Patients with lung cancer live longer when surgery is followed by radiation therapy, but only if the disease is at an advanced stage, according to a study by Yale School of Medicine researchers published in the Journal of Clinical Oncology.
The analysis of 7,465 patients found that in patients whose lung cancer had spread to the regional lymph nodes between the lungs (mediastinal), overall survival at five years was 27 percent in patients receiving surgery plus radiation therapy compared to 20 percent in patients who were treated with surgery alone.This analysis of outcomes for a very large group of patients shows that post-operative radiotherapy for patients with positive mediastinal nodes may improve their overall survival, something which has not been clearly demonstrated in previous studies, said Lynn Wilson, M.D., associate professor, vice chairman and clinical director of the Department of Therapeutic Radiology and senior author of the study.The study analysed data from the Surveillance, Epidemiology and End Results Database (SEER), a national program that collects information on cancer cases from registries that represent 26 percent of the U.S. population. Wilson cautioned that although the findings are encouraging, clinical parameters including technical aspects of the surgery, other contributing illnesses, radiation techniques and radiation dose that may have an impact on the findings are not available from the SEER data.Wilson noted that some previous studies have suggested a detrimental effect on survival for patients receiving postoperative radiotherapy, particularly for patients with earlier stage cancers in which there was no lymph node involvement (N0), or cancer had spread only to the first echelon lymph nodes (N1). For those patients with involvement of mediastinal lymph nodes, the role of post-operative radiotherapy has been controversial, and although data suggested local disease control benefits, overall survival improvements were not clear, Wilson said. The current study confirms the findings regarding the detrimental effects of post-operative radiotherapy on survival for those with N0 or N1 disease, but reveals a significant improvement in survival for those with mediastinal lymph nodes which is a notable finding.(Source: Journal of Clinical Oncology: Yale University: June 2006)