title: A comparison of robotic arm versus gantry linear accelerator stereotactic body radiation therapy for prostate cancer.
abstract: Prostate cancer is the most prevalent cancer diagnosed in men in the United States besides skin cancer. Stereotactic body radiation therapy (SBRT; 6-15 Gy per fraction, up to 45 minutes per fraction, delivered in five fractions or less, over the course of approximately 2 weeks) is emerging as a popular treatment option for prostate cancer. The American Society for Radiation Oncology now recognizes SBRT for select low- and intermediate-risk prostate cancer patients. SBRT grew from the notion that high doses of radiation typical of brachytherapy could be delivered noninvasively using modern external-beam radiation therapy planning and delivery methods. SBRT is most commonly delivered using either a traditional gantry-mounted linear accelerator or a robotic arm-mounted linear accelerator. In this systematic review article, we compare and contrast the current clinical evidence supporting a gantry vs robotic arm SBRT for prostate cancer. The data for SBRT show encouraging and comparable results in terms of freedom from biochemical failure (>90% for low and intermediate risk at 5-7 years) and acute and late toxicity (<6% grade 3-4 late toxicities). Other outcomes (eg, overall and cancer-specific mortality) cannot be compared, given the indolent course of low-risk prostate cancer. At this time, neither SBRT device is recommended over the other for all patients; however, gantry-based SBRT machines have the abilities of treating larger volumes with conventional fractionation, shorter treatment time per fraction (~15 minutes for gantry vs ~45 minutes for robotic arm), and the ability to achieve better plans among obese patients (since they are able to use energies >6 MV). Finally, SBRT (particularly on a gantry) may also be more cost-effective than conventionally fractionated external-beam radiation therapy. Randomized controlled trials of SBRT using both technologies are underway.
authors: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA.
authors: Vladimir
authors: V
authors: Avkshtol
authors: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA.
authors: Yanqun
authors: Y
authors: Dong
authors: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA.
authors: Shelly B
authors: SB
authors: Hayes
authors: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA.
authors: Mark A
authors: MA
authors: Hallman
authors: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA.
authors: Robert A
authors: RA
authors: Price
authors: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA.
authors: Mark L
authors: ML
authors: Sobczak
authors: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA.
authors: Eric M
authors: EM
authors: Horwitz
authors: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA.
authors: Nicholas G
authors: NG
authors: Zaorsky
keywords: prostate cancer; quality of life; stereotactic body radiation therapy; technology