Tim Lautenschlaeger, MD, and colleagues recently wrote “Histology, Tumor Volume, and Radiation Dose Predict Outcomes in Non-small Cell Lung Cancer Patients after Stereotactic Ablative Radiotherapy.” The research was published in the Journal of Thoracic Oncology. (Alberto Cerra, MD, a fifth-year radiation oncology resident, delivered an oral presentation about the study's results at the American Society for Radiation Oncology [ASTRO] meeting on Oct. 23.)
Dr. Lautenschlaeger answered questions about this study.
Q: In your words, what is the single main purpose of this study?
Dr. Tim Lautenschlaeger: To understand what the best radiation dose is for each individual patient with early stage (stage I) non-small cell lung cancer.
Q: What are the key findings/results?
Dr.Tim Lautenschlaeger: There are two common subtypes of non-small cell lung cancers: adenocarcinomas and squamous cell carcinomas. We found that squamous cell carcinomas can be better controlled with a higher radiation dose. For adenocarcinomas, that seems to not be the case and all commonly used radiation doses provided good local cancer control.
Q: What is the significance of the finding(s)? Is it new? Does it confirm anything?
Dr. Tim Lautenschlaeger: It is the third and so far most definitive paper suggesting that some of the lower common radiation doses should not be used for squamous cell carcinoma patients if there are no specific reasons why this cannot be done. This is, however, a retrospective study and not a randomized clinical trial, so the results need to be interpreted with caution.
Q: What are the strengths of your study?
Dr. Tim Lautenschlaeger: Our study is one of the largest on lung SBRT with one of the longest follow-ups (median follow up more than six years) published to date.
Q: What are the implications of your findings? Are there clinical applications that can be applied in the next few years?
Dr.Tim Lautenschlaeger: Currently there are a wide variety of acceptable radiation dose prescriptions for early stage NSCLC patients. No guidance exists as to which of the acceptable radiation dose prescriptions are preferable. Based on our study, we suggest that patients with early stage squamous cell carcinoma of the lung should receive radiation doses that are at the higher end of the spectrum of acceptable doses as long as there are no specific reasons why this should not be done. Also, based on these study results, we wrote and opened a clinical trial evaluating if local cancer control can be improved by giving higher radiation doses for squamous cell carcinomas.
