Delayed Lung Cancer Screening Trial to Begin Enrollment 50,000 Subjects

BETHESDA, Maryland—A lung cancer screening trial supported by the National Cancer Institute (NCI) that will compare spiral CT and standard chest x-ray is back on track after being delayed for several months. Andrew von Eschenbach, MD, ordered a review of the planned 50,000-subject study, expected to cost about $200 million, soon after becoming NCI director in January.

"It is obviously a very significant commitment with regard to the financial investment," Dr. von Eschenbach told the National Cancer Advisory Board. "Before launching the study, I wanted to be absolutely certain that we had exercised due diligence to ensure that all issues were thoroughly addressed."

A major result of the review will be an expansion of the number of research centers participating in the National Lung Screening Trial (NLST) to 30 from the originally intended 20 sites. Enrollment should begin later this year.

As part of the review, NCI discussed the trial plan and protocol with researchers who will conduct it and with people in the cancer community who had expressed concerns about many of the details of the 8-year study. "It was an opportunity to do some additional fine tuning of the study that I think will enhance its impact and increase our confidence level that it will yield appropriate, meaningful results, and do it in a timely fashion," Dr. von Eschenbach said.

The additional 10 research sites "will help us to front-load the study as far as accrual in a much more effective way," he added. "The quicker we can accrue to this trial, the more people we can enter at the very beginning, the more likely it is that we will get more meaningful results in an early period of time. And that, in turn, will translate into very significant cost savings."

NCI has also removed accrual allocations from the study in an effort to speed up recruitment. Each center can enroll as many participants as possible until the accrual goal is met. In addition, the American Cancer Society has pledged $1 million a year for the first 5 years of the NLST to help NCI cover the study’s costs. The Institute is also in discussions with the American Legacy Foundation "that may result in some additional financial contributions to the study," Dr. von Eschenbach said.

Both spiral CT, also known as helical CT, and chest x-rays can detect lung cancer. Several studies in the United States and Japan have shown that spiral CT can detect tumors well below 1 cm. The smallest tumors picked up by standard chest x-rays range from 1 to 2 cm. However, there is no conclusive evidence that screening or early detection reduces a patient’s risk of dying of lung cancer.

According to NCI, the NLST will have the statistical power to determine a 20% or greater decrease in mortality—and which of the two technologies is better—if it meets its enrollment goal.

Study Protocol

The trial, a randomized, controlled study, will screen current and former long-term smokers. Following their first screening, participants will be screened again 1 and 2 years later. Researchers will then contact participants yearly by telephone or mail to monitor their health status.

Those with screening results that show an abnormality that might be cancer will be notified, as will their primary care physicians, and will be encouraged to consult an oncologist. A list of cancer specialists will be provided on request. Follow-up tests may be done at the study center. Although the screenings are free, the cost of further evaluations is the responsibility of the patient.

The NLST is open to current or former heavy smokers between the ages of 55 and 74. Other eligibility requirements include good health without a history of lung cancer, and the volunteer must not have been diagnosed or treated for any cancer other than nonmelanoma skin cancer within the past 5 years. Participants may not be enrolled in any other cancer screening or prevention trial or have had a CT scan of the chest or lungs in the previous 18 months.

Additional information on the NLST in English or Spanish is available by calling 1-800-422-6237 between 9 AM and 4:30 PM local time.