Stereotactic Body Radiation Therapy (SBRT)

Stereotactic Body Radiation Therapy (SBRT), also called stereotactic ablative radiotherapy (SABR), is a pinpoint-accurate radiation delivery system offered by Martin-O’Neil Cancer Center. The technology is designed to precisely target cancer tissue while minimizing exposure to healthy surrounding tissue.

SBRT can be used to non-invasively treat small, well-defined tumors in the lung, liver, spine, or other areas that may not respond well to surgery, chemotherapy, conventional radiation, or other treatments. SBRT is especially useful when the patient is not a good candidate for conventional surgery or other treatments; the tumor’s location makes it inoperable; other therapies have failed to halt the cancer’s growth; or when the patient has undergone previous conventional radiation therapy. It can also be used on very small tumors or lesions, allowing oncologists to begin treatment at the earliest possible stage of cancer development, when it’s most effective, and treat isolated recurrences or metasteses quickly.

This technology represents a major clinical advance, especially for patients with cancers that might previously have been considered difficult to treat. Early studies have shown survival rates nearly double those of conventional radiation therapy, and the power and precision of the delivery system translates into both improved patient outcomes and improved quality of life during and after treatment. Effectiveness rivals surgery, with fewer risks.

Using a variety of conventional and leading-edge imaging technologies, the physician creates a custom map of each individual patient’s anatomy and locates the tumor precisely in four dimensions. A specially designed coordinate-system is used for the exact localization of the tumors in the body. The technologist then creates an individualized “Body-Fix” mold of the patient’s body to ensure exact positioning for each treatment. Once the patient is precisely positioned, the Trilogy™ Stereotactic System from Varian Medical Systems uses multiple beams guided by real-time radio imaging to precisely target cancer tissue with high-energy radiation. Because the system converges multiple, lower-dose beams from several angles, it actually targets a 3-dimensional model of the cancer. This accuracy concentrates the power of the beams inside the tumor or lesion, not on surrounding tissue. More radiation can be delivered per treatment without damaging healthy tissue, which means more cancer destroyed, with fewer treatments needed. Instead of a course of treatment delivered in daily “fractions” over a period of weeks, patients may receive a single treatment, or up to five fractions several days apart.

The result is that physicians are able to deliver a higher combined dose of radiation in far fewer treatments, while effectively protecting nearby healthy tissue. This precision means that cancer cells are destroyed more effectively, creating better outcomes, while significantly reducing side effects. SBRT has shown dramatically better outcomes than conventional radiation therapy.

The list of cancers that has been treated successfully with SBRT continues to grow, and includes primary and metastatic tumors in the lungs, pancreas, bile duct, central nervous system, liver, kidney, prostate and pelvic region, as well as sarcomas and metastatic tumors throughout the body. The treatment is not suitable for all cancers or for all patients: your radiation oncologist will evaluate whether SBRT is an appropriate treatment for your case.