title: Stereotactic body re-irradiation therapy for locally recurrent prostate cancer after external-beam radiation therapy: Initial report.
abstract: OBJECTIVE
  Management of prostate cancer relapses after external-beam radiation therapy is still undefined. Re-irradiation schedules have been explored in different tumour sites. In this report, we present our preliminary experience of re-irradiation using stereotactic body radiotherapy for localized prostate cancer failure.
  
  
  METHODS
  Between March 2011 and October 2014, robotic stereotactic body radiation therapy was administered to patients previously treated with external-beam radiation therapy to a median dose of 71.1Gy (range, 45-76.5Gy) and with biochemical failure corresponding to a local in-field recurrence of prostate cancer. Ten patients had recurrences after postoperative external-beam radiotherapy. Patients underwent a pelvic MRI to confirm the recurrence and a total body staging using a ((18)F)-fluorocholine PET/CT. The prescription dose consisted of five fractions of 7.25Gy to a total dose of 36.25Gy. Efficacy was evaluated based on biochemical response and toxicity was evaluated according to CTCAE v.4.0 questionnaires and International Prostate Symptom Score.
  
  
  RESULTS
  Twenty-one patients were treated and followed for a median time of 11.7 months (mean: 13.4 months; range: 2.5-46.5 months). Median time between the first external-beam radiation therapy of prostate cancer and the first day of CyberKnife(®) treatment was 111 months (range: 38-398 months). One-year biochemical recurrence-free survival rate was 83.3%, and only one in-field progression was reported. Two patients had a biochemical failure corresponding to metastatic progression without evidence of local recurrence. Treatment was well tolerated, with only one grade 2 acute genitourinary toxicity, no grade≥2 acute gastrointestinal or late toxicities were reported.
  
  
  CONCLUSIONS
  Stereotactic body re-irradiation therapy using CyberKnife(®) after failed external-beam radiation therapy showed favourable results in terms of in-field local and biochemical control. Toxicity was low and acceptable. Further prospective studies are needed to confirm these results to select patient and to evaluate the introduction of androgen-deprivation therapy.
authors.affiliation: Oncology-Radiotherapy Department, Henry-S.-Kaplan Cancer Center, CHRU de Tours, 2, boulevard Tonnellé, 37000 Tours, France; Université François-Rabelais, 37000 Tours, France. Electronic address: guillaume.janoray@yahoo.fr.
authors.forename: G
authors.initials: G
authors.lastname: Janoray
authors.affiliation: Oncology-Radiotherapy Department, Henry-S.-Kaplan Cancer Center, CHRU de Tours, 2, boulevard Tonnellé, 37000 Tours, France; Université François-Rabelais, 37000 Tours, France.
authors.forename: A
authors.initials: A
authors.lastname: Reynaud-Bougnoux
authors.affiliation: Oncology-Radiotherapy Department, Henry-S.-Kaplan Cancer Center, CHRU de Tours, 2, boulevard Tonnellé, 37000 Tours, France; Université François-Rabelais, 37000 Tours, France.
authors.forename: A
authors.initials: A
authors.lastname: Ruffier-Loubière
authors.affiliation: Oncology-Radiotherapy Department, Henry-S.-Kaplan Cancer Center, CHRU de Tours, 2, boulevard Tonnellé, 37000 Tours, France; Université François-Rabelais, 37000 Tours, France.
authors.forename: G
authors.initials: G
authors.lastname: Bernadou
authors.affiliation: Oncology-Radiotherapy Department, Henry-S.-Kaplan Cancer Center, CHRU de Tours, 2, boulevard Tonnellé, 37000 Tours, France; Université François-Rabelais, 37000 Tours, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Pointreau
authors.affiliation: Oncology-Radiotherapy Department, Henry-S.-Kaplan Cancer Center, CHRU de Tours, 2, boulevard Tonnellé, 37000 Tours, France; Université François-Rabelais, 37000 Tours, France.
authors.forename: G
authors.initials: G
authors.lastname: Calais
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019583:Dose Fractionation, Radiation; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D016634:Radiosurgery; D061089:Radiotherapy, Image-Guided; D000069475:Re-Irradiation
chemical_list: D017430:Prostate-Specific Antigen
keywords: Cancer de prostate; Contrôle local; CyberKnife(®); Local control; Prostate cancer; Radiothérapie stéréotaxique; Re-irradiation; Relapse; Ré-irradiation; Récidive; SBRT