“More and more people understand that the use of radiation can deliver treatment to any part of the body, and we now have more flexibility in terms of what doses to give for radiation and to treat anatomic sites that would be inaccessible through surgery,” Dr Iyengar said.
“If a patient has primary lung cancer and a few sites of metastatic disease, I would want to give chemotherapy first to keep any disease that may develop under control, and give chemotherapy a chance to shrink the disease in the primary and metastatic sites,” Dr Iyengar said. “Then I would use radiation after initial chemotherapy to access any of the other sites of metastases that are not accessible with surgery.”
Dr Iyengar discussed a small trial conducted at UT Southwestern Medical Center that included 24 patients with NSCLC who progressed on first-line chemotherapy. Instead of receiving a second-line chemotherapy, the patients underwent radiation to all limited metastatic sites combined with the targeted therapy erlotinib (used before there was knowledge of which patients would benefit from the drug). The patients in the study had a median survival of about 20 to 21 months.
“If you look at the standard patients with NSCLC who had progressed through chemotherapy, their survival is less than 12 months,” Dr Iyengar said. “There have been other studies done by other groups, including institutional evaluations or meta-analyses of smaller studies, and the overall survival in this patient population always tends to be in the 21- to 22-months range.
“With these treatments, I think we have a chance to take what would traditionally be a year-long survival and make it go out to 1.5 to 2 years,” he said.
The final treatment approach discussed was RFA. For patients with NSCLC, most of the literature on RFA has been in patients with high-risk disease, though Dr Iyengar noted that overall data are still scant on using RFA in the limited metastatic setting.
“In the limited metastatic setting, the only reason to use RFA is if, for some reason, the patient has already received radiation, the disease recurred, and it is not safe to give radiation to the same area,” Dr Iyengar said.
When trying to identify which option may be best for a patient, Dr Iyengar stressed the use of a multidisciplinary team.
- Iyengar P, Lau S, Donington JS, Suh RD. Local therapy for limited metastatic non-small lung cancer: What are the options and is there a benefit? Am Soc Clin Oncol Educ Book. 2016;35:e460-467.
- Iyengar P, Kavanagh BD, Wardak Z, et al. Phase II trial of stereotactic body radiation therapy combined with erlotinib for patients with limited but progressive metastatic non-small cell lung cancer. J Clin Oncol.2014;32:3824-3830.