title: Fractionated high-dose-rate brachytherapy as monotherapy in prostate cancer: Does implant displacement and its correction influence acute and late toxicity?
abstract: In fractionated high-dose-rate brachytherapy (HDR-BT) for prostate cancer (PCa) with one implant for several fractions, dose delivery relies on reproducibility of catheter positions. However, caudal displacement of implanted catheters does occur between fractions and needs to be corrected. Our protocol prescribes correction of displacements > 3 mm. We investigated whether displacement and its corrections influence acute and late toxicity incidences.
  
  
  
  We analyzed 162 PCa patients treated with HDR-BT monotherapy between 2007 and 2013. The implant remained in situ between the 4 fractions. Catheter displacement was assessed before each fraction using lateral X-ray images and corrected if needed. Genitourinary (GU) and gastrointestinal (GI) acute and late toxicities were assessed using clinical record forms and patient self-assessment questionnaires.
  
  
  
  Implant displacement corrections (DC) were needed in 71 patients (43.8%) whereas no DCs were needed in 91 patients (56.2%). No statistically significant differences were seen in acute and late grade ≥ 2 GU and GI toxicity incidences between DC and no DC groups. The maximum displacement nor the number of corrections had any influence on toxicity.
  
  
  
  The occurrence and subsequent correction of implant displacements exceeding 3 mm during fractionated HDR-BT monotherapy for PCa did not lead to increased incidences of acute or late GU and GI toxicity. This indicates that our clinical protocol to correct displacements > 3 mm results in safe treatment regarding organ at risk toxicity.
authors.affiliation: Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands. Electronic address: s.aluwini@erasmusmc.nl.
authors.forename: Shafak
authors.initials: S
authors.lastname: Aluwini
authors.affiliation: Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: Wendy M H
authors.initials: WM
authors.lastname: Busser
authors.affiliation: Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: Lizette E A
authors.initials: LE
authors.lastname: Baartman
authors.affiliation: Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: Anand
authors.initials: A
authors.lastname: Bhawanie
authors.affiliation: Clinical Trials Center, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: Wendimagegn G
authors.initials: WG
authors.lastname: Alemayehu
authors.affiliation: Department of Urology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: Joost L
authors.initials: JL
authors.lastname: Boormans
authors.affiliation: Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: Inger-Karine K
authors.initials: IK
authors.lastname: Kolkman-Deurloo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects* / Q000379:methods; D057785:Catheters; D019583:Dose Fractionation, Radiation; D004868:Equipment Failure; D005548:Foreign-Body Migration; D005767:Gastrointestinal Diseases / Q000209:etiology*; D006801:Humans; D008297:Male; D052801:Male Urogenital Diseases / Q000209:etiology*; D008875:Middle Aged; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000209:etiology*; D015203:Reproducibility of Results
keywords: Catheter displacement and correction; HDR-Brachytherapy; Prostate cancer; Radiotherapy; Toxicity