Low-Dose CT Detects More Lung Cancers, Lowers Mortality

May 23, 2013

Study confirms earlier findings that low-dose CT detects more lung cancer than chest X-rays and lowers mortality from lung cancer.

Lung cancer screening with low-dose CT detects more than twice the number of early-stage cancers as does chest X-ray, according to a study published in the New England Journal of Medicine.

The article reports a follow-up of a 2011 NEJM study that reported on the National Lung Screening Trial (NLST) results.

Researchers randomized 53,454 participants who were enrolled in the NLST to either low-dose CT (26,722) or single-view posteroanterior chest radiography (26,732). The goal was to assess the usefulness of LDCT in detecting early lung cancer. The original findings reported a 20 percent reduction in lung cancer deaths among high-risk patients who were screened with LDCT over those who were screened by X-ray.

Today’s findings report that the LDCT was superior in other aspects as well. More LDCT patients had positive results than those who had chest X-rays (7,191 versus 2,387, respectively). More LDCT patients had diagnostic procedures (6,369 versus 2176), more had biopsies and other procedures (297 versus 121), and more lung cancers were found among the patients in the LDCT group than the CXR group during the first NLST screening round (292 versus 190, respectively).

The researchers were encouraged by the high rate of compliance in performing the LDCT examination as specified in the research protocol across the 33 participating imaging facilities.

“The sites complied with the low-dose CT imaging protocol specifications in 95.5 percent of all studies performed, which is outstanding considering the many thousands of scans performed,” Denise R. Aberle, MD, said in a release. Aberle is the national principal investigator for NLST ACRIN and site co-principal investigator for the UCLA NLST team.

These findings may make it easier for physicians to discuss the facts about the testing results with patients who are similar to those who participated in the trial.

“The results also caution against making blanket lung cancer screening recommendations, because each person’s trade-off between the risk of having an unnecessary procedures and the fear of dying of lung cancer is uniquely individual,” said Timothy Church, PhD, a biostatistician and professor in the School of Public Health at the University of Minnesota who has been involved in the NLST design, implementation, and analysis.