International Early Lung Cancer Action Program (I-ELCAP) patients diagnosed with early-stage lung cancer through low-dose CT (LDCT) screening had high survival rates 20 years later, Ed Susman writes for MedPage Today.

Study details and key findings

The I-ELCAP study, which was designed with goal of advancing LDCT screening, is a multi-institution, multi-national research program that has enrolled over 87,000 participants from more than 80 institutions since it began in 1992.

The current study builds on I-ELCAP researchers' findings from 2006, when they found that patients diagnosed with early-stage disease through LDCT screening had a 10-year lung cancer-specific survival rate of 88%.

According to Claudia Henschke of Mount Sinai Icahn School of Medicine, who reported the study's recent data at the Radiological Society of North America's annual meeting, the 20-year lung cancer-specific survival rate for the 1,285 patients diagnosed with early-stage lung cancer was 80%.

Henschke reported that the 139 participants with non-solid cancerous lung nodules and the 155 patients with nodules of part-solid consistency had 100% lung cancer-specific survival rates, while the 991 participants with solid nodules had a rate of 73%.

For patients with clinical stage IA lung cancers, and for those with resected pathologic stage IA lung cancers that measured 10 millimeters or less the estimated lung cancer-specific survival rate was 86%. Among participants with pathologic stage IA cancers of that measured 10 millimeters or less, the 20-year lung cancer-specific survival rate was 92%.

Commentary

While lung cancer screening is now accepted as lifesaving therapy, "only about 15% of the people who are eligible to undergo screening are being screened," Henschke said, noting that the radiation dose used to screen for lung cancer is roughly 10% of the dose used in mammograms.

"We have made progress in screening, because at the time we started this, there was no screening at all," she said. "But we still have a long way to go."

According to Henschke, there are several possible reasons lung cancer screening is not more common. In particular, she referenced a widespread belief that there is not much that can be done to treat the disease, "and that the treatment is draconian," Susman writes.

"But we are now finding new surgical and radiation treatments that are far less invasive than major lung surgeries," Henschke said. "And we now have the proof that lung-cancer specific survival for 20 years or more is possible for the vast majority of patients."

Moving forward, Henschke and her colleagues will continue tracking the patients in the I-ELCAP study. Notably, they are still starting patients in screening protocols. "We are hoping that our work will allow us to expand the treatment guidelines," she said.

According to the American Lung Association (ALA), the average five-year lung cancer survival rate is currently 18.6%. In addition, ALA noted that fewer than one in five tumors are diagnosed at an early stage, and over half of people with lung cancer die within a year of their diagnosis.

Currently, the U.S. Preventive Services Task Force (USPSTF) recommends annual LDCT screening for individuals aged 50 to 80 who have a 20 pack-year smoking history and either currently smoke or have quit during the previous 15 years. Still, a recent study showed low rates of LDCT screening among patients who are eligible under USPSTF's guidelines.

Max Wintermark of MD Anderson Cancer Center, who was not involved in the study, noted that "when we discuss screening or vaccination, there is always concern about what you are doing, or if what you are doing is worthwhile."

"It is nice to have these kinds of data to guide [patients]...Obviously, if you have lung cancer, this early stage is when you want to be diagnosed, because we can do something about it," he added. (Susman, MedPage Today, 11/29)