ASCO 2013: Standard-dose Radiation Is Superior to High-dose Radiation for Patients with Locally Advanced Stage III NSCLC Undergoing Chemotherapy
A phase III trial in patients with stage III non–small cell lung cancer (NSCLC) concluded that standard-dose radiotherapy (60 Gy) is safer and more effective than high-dose radiotherapy (74 Gy), extending survival by 9 months and causing fewer treatment-related deaths. While 60 Gy is already standard, many doctors use higher doses expecting better outcomes. These findings should put an end to higher-dose treatment, given better outcomes in the standard-dose arm. The results will be presented at the 2013 ASCO Annual Meeting in Chicago in June (Abstract 7501).
Radiation therapy is used to control the growth of the primary tumor and cancer spread to the nearby lymph nodes. Although high-dose therapy in this patient population appeared promising in earlier phase I and phase II clinical trials, this study clearly shows that it is associated with dramatically shorter survival.
“We expected at the outset that high-dose radiation therapy would lead to better outcomes. We were surprised, though also pleased, to discover that less-intense treatment led to better control of cancer progression and spread, and even improved overall survival,” said lead author Jeffrey D. Bradley, MD, Professor of Radiation Oncology at the Washington University School of Medicine in St. Louis. “The biological reasons for failure of the high dose with respect to overall survival and local-regional control are not readily apparent.”
Trial Details
In the study, 464 patients were randomly assigned to treatment with standard-dose or high-dose radiation therapy along with standard chemotherapy (paclitaxel and carboplatin). In each treatment arm, the patients were also randomly assigned to receive cetuximab (Erbitux) or no additional therapy. Data on the effects of cetuximab on survival will be reported at a later date. The high-dose arm was closed after an interim analysis showed it was not superior to the standard-dose arm.
The median survival for patients who received standard-dose radiation therapy was much longer compared to that in patients who received high-dose radiation therapy (28.7 vs 19.5 months) and the estimated 18-month overall survival rates were also higher for the standard-dose arm (66.9% vs 53.9%). Cancer recurrence rates at 18 months were higher in the high-dose group of patients compared with the standard-dose group (local recurrence rates were 34.3% vs 25.1%, and distant recurrence rates were 44% vs 35.3%). While the primary cause of death for most patients was lung cancer, there were a notably higher number of treatment-related deaths in the high-dose arm (10), compared to the standard-dose arm (2).
Critical Study
“This is a critical study in the field of radiation oncology,” commented ASCO President Sandra M. Swain, MD, FACP. “After a decade of research, we can finally close the chapter on the high-dose vs standard-dose therapy debate in lung cancer therapy, using evidence-based data to improve care for our patients.”
This research was supported by the National Cancer Institute and Eli Lilly and Company.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
