‘Inconclusive evidence’ of link between intensity of lung nodule evaluation, outcomes

In a new study, researchers concluded there is “inconclusive evidence” of an association between less intensive diagnostic evaluations of lung nodules and more advanced stage at lung cancer diagnosis compared with guideline-recommended care.

“Practice guidelines recommend using varying intensities of diagnostic evaluation for lung nodules that are based on an individual’s underlying lung cancer risk factors (eg, smoking) and nodule characteristics (eg, size),” Farhood Farjah, MD, MPH, thoracic surgeon, scientist and professor in the department of surgery at the University of Washington, Seattle, and colleagues wrote in JAMA Internal Medicine.

The researchers conducted a comparative effectiveness study that assessed 5,057 health plan enrollees (mean age, 67 years; 55% women) with incidental lung nodules detected from 2005 to 2015 at Kaiser Permanente Washington in Seattle and Marshfield Clinic in Wisconsin. Patients had no high suspicion of infection, no history of malignant neoplasm and no evidence of advanced lung cancer.

Researchers compared use of the 2005 Fleischner Society guidelines with less intensive evaluation and more intensive evaluation. Less intensive evaluations did not involve recommended testing and included longer surveillance intervals or less invasive testing than recommended. More intensive evaluations included testing even when guidelines recommended no further testing, shorter surveillance intervals or more invasive testing than recommended.

The primary outcome was the number of patients with lung cancer who had stage III or IV disease, radiation exposure, procedure-related adverse events and health expenditures 2 years after nodules were detected.

Thirty-eight percent of patients received guideline-concordant evaluations, 37% received less intensive diagnostic evaluations and 25% received more intensive diagnostic evaluations.

Less intensive diagnostic evaluations were associated with lower mean radiation exposure (–9.5 millisievert [mSv]; 95% CI, –10.3 to –8.7), lower mean health expenditures (–$10,916; 95% CI, –16,112 to – 5,719) and fewer procedure-related adverse events (risk difference, –5.9%; 95% CI, –7.2 to –4.6) compared with guideline-concordant evaluations. There was no difference in stage III or IV disease among those diagnosed with lung cancer (risk difference, 4.6%; 95% CI, –22 to 31), according to the results.

Researchers reported higher mean radiation exposure (6.8 mSv; 95% CI, 5.8-7.8), higher mean health expenditures ($20,132; 95% CI, 14,398-25,868) and more procedure-related adverse events (risk difference, 8.1%; 95% CI, 5.6-11) in those who received more intensive diagnostic evaluations compared with guideline-concordant evaluations. Again, there was no difference in stage III or IV disease observed (risk difference, –0.5%; 95% CI, –28 to 27), according to the results.

In the patients with lung cancer, the frequency of stage III or IV disease was 42% in those who received guideline-concordant evaluations, 47% in those who received less intensive evaluations and 43% in those who received more intensive evaluations. In a sensitivity analysis accounting for all possible outcomes in the overall cohort, there was no difference in the relative risk for stage III or IV disease between those who underwent less intensive vs. guideline-concordant evaluations (RR = 1.21; 95% CI, 0.44-3.34) or between those who underwent more intensive vs. guideline-concordant evaluations (RR = 1.01; 95% CI, 0.4-2.52).

“Findings from this study underscore the need to increase the level of evidence that supports current guideline recommendations and to decrease unnecessarily intensive diagnostic evaluations of lung nodules,” the researchers wrote.