Overuse and Underuse of Recommended Imaging for Lung Cancer Staging in National VA Cohort
In a study reported in the Journal of Clinical Oncology, Backhus et al found that imaging guideline recommendations for staging of locally advanced lung cancer were often not followed in a national Veterans Affairs (VA) cohort.
Study Details
The study involved 3,808 patients with stage IIB, IIIA, or IIIB lung cancer in the national VA Central Cancer Registry who were diagnosed between 2004 and 2007 and who were linked to VA and Medicare databases.
Appropriate imaging was based on National Comprehensive Cancer Network and American College of Radiology Appropriateness Criteria and was defined as receipt of brain magnetic resonance imaging or brain computed tomography (CT) scan and positron-emission tomography (PET) imaging, including PET or combined PET-CT imaging, during the study window. Overuse was defined as performance of both bone scintigraphy and PET imaging within the study window. All imaging was assessed during the period 180 days through 180 days after diagnosis.
Adherence Rates
Overall, guideline-recommended imaging was performed in 75% of patients for brain imaging and 60% of patients for PET imaging. Overuse, consisting of bone scintigraphy and PET, occurred in 25% of patients.
Factors Associated With Imaging
On multivariate analysis, guideline-recommended brain imaging was associated with more advanced clinical stage (stage IIIA: odds ratio [OR] = 1.67, P < .01; stage IIIB: OR = 1.48, P < .01), later year of diagnosis (2006: OR = 1.57, P < .01; 2007: OR = 1.54, P = .02), and younger age (> 75 years: OR = 0.61, P < .01; age 70–75 years: OR = 0.69, P < .01). Higher rates of recommended PET imaging were associated with later years of diagnosis (2006: OR = 1.91, P < .01; 2007: OR = 2.7, P < .01), and lower rates were associated with black race (OR = 0.74, P < .01), more advanced clinical stage (stage IIIA: OR = 0.73, P < .01; stage IIIB: OR = 0.51, P = .03), and medical school affiliation (OR = 0.46, P = .03). Overuse of bone scintigraphy and PET was associated with earlier year of diagnosis (2005: OR = 1.36, P = .04) and younger age (> 75 years: OR = 0.75, P = .02.
Geographic Variation
In unadjusted analysis, adherence to brain imaging guidelines was highest in New England (93%) and lowest in the Mississippi region (69%). Appropriate PET imaging was greatest in the Pacific (78%) and New England regions (71%) and lowest in Mississippi and Mid-Atlantic regions (46% in both). Overuse of bone scintigraphy and PET was most common in the Great Lakes (32%) and Great Basin regions (30%) and least common in the Mississippi and South Plains regions (16% in both).
The investigators concluded: “Receipt of guideline-recommended imaging is not universal. PET appears to be underused overall, whereas [bone scintigraphy] demonstrates continued overuse. Wide regional variation suggests that these findings could be the result of local practice patterns, which may be amenable to provider education efforts such as Choosing Wisely.”
Leah M. Backhus, MD, of University of Washington, Seattle, is the corresponding author for the Journal of Clinical Oncology article.
The study was supported by the Department of Veterans Affairs and National Cancer Institute. The authors indicated no potential conflicts of interest.
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