AIM - We report our experience with Cyberknife to deliver hypofractionated stereotactic body radiotherapy (SBRT) boost combined with whole pelvis radiotherapy (WPRT) to patients with intermediate- to high-risk prostate cancer.
METHODS - From March 2008 to July 2014, 39 patients with newly diagnosed, intermediate- and high-risk (National Comprehensive Cancer Network definition) localized prostate cancer were treated with WPRT and SBRT boost. The whole pelvis dose was 45 Gy (25 fractions of 1. 8 Gy) and the SBRT boost dose was 21 Gy (3 fractions of 7 Gy). No one received androgen deprivation therapy before biochemical relapse. The acute and late toxicities were recorded using the Radiation Therapy Oncology Group scale. Prostate-specific antigen (PSA) response was monitored.
RESULTS - Thirty-nine patients with a median 53. 6 months (range 14-74 months) follow-up were analyzed. The median pretreatment PSA was 15. 97 ng/mL. The estimated 5-year biochemical failure (BCF)-free survival was 94. 7%. Two BCFs were observed in only high-risk group. The median PSA nadir was 0. 30 ng/mL at median 36 months and PSA bounce occurred in 15. 4% (n = 6) of patients at median 12 months. No grade 3 acute toxicity was noted. A total of 23% of the patients had grade 2 acute genitourinary (GU) toxicities and 21% had grade 2 acute gastrointestinal (GI) toxicities. At 2 months, most complications had returned to baseline. GU and GI toxicities were observed.
CONCLUSIONS - WPRT followed by SBRT boost using Cyberknife in intermediate- and high-risk prostate cancer is feasible with minimal toxicity and encouraging BCF-free survival.
Asia-Pacific journal of clinical oncology. 2016 Feb 05 [Epub ahead of print]
Hun Jung Kim, Jeong Hoon Phak, Woo Chul Kim
Department of Radiation Oncology, Inha University Hospital, Inha University of Medicine, Inchon, Korea. , Department of Radiation Oncology, Inha University Hospital, Inha University of Medicine, Inchon, Korea. , Department of Radiation Oncology, Inha University Hospital, Inha University of Medicine, Inchon, Korea.