Lung Cancer Death Rate Not Lowered by X-rays
The rate of death from lung cancer is not lowered by annual chest x-ray screening compared with usual care, reveals a study of published in the online edition of the Journal of the American Medical Association and slated to appear in the November 2 print edition.
Martin M. Oken, MD, of the University of Minnesota in Minneapolis, Minnesota and his colleagues examined the effect on mortality of screening for lung cancer using chest x-ray in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. In their randomized, controlled trial of 154,901 patients ages 55 through 74, 77,445 individuals underwent chest x-ray screenings every year for four years, while 77,456 were subjected to usual care.
About 50.5% of participants in each group were female; about 45% had never smoked; 42% were former smokers; and 10% were current smokers. All diagnosed cancers, deaths and causes of death were ascertained through the earlier of 13 years of follow-up or until December 31, 2009.
A total of 1,696 lung cancers were detected in the intervention group and 1,620, in the usual care group
During the 13-year study period. About 41% of patients from each group were diagnosed with adenocarcinoma; 20%, with squamous cell carcinoma; 14%, with small cell carcinoma; 5%, with large cell carcinoma; and 20%, with other non-small-cell lung cancer.
Moreover, for the total 13-year follow-up period, a similar number of lung cancer deaths were observed--1,213 in the intervention group and 1,230 in the usual care group.
Also part of the study was an ancillary analysis of the subset of PLCO participants who would have been eligible for the National Lung Screening Trial (NLST); the subset comprised 15,183 subjects in the chest x-ray group and 15,138 in the usual care group.
Similar rates of lung cancer diagnoses and lung cancer deaths were identified. Of patients in the chest x-ray group, 518 were diagnosed with lung cancer and 316 deaths occurred. The usual care group had 520 lung cancer cases and 334 deaths.
“The randomized groups in PLCO were comparable at baseline, there was relatively high screening adherence in the intervention group and low contamination in the usual care group, and the treatment distributions across the groups were similar,” the researchers write. "Therefore, these findings provide good evidence that there is not a substantial lung cancer mortality benefit from lung cancer screening with four annual chest radiographs."
To read the abstract, click here:
http://jama.ama-assn.org/content/early/2011/10/20/jama.2011.1591.abstract