TORONTO – Computed tomography screening among asymptomatic men at high risk for lung cancer reduced lung cancer deaths by a highly statistically significant 26% at 10 years and appeared to reduce lung cancer mortality risk even more in women in the population-based, NELSON trial.
The findings from this large controlled trial encompassing more than 27,000 CT scans in 15,792 individuals support those from the National Lung Screening Trials (), published in 2011, and should “inform and direct future CT screening programs worldwide,” according to Harry de Koning, MD, who presented the findings at the World Conference on Lung Cancer.
Participants were randomized to CT screening at baseline, 1, 3, and 5.5 years after randomization, or to a control group that received usual care. Overall 157 lung cancer deaths occurred in the screening arm vs. 250 in the control arm. Detection rates varied between 0.8% and 1.1% across screenings (0.9% overall), and the positive predictive value of screening was 41%, Dr. de Koning of Erasmus Medical Center, Rotterdam, the Netherlands, said at the meeting sponsored by the International Association for the Study of Lung Cancer.
Notably, 69% of the 243 lung cancers detected by screening were detected at stage 1A or 1B, compared with 10%-12% being detected at stage 4 in about 50% of control patients and based on registry data in the Netherlands.
“There’s huge importance of this early detection in the screening arm,” Dr. de Koning said.
Additionally, an analysis of a subset of those with lung cancer showed a significant threefold increase in surgical treatment among the screened patients vs. those in the control arm who developed lung cancer (67.7% vs. 24.5%), he said.
CT screening reduced the risk of death from lung cancer by 9% to 41% in men over the course of the study, with an overall reduction of 26% at 10 years, and in a smaller subset of women, the rate-ratio of dying from lung cancer varied from 0.39 to 0.61 at different years of follow-up, he said, noting that this suggests a “significant and even larger reduction” in women.
Study participants were individuals aged 50-74 years in the Netherlands and Leuven, Belgium, who were considered at high risk for lung cancer based on responses to a general questionnaire. Participants’ records were linked with national registries with 100% coverage regarding cancer diagnosis and date and cause of death, and medical records for deceased lung cancer patients were reviewed by a blinded expert panel through 2013, and for the remaining study years cause of death as reported by Statistics Netherlands was used. Compliance among those randomized to the screening group was 86%, Dr. de Koning said.
“These findings show that CT screenings are an effective way to assess lung nodules in people at high risk for lung cancer, often leading to detection of suspicious nodules and subsequent surgical intervention at relatively low rates and with few false positives, and can positively increase the chances of cure in this devastating disease,” Dr. de Koning said in a press statement. “It is the second-largest trial in the world, with an even more favorable outcome than the first trial, the NLST, showed. These results should be used to inform and direct future CT screening in the world.”
During a press briefing, in response to a question about whether lung cancer screening should be offered more widely, he said that yes, countries – including the United States – should take note that “now two large-scale trials show large benefit.”
Dr. de Koning reported having no disclosures.