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Some Physicians Knowingly Order Guideline-Discordant Lung Cancer Screening

Key findings

  • This study investigated how often providers at Massachusetts General Hospital knowingly order lung cancer screening examinations outside insurance coverage criteria and U.S. guidelines despite receiving an electronic alert at the point of order entry
  • Guideline-discordant screening CT occurred but was uncommon, accounting for 2% of lung cancer screening examinations performed over the one-year study period
  • 45% of 42 guideline-discordant screening exams were for patients who fell outside age and smoking history criteria of all U.S. guidelines; 74% were for patients who fell outside all guidelines except those of the American Association for Thoracic Surgery
  • 14% of patients screened had never smoked
  • Radiologists should consider adapting screening CT reports for patients who do not meet criteria for lung cancer screening and support both providers and patients in assessing lung cancer risk and screening appropriateness

Medicare recommends low-dose CT for lung cancer screening (LCS) only for former smokers ages 55–77 who have a ≥30-pack-year smoking history and quit smoking ≤15 years previously. Except for the stopping age, these were the inclusion criteria of the National Lung Screening trial, published in 2011 in The New England Journal of Medicine. With minor variations, other U.S. guidelines for LCS are similar.

The benefits and harms of LCS for individuals with lighter smoking histories and for those with other lung cancer risk factors are uncertain. However, Gary X. Wang, MD, PhD, diagnostic radiologist in the Department of Radiology at Massachusetts General Hospital, Efren J. Flores, MD, an officer of Radiology Community Health Improvement and Equity at Mass General, and colleagues have documented that some providers knowingly request LCS for patients who don't meet suggested criteria.

The researchers report their findings in the Journal of the American College of Radiology, along with recommendations for radiologists about responding to orders for guideline-discordant LCS.

Study Methods

In November 2018, Mass General integrated a best practices advisory alert about LCS into the electronic medical record system. The alert is triggered when providers attempt to order screening CT for patients outside of Medicare criteria. If providers choose to override the alert and order the exam, then they are asked to give indications for LCS, although that isn't mandatory.

The researchers determined that between November 2018 and December 2019, providers ordered LCS for 55 patients after overriding the alerts. 13 did not undergo screening during the study period.

Screening Outside Medicare Guidelines

Of the 42 patients remaining:

  • 12 (29%) were younger than 55
  • 6 (14%) were older than 77
  • 6 (14%) had never smoked
  • 17 (41%) had quit >15 years earlier
  • 13 (31%) had smoked <30 pack-years
  • 12 (29%) fell outside more than one criterion

Guideline-discordant screening CT was ordered by 31 providers and accounted for 1.9% of all 2,248 screening CT examinations performed during the study period.

Screening Outside Additional Guidelines

No U.S. guidelines support screening for never smokers without personal histories of lung cancer, smokers older than 80 or smokers younger than 50 and/or with <20-pack-year smoking histories, even if additional lung cancer risk factors are present. Yet in this cohort LCS was ordered for:

  • 19 (45%) patients who fell outside the age and smoking history criteria of all U.S. guidelines
  • 31 patients (74%) who fell outside all U.S. guidelines except those of the American Association for Thoracic Surgery, which recommends screening of all former smokers ages 55 to 79 who have ≥30-pack-year smoking histories, regardless of the number of years since quitting

Indications for Guideline-Discordant Screening

The reasons providers gave for overriding alerts were:

  • Family history of lung cancer—nine patients (21%)
  • Occupational exposure to carcinogens as a firefighter—four (10%)
  • Thoracic radiation therapy—two (5%)
  • Asbestos exposure—one (2%)
  • Elevated lung cancer serum markers per patient self-report of laboratory tests performed outside the U.S.—one (2%)
  • No information—25 (60%)

Recommendations for Radiologists

A qualitative study of clinical notes showed that perceptions of lung cancer risk from both patients and providers contributed to guideline-discordant screening use. Specially trained personnel associated with LCS programs, such as from pulmonary nodule clinics, may be able to guide both groups in making individualized decisions about risk and appropriateness of screening.

Radiologists interpreting screening examinations should try to stay aware of patients who do not meet screening criteria. In these cases, rather than use Lung-RADS for reporting, it may be more appropriate to manage CT findings according to the Fleischner Society guidelines published in Radiology or follow usual institutional practice for reporting incidental pulmonary findings on routine chest CT.

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