Mortality Risk from Radiation After Surgery for Lung Cancer
An international report in the July 1998 issue of the Lancet argues against radiation therapy following surgery for early stage non-small cell lung cancer (NSCLC). (These findings were subsequently confirmed in a report published in the January 2005 issue of the journal Lung Cancer; see the journal abstract.)
The review and statistical analysis of nine randomized clinical trials totaling 2,128 patients says the exact role of postoperative radiation therapy in the treatment of NSCLC remains unclear. Individually, trials have shown inconclusive and conflicting results and have not been large enough to adequately determine survival benefits, the authors state.
The authors from the Postoperative Radiation Therapy (PORT) Meta-analysis Trialists Group report a 21 percent increase in the risk of death after two years among patients treated with radiation. They say this increase in the risk of death decreased overall survival from 55 percent to 48 percent in the patients studied. This adverse outcome was greatest among patients in disease stages I and II with little or no lymph node involvement. However, an increase in the risk of death among patients with more advanced disease could not be detected.
Worldwide, lung cancers are the main cause of cancer death. More than 500,000 new cases are diagnosed each year, about 80 percent of which are non-small-cell tissue types.
Although about 20 percent of NSCLC's are deemed potentially curable with surgery, survival five years after even "successful" lung operations is about 40 percent. Thus, radiation therapy has been explored to improve the survival picture and to help keep the disease under control.
In the opinion of the authors, such a post-surgery option is "detrimental" to patients with early stage disease and should not be used routinely for them. It may decrease recurrence in the lung but will not improve survival.
"Postoperative chemotherapy may offer a more promising approach than radiotherapy," they state, noting that the use of modern adjuvant chemotherapy may improve survival, as suggested by some of the studies in their review.
A commentary on the article, also published in the Lancet, asserts that the excess deaths due to radiation were the result of radiation pneumonitis, a potentially dangerous lung inflammation that occurs three months to one year after radiotherapy and which mimics bronchial pneumonia. The author notes that the time course of deaths reported in the review article matches that of radiation pneumonitis. If postoperative radiation is used in node-positive NSCLC, he urges that physicians be on the alert for the possibility of pneumonitis, diagnose it promptly and treat it with steroids and antibiotics.
The commentator insists that "the book is not closed" on the use of postoperative radiation in NSCLC. Its benefits for disease that has spread to the lymph nodes need further exploration in more clinical trials.
 Back to Top |
