Spiral computed tomography (CT), a highly sensitive technology that finds early lung cancers, has sparked both renewed interest and controversy in lung cancer screening.
According to the American College of Chest Physicians (ACCP) guidelines (Chest 132:1S-19S, 2007), CT screening has not been shown to reduce mortality in high-risk populations and may do more harm than good. However, the new ACCP guidelines, which recommend that screening be offered only in clinical trials, haven't quelled the ardent debate.
Some screening proponents even urge patients to disregard the ACCP guidelines, contending that CT screening should be a personal choice after conferring with a physician. Moreover, the Lung Cancer Alliance, the disease's only national advocacy group, publicly derided the ACCP guideline for flatly opposing CT screening for those individuals at high-risk for lung cancer.
W. Michael Alberts, MD, chair of the ACCP lung cancer guidelines, told Oncology NEWS International, "There have been no studies that have shown a mortality benefit from spiral CT screening. Given the potential risks involved, we couldn't recommend this procedure at this point."
The ACCP guidelines constitute an endorsement of an ongoing randomized NCI-funded study, the National Lung Screening Trial (NLST). "Our guidelines are evidence-based, and if we see evidence of a mortality benefit from the NLST, then our recommendations would potentially change," Dr. Alberts said.
Proponents of CT screening generally argue that the controversy has been resolved, pointing to the International Early Lung Cancer Action Program (I-ELCAP), a large collaborative study led by Claudia I. Henschke, MD, PhD, of Weill Medical College of Cornell University.
I-ELCAP investigators concluded that annual spiral CT can detect clinical stage I lung cancer in a high proportion of persons when it is curable by surgery (N Engl J Med 355:1763-1771, 2006). Among patients diagnosed at baseline CT scan with stage I cancer and who received treatment, 92% were alive at 10 years.