With Real-Time Tracking – Good for Patients,
Good for Your Practice
Calypso’s technology provides the knowledge that prostate motion is accurately and precisely tracked to allow clinicians to confidently deliver the larger radiation doses per fraction called for by stereotactic body radiation therapy (SBRT) protocols. Calypso safeguards patients against unnecessary radiation by alerting the therapist when the prostate has moved outside of the radiation beam thereby exposing healthy tissue to unintended radiation. Patients further benefit from far fewer treatment sessions and the potential for decreased side effects.
Prostate SBRT delivers a higher dose of radiation per fraction while lowering the total number of treatments. Scientific literature suggests these larger doses per fraction of radiation may provide a radiobiological advantage over the more conventional approach which uses a smaller dose per fraction and a larger number of fractions. (i)
Shorter Course of Treatment
As compared to typical conventionally fractionated external beam radiotherapy delivered over 40-45 sessions, prostate SBRT is delivered in a 5-fraction protocol, so that the entire treatment course is delivered in less than two weeks. For the right patient, the much shorter delivery schedule combined with the potential for a more efficacious treatment makes SBRT a very appealing option.
Results of two clinical studies demonstrate that real-time tumor tracking with the Calypso® System during prostate SBRT enabled clinicians to reduce treatment margins and expose less healthy tissue to radiation. As compared to conventional radiotherapy, higher doses of radiation are used during each SBRT treatment session, therefore reducing treatment margins is an attractive option in limiting side effects and preserving the patient’s quality of life. (ii), (iii)
Maintains Quality of Life
SBRT heightens the need for accurate, precise real-time tracking of prostate motion. The delivery of these large doses of radiation over a shortened course of treatment creates concern about exposing the surrounding healthy tissue to the same high dose, thus increasing the potential for side effects. However, in a recent 54-patient clinical study using Calypso’s real-time tracking to guide prostate SBRT, there were no clinically significant declines in patient-reported quality of life in urinary, rectal or sexual domains. (iv)
Calypso’s real-time tracking monitors prostate location continuously throughout each treatment session so there is no need to interrupt radiation delivery to acquire frequent images that monitor prostate location. This decrease in treatment time provides an increase in overall linear accelerator capacity.
i. Mantz, C.A., Fernandez E., Zucker I., Harrison S. “A Phase II Trial of Real-time Target Tracking SBRT for Low-Risk Prostate Cancer Utilizing the Calypso 4D Localization System: Patient Reported Health-related Quality of Life and Toxicity Outcomes.” 21st Century Oncology, Fort Myers FL. Oral Presentation 121. ASTRO 2010.
iii. Jiang, L et al. “Dosimetric Evaluation of Margin Reduction and Intrafraction Motion for Prostate SBRT” University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, USA Poster 477. Congress of the European Society for Therapeutic Radiology and Oncology (ESTRO), 2011, London, U.K.
iv. Mantz, C. et al.
Before Calypso, our typical SBRT treatment would take 40 to 70 minutes because there was a frequent interruption of the treatment in order to shoot x-rays. This really slowed delivery of the treatment and increased the discomfort for our patients having to lie on the table for roughly an hour. With Calypso our typical SBRT treatment lasts 20 to 30 minutes.”
Constantine Mantz, M.D.
21st Century Oncology
Ft. Myers, FL.