of chronic GI toxicity after external beam radiation therapy for prostate cancer, its causes, development, symptoms and incidence in different treatment techniques, and to compare the development of GI toxicity from the beginning of curative prostate cancer radiotherapy to now.
  
  
  CONCLUSIONS
  Thanks to up-to-date radiotherapy techniques, the incidence of chronic GI toxicity is relatively low despite high doses of about 80 Gy used in prostate cancer treatment. Further reduction of radiation complications could be achieved by using image-guided radiotherapy (IGRT), which enables more precise delivery of the radiation dose to the prostate, reduction of the margin around the clinical target volume (CTV) and the sparing of organs at risk.
authors.affiliation: Klinika onkologie a radioterapie, FN Hradec Králové. sefrova@fnhk.cz
authors.forename: J
authors.initials: J
authors.lastname: Sefrová
authors.forename: P
authors.initials: P
authors.lastname: Paluska
authors.forename: K
authors.initials: K
authors.lastname: Odrázka
authors.forename: V
authors.initials: V
authors.lastname: Jirkovský
mesh_terms: D002908:Chronic Disease; D041981:Gastrointestinal Tract / Q000473:pathology / Q000528:radiation effects*; D006801:Humans; D008297:Male; D011349:Proctitis / Q000209:etiology / Q000473:pathology; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000473:pathology*; D011879:Radiotherapy Dosage; D012307:Risk Factors