Among patients with Stage III non-small cell lung cancer, treatment with a higher dose of radiation therapy does not result in better overall survival than a standard dose of radiation therapy. These results were presented at the 53rd Annual Meeting of the American Society for Radiation Oncology (ASTRO).
Lung cancer remains the leading cause of cancer death in the United States. Non–small cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancers.
Treatment of NSCLC may involve surgery, chemotherapy, targeted therapy, radiation therapy, or some combination of these approaches. For patients who are treated with radiation therapy, there has been interest in whether higher doses of radiation therapy could improve treatment outcomes.
Two different doses of radiation therapy (given in combination with chemotherapy) were evaluated in a Phase III clinical trial of patients with Stage III NSCLC. The study was also designed to assess the effectiveness of the targeted therapy Erbitux® (cetuximab), so patients were assigned to one of four treatment groups:
- High-dose radiation therapy plus chemotherapy
- High-dose radiation therapy plus chemotherapy plus Erbitux
- Standard-dose radiation therapy plus chemotherapy
- Standard-dose radiation therapy plus chemotherapy plus Erbitux
Patients in the high-dose radiation groups received a total of 74 Gy of radiation. Patients in the standard-dose radiation groups received a total of 60 Gy of radiation.
At the first planned check of the data, it was apparent that 74 Gy of radiation therapy was no more effective than 60 Gy. As a result, this part of the study was stopped early.
Patients continue to be enrolled into the standard-dose radiation groups in order to fully assess the safety and efficacy of Erbitux.
In short, increasing the radiation dose from 60 Gy to 74 Gy did not improve outcomes among patients who also received chemotherapy for Stage III non-small cell lung cancer. In addition to being as effective as the higher dose, the 60 Gy dose offers the advantage of requiring fewer days of treatment.
Reference: Bradley JD, Paulus R, Komaki R et al. A randomized phase III comparison of standard-dose (60 Gy) versus high-dose (74 Gy) conformal chemoradiotherapy +/- cetuximab for stage IIIA/IIIB non-small cell lung cancer: preliminary findings on radiation dose in RTOG 0617. Presented at the 53rd Annual Meeting of the American Society for Radiation Oncology (ASTRO). Miami Beach, FL, October 2-6, 2011. Abstract LB2.