False Positives Low for CT Lung Cancer Screening

Addressing concerns that CT imaging to screen for lung cancer would increase the number of false-positives, researchers found it actually resulted in a low rate for benign nodules. A study published in the current issue of the American Journal of Roentgenology looked at nearly 5,000 high-risk current and former smokers who had CT of the chest between 2003 and 2009. Biopsies were performed on 127 patients with an overall false-positive rate of 0.42%. An earlier National Cancer Institute study published in the New England Journal of Medicine had found that annual CT screening of current or former smokers age 55 to 74 years old could reduce lung cancer deaths by 20 percent over similar screening with chest radiography. However, the concern was that low-dose CT screening might be too sensitive a test and could lead to too many unnecessary biopsies, which has its own risks. Last year, WellPoint became the first insurer to cover CT screening to look for lung cancer in patients that had smoked heavily for more than 30 years. Radiology departments at many major hospitals — University of Pittsburgh Medical Center, Swedish Medical Center in Denver, Abbott Northwestern Hospital in Minneapolis, Rhode Island Hospital in Providence, Pomona Valley Hospital Medical Center in California and the University of California San Francisco, just to name a few — also offer below-cost chest CT scans for patients who can pay cash for the test. However, this practice has been controversial. Last year, a Kaiser Health News report looked at the marketing of for-cash low-dose chest CTs and pointed out that medical centers that offer this may make up the money they lose on the CTs by also providing follow-up testing and cancer treatment to those patients who test positive.