title: High-Dose Robotic Stereotactic Body Radiotherapy in the Treatment of Patients With Prostate Cancer: Preliminary Results in 26 Patients.
abstract: BACKGROUND
  Stereotactic body radiotherapy (SBRT) can emulate high dose rate brachytherapy (HDR-BRT) dose fractionation. We report our preliminary results using SBRT in monotherapy or pre-external-beam radiotherapy (EBRT) boost in patients with localized prostate cancer (LpC). The primary end point was the evaluation of both acute and late toxicities; secondary end point was the observation of prostate-specific antigen (PSA) nadir.
  
  
  METHODS
  Patients with LpC having prostate volume ≤90 cm(3) were enrolled in the present study. Patients were treated with SBRT alone or in combined modality (SBRT + EBRT). SBRT was performed using a CyberKnife System (Accuray Incorporated, Sunnyvale, California) and fiducial tracking system.
  
  
  RESULTS
  From February 2008 to July 2013, 21 patients for monotherapy (38 Gy/4 fractions) and 5 for combined modality (9.5 Gy/2 fractions plus 46 Gy/23 fractions EBRT) were enrolled. Androgen deprivation therapy (ADT) was administered in 16 of the 26 patients. The median pretreatment PSA was 9.4 (range, 4.5-14.3) ng/mL. All patients completed the planned therapy. Acute Grade 1 toxicity was observed in 18 patients, genitourinary (GU) in 12 / 26 patients, and gastrointestinal (GI) in 6 / 26 patients. Acute Grade 2 GU toxicity was reported in 1 / 26 patients, and Grade 2 GI toxicity was observed in 2 / 26 patients. The median PSA nadir was 0.15 (range, 0.02 = 1.4) ng/mL. Late toxicities were observed in 5 / 26 patients: Grade 1 GU (3 of 26), Grade 2 GU (1 of 26), and Grade 1 GI (1 of 26). Median follow-up was 21.5 (range, 8-65) months.
  
  
  CONCLUSIONS
  Our preliminary results of SBRT "simulating" HDR for LpC confirm a minimal toxicity and an optimal PSA response. The PSA nadirs appear comparable with HDR-BRT.
authors.affiliation: Department of Biomedical Sciences and Morphological and Functional Images, University of Messina, Messina, Italy apontoriero@unime.it.
authors.forename: A
authors.initials: A
authors.lastname: Pontoriero
authors.affiliation: A.O.U. "G. Martino", Operative Unit of Radiation Oncology, Messina, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Iatì
authors.affiliation: Department of Neuroscience Messina, University of Messina, Messina, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Mondello
authors.affiliation: A.O.U. "G. Martino", Operative Unit of Radiation Oncology, Messina, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Midili
authors.affiliation: A.O.U. "G. Martino", Operative Unit of Radiation Oncology, Messina, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Siragusa
authors.affiliation: A.O.U. "G. Martino", Operative Unit of Radiation Oncology, Messina, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Brogna
authors.affiliation: A.O.U. "G. Martino", Operative Unit of Radiation Oncology, Messina, Italy.
authors.forename: I
authors.initials: I
authors.lastname: Ielo
authors.affiliation: A.O.U. "G. Martino", Operative Unit of Radiation Oncology, Messina, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Anastasi
authors.affiliation: Department of General Surgery, Oncology and Pathology, University of Messina, Messina, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Magno
authors.affiliation: Department of Biomedical Sciences and Morphological and Functional Images, University of Messina, Messina, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Pergolizzi
authors.affiliation: Department of Biomedical Sciences and Morphological and Functional Images, University of Messina, Messina, Italy.
authors.forename: C
authors.initials: C
authors.lastname: De Renzis
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D019583:Dose Fractionation, Radiation; D005500:Follow-Up Studies; D006801:Humans; D007610:Kallikreins / Q000097:blood; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000601:surgery*; D016634:Radiosurgery; D011880:Radiotherapy Planning, Computer-Assisted; D012371:Robotics; D025321:Surgery, Computer-Assisted; D016896:Treatment Outcome
chemical_list: C549870:KLK3 protein, human; D007610:Kallikreins; D017430:Prostate-Specific Antigen
keywords: CyberKnife; prostate cancer; stereotactic body radiation therapy