Controversy continues regarding screening for lung cancer with low dose computed tomography (LDCT). Last fall, Dr. Lin wrote on the blog about overdiagnosis concerns related to LDCT, and now a new study describes the harms and costs that can result from the diagnostic tests that typically follow positive screening results.
The United States Preventive Services Task Force (USPSTF) gave a B recommendation to screening with LDCT in adults aged 55 to 80 years with at least a 30-pack year tobacco history in 2013, following the National Lung Screening Trial's (NLST) findings that LDCT screening modestly reduced lung cancer mortality. Of note, the American Academy of Family Physicians disagreed with the USPSTF, giving lung cancer screening with LDCT an insufficient evidence rating, both because of its high number needed to treat (312) and its high rate of false positives:
Forty percent of patients screened will have a positive result requiring follow-up, mostly CT scans, although some will require bronchoscopy or thoracotomy. The harms of these follow-up interventions in a setting with a less strict follow-up protocol in the community is not known.
This new study, a retrospective cohort review of over 344,000 patient records, provides information regarding the potential harms of follow-up interventions in a community setting. While the NLST described an estimated complication rate of 8.5-9.8% from invasive diagnostic procedures following a positive LDCT screening result, this larger community study found a much higher complication rate of 22.2-23.8%. Mean complication costs ranged from $6320 for minor complications to $56,845 for major complications.
The Centers for Medicare & Medicaid Services (CMS) mandates shared decision making prior to ordering LDCT for lung cancer screening, but Dr. Lin's post last fall described a 2018 study describing that this shared decision making occurs infrequently and superficially. A 2019 study examining over 8 million Medicare patient records found that only 9% of encounters documented any shared decision making prior to LDCT; interestingly, nearly 40% of patients who did have documented shared decision making opted not to participate in screening.
Shared decision making prior to LDCT is even more imperative given this new data regarding complication rates and costs. Our patients need to understand both LDCT's potential risks and benefits if they are to make a decision about lung cancer screening that aligns with their values.