Adding stereotactic body radiation therapy to chemotherapy improved stage 4 lung cancer patients’ survival rates in a recent study from UT Southwestern Medical Center. The researchers combined this radiation therapy, known as SBRT, with erlotinib and saw a greater than twofold increase in overall survival time.
“Our approach dramatically changed the pattern of relapse,” said Dr. Robert Timmerman, senior author and Director of the Annette Simmons Stereotactic Treatment Center, in a news release from UT Southwestern. “We saw a shift in failure from existing, local sites to new, distant sites. This shift resulted in a surprisingly long remission from the reappearance of cancer in treated patients.”
Remission time increased patient survival time from the historic six to nine months to 20 months. Similarly, the combination treatment increased progression free survival from the historic two to four months to 14.7 months. This may in the future lead to better five year relative survival rates, which are generally low at only 16.8%.
During the researchers’ phase 2 clinical trial, 24 patients enrolled with stage 4 non-small cell lung cancer (NSCLC, the most common type of lung cancer) that continued to spread despite initial therapy. Although SBRT is not typically administered to NSCLC patients with poor survival rates, “Technologies have developed in the last few years that have yielded game-changing, paradigm-shifting approaches, allowing us to reconsider how radiation is delivered in combination with surgery, chemotherapy, and other systemic therapies,” said Dr. Timmerman.
Stereotactic body radiation therapy is a treatment procedure designed to target tumors outside the central nervous system, in order to treat it with limited but precise, high doses of radiation or a few fractionated radiation treatments. Small but strong doses of radiation are delivered from different angles directly to the tumors, with the intent to treat the patient while decreasing the damage to the surrounding healthy tissue.
Previous studies with SBRT identified better cure rates for metastatic and other cancers. Dr. Timmerman was one of the first clinicians to ever use SBRT to treat body cancers–SBRT was originally developed for brain tumors. “I am motivated by the need I see every day in the clinic to provide better treatment for our patients.” Joining Dr. Timmerman in this goal was Dr. Puneeth Iyengar, first author of their paper, “Phase II Trial of Stereotactic Body Radiation Therapy Combined With Erlotinib for Patients With Limited but Progressive Metastatic Non–Small-Cell Lung Cancer,” published in Journal of Clinical Oncology.