A new tool in the fight against lung cancer: SBRT
July 1, 2015
One of the greatest gifts our patients here at UT Southwestern can give others is choosing to be part of a clinical trial. The patients gain access to new, potentially life-saving therapies. In return, the findings help us determine what treatments work.
The treatment of early-stage lung cancer is a great example of how clinical trials can help. Through testing and research, physicians here and throughout the country have developed stereotactic body radiation therapy (SBRT) to treat lung cancer. SBRT has been used in the past to treat other types of tumors, but using it to fight lung cancer is especially exciting.
SBRT, also sometimes referred to as stereotactic ablative therapy (SABR), points an intense dose of radiation directly at a lung cancer tumor. The radiation damages the very DNA in the cells of the tumor, causing them to stop dividing. The tumor then shrinks and ultimately dies. This can lead to the curing of the cancer.
Benefits of SBRT
Because SBRT treatments are delivered on an outpatient basis, our patients experience minimal disruption to their daily life. Patients are usually treated three to five times, and each visit lasts about an hour. SBRT is a noninvasive procedure, meaning we don’t make any incisions, and no hospitalization is required. You can receive treatment and go straight home or to work.
The reason that SBRT requires fewer treatments is because of the advanced nature of the technology. Radiation therapy used to be less precise. Often, to get radiation to a tumor, healthy tissue was radiated along with the tumor, which caused side-effects such as fatigue, nausea, and skin sensitivity. SBRT, however, is so precise that very little beyond the cancerous tissue receives radiation, and with this precision we can administer a much stronger dose of radiation at one time.
In the past, in order to limit damage to healthy tissue with less-precise treatments, radiation doses were necessarily much weaker and had to be spread out over a much longer period. Typical treatments took more than six weeks to accomplish what SBRT now can do in a few visits.
SBRT outcomes and lung cancer survival rates
Depending on the circumstances of a particular tumor, or tumors, additional treatment might be necessary.
Studies have shown that 95 percent of the primary lung tumors treated with SBRT are eliminated, meaning that they cease to be harmful. This is a vast improvement over the 50 percent rate doctors saw with previous types of radiation therapy. The success rate really is staggering, but keep in mind that all tumors are different, and, as such, behave differently with radiation. While many of these are ultimately cured, some patient’s tumors have spread in a way that can’t be identified prior to treatment. This hidden tumor may relapse causing some patients to need additional treatment or take medications.
Surgery has long been the standard treatment for early-stage lung cancer, but we often see patients who cannot tolerate surgery. In the past, these patients often would not receive any treatment for their lung cancer, including radiation. With SBRT, we have seen many such patients not only be treated, but cured. This has been very gratifying.
We hope to take the next step very soon. UT Southwestern’s Simmons Cancer Center will be leading a national clinical trial later this year to compare SBRT to a surgery used for high-risk patients. Known as the Stablemate’s Trial, it will collect data at more than 40 sites in the United States and Canada.
We have the brave trailblazers, our clinical trial patients, to thank for the success of SBRT. Without them, our understanding of radiation for the treatment of all types of cancer would be creeping along at a much slower rate than it is now.
For information about how you can join a clinical trial, talk to your doctor – or search the clinical trials currently underway at UT Southwestern.