Lung Cancer Screening Complications

In the landmark National Lung Screening Trial, low-dose computed tomography (LDCT) lowered lung cancer–specific mortality among smokers (number needed to screen, 320 to prevent 1 death; NEJM JW Gen Med Aug 1 2011 and N Engl J Med 2011; 365:395). But the tradeoff is that many screened patients require additional imaging or procedures, and some develop procedural complications. Investigators retrospectively assessed more than 9000 patients from five large U.S. healthcare systems who received LDCT screening in routine clinical practice. Sixteen percent of LDCTs showed abnormalities, and 1.5% of patients received diagnoses of lung cancer within 12 months.

Study findings included the following:

• LDCT's sensitivity was 93%, specificity was 84%, positive predictive value was 10%, and negative predictive value was 99.8%.
• Among screened patients, one third underwent downstream imaging (i.e., additional CT, magnetic resonance imaging, or positron-emission tomography), and 1 in 35 patients underwent invasive procedures (i.e., biopsy, bronchoscopy, mediastinoscopy, thoracoscopy, thoracentesis, or thoracotomy).
• Compared with complication rates in the National Lung Screening Trial, this real-world study had approximately twice the rate of procedural complications (31% vs. 18%) and major complications (i.e., acute respiratory failure, lung collapse or cardiac arrest; 21% vs. 9%).