Pattern of Imaging after Lung Cancer Resection. 1992-2005.

RATIONALE: Imaging intensity after lung cancer resection performed with curative intent is unknown.

OBJECTIVES

To describe the pattern and trends in the use of computed tomography (CT) and positron emission tomography (PET) scans in patients after resection of early-stage lung cancer.

METHODS

Retrospective analysis of the linked Surveillance, Epidemiology and End Results (SEER)-Medicare database. Subjects included 8,621 Medicare beneficiaries (age, ≥66 yr) who underwent lung cancer resection with curative intent between 1992 and 2005. A surveillance CT or PET examination was defined as CT or PET imaging performed in an outpatient setting on patients who did not undergo chest radiography in the preceding 30 days.

MEASUREMENTS AND MAIN

RESULTS

Overall, imaging use was higher within the first 2 years versus Years 3-5 after surgical resection. Use of surveillance CT scans increased sharply from 13.7 to 57.3% of those diagnosed in 1996-1997 and 2004-2005, respectively. PET scan use increased threefold, from 6.2% in 2000-2001 to 19.6% in 2004-2005. In multivariable analyses, we observed a 32% increase in the odds of undergoing surveillance CT or PET imaging for every year of diagnosis between 1998 and 2005. There was no substantial decline in the odds of having a surveillance CT or PET scan during each successive follow-up period, suggesting no change in the intensity of surveillance over the first 5 years after surgical resection. The proportion of surveillance CT imaging performed at freestanding imaging centers increased from 18.0% in 1998-1999 to 30.6% in 2004-2005.

CONCLUSIONS

The use of CT and PET imaging for surveillance after curative-intent surgical resection of early-stage lung cancer increased sharply in the United States between 1997-1998 and 2005. In the absence of evidence demonstrating favorable outcomes, this practice was likely driven by prevailing expert opinion embedded in clinical practice guidelines made available during that time. Research is clearly needed to determine the role and optimal approach to surveillance thoracic imaging after surgical resection of lung cancer.