What's New
Lung Cancer: Do Early Screening, Treatment Yield Better Outcomes?
A CT scan of the lung. NewYork-Presbyterian Hospital researchers are investigating the efficacy of low-dose CT in
lung cancer screening.
Alandmark study in The New England Journal of Medicine has shown that early detection of lung cancer can favorably change outcomes (2006;355:1763-1771).
The study, a multinational collaboration published under the auspices of the International Early Lung Cancer Action Program (I-ELCAP), was initiated by Weill Cornell investigators at NewYork-Presbyterian Hospital under the direction of Claudia I. Henschke, MD, PhD, principal investigator.
Dr. Henschke also chaired the Writing Committee of I-ELCAP; the other members were David Yankelevitz, MD, Daniel Libby, MD, Mark Pasmantier, MD, James Smith, MD, and Olli Miettinen, MD, PhD.
From the initiation of I-ELCAP, Columbia investigators led by John Austin, MD, have been key collaborators.
"We had previously demonstrated that screening is effective for early detection of lung cancer.
The importance of this study is that it confirmed that early [lung cancer] detection, which can lead to early treatment, markedly increases the likelihood of survival," said Dr. Henschke.
The study, which employed low-dose, spiral computed tomography (CT) to identify noncalcified nodules for biopsy, opens the door for further efforts to expand lung cancer screening.
In the study, 31,567 asymptomatic men and women were screened.
Criteria included age older than 40 years and having a risk factor for lung cancer—most often a history of cigarette smoking, but also occupational exposure to such carcinogenic
substances as asbestos and radon, or exposure to secondhand smoke.
Although these risk factors were the focus of I-ELCAP, they may not be the only ones used for screening now that there is evidence that screening can improve outcomes.
New research protocols are being designed to look at a variety of other populations, such as a population of flight attendants who never smoked but who had previous occupational exposure to cigarette smoke.
"One of the important questions to address in future studies is how frequently to screen patients in the highest risk groups in order to identify lung cancer at its earliest stages," Dr. Henschke said.
Although cost-efficacy will have to be calculated according to risk status, current screening protocols have already been shown to be cost effective in high-risk groups, she said.
"This is clearly a critical avenue for research," said Dr. Austin.
He noted that NewYork-Presbyterian Hospital/Columbia University Medical Center entered more than 500 patients into the I-ELCAP study, and results in this subpopulation mirrored the overall results.
He agreed that the new data very much weaken the arguments of the skeptics about the importance of early detection for improving outcomes.
"We also have very sophisticated treatment protocols and are involved in trials of several different modalities in lung cancer, but the best results are going to be achieved in those who are diagnosed at the earliest possible stage," Dr. Austin said.
The evidence that screening can detect small lesions in the lung has opened up a range of research involving the collaboration of several innovators in radiology.
Not least among these is Dr. Yankelevitz, who also served on the Writing Committee of I-ELCAP and has led or contributed to a number of studies designed to identify prognostic factors at the time of detection, including early detection.
In current or former smokers aged 60 years or older, the baseline detection rate in the original Early Lung Cancer Action Program study was 2.7%.
In comparison, the baseline yield for breast cancer in women over the age of 40 who are screened with mammography has been 1% or less.
Early detection is likely to be even more important in lung cancer than in breast cancer because mortality is higher, reaching approximately 85% currently.
Low-dose CT scan can be provided for less than $300 per case.
Because about 15% of lung cancer cases in the United States occur in never-smokers, periodic screening of all middle-aged or older adults would be an optimal step in lung cancer prevention.
However, researchers must define populations in which screening is both practical and cost-effective.
"The economic analyses will be important in determining appropriate use of healthcare dollars for lung cancer screening.
We are continuing to gather the data to recommend rational choices," Dr. Austin said.
John Austin, MD, is Director of Thoracic Imaging at NewYork-Presbyterian Hospital/Columbia University Medical Center and is Professor of Radiology at Columbia University College of Physicians and Surgeons.
Claudia I. Henschke, MD, PhD, is Attending Radiologist at NewYork-Presbyterian Hospital/Weill Cornell Medical Center and is Professor of Radiology in Cardiothoracic Surgery at Weill Cornell Medical College.
David F. Yankelevitz, MD, is Attending Radiologist at NewYork-Presbyterian Hospital/Weill Cornell Medical Center and is Professor of Radiology in Cardiothoracic Surgery at Weill Cornell Medical College.
|
