Abstract and Introduction
Background: Recent studies have suggested that more frequent postoperative surveillance imaging via computed tomography following lung cancer resection may not improve outcomes. We sought to validate these findings using a uniquely compiled dataset from the Veterans Health Administration, the largest integrated health-care system in the United States.
Methods: We performed a retrospective cohort study of veterans with pathologic stage I non-small cell lung cancer receiving surgery (2006–2016). We assessed the relationship between surveillance frequency (chest computed tomography scans within 2 years after surgery) and recurrence-free survival and overall survival.
Results: Among 6171 patients, 3047 (49.4%) and 3124 (50.6%) underwent low-frequency (<2 scans per year; every 6–12 months) and high-frequency (≥2 scans per year; every 3–6 months) surveillance, respectively. Factors associated with high-frequency surveillance included being a former smoker (vs current; adjusted odds ratio [aOR] = 1.18, 95% confidence interval [CI] = 1.05 to 1.33), receiving a wedge resection (vs lobectomy; aOR = 1.21, 95% CI = 1.05 to 1.39), and having follow-up with an oncologist (aOR = 1.58, 95% CI = 1.42 to 1.77), whereas African American race was associated with low-frequency surveillance (vs White race; aOR = 0.64, 95% CI = 0.54 to 0.75). With a median (interquartile range) follow-up of 7.3 (3.4–12.5) years, recurrence was detected in 1360 (22.0%) patients. High-frequency surveillance was not associated with longer recurrence-free survival (adjusted hazard ratio = 0.93, 95% CI = 0.83 to 1.04, P = .22) or overall survival (adjusted hazard ratio = 1.04, 95% CI = 0.96 to 1.12, P = .35).
Conclusions: We found that high-frequency surveillance does not improve outcomes in surgically treated stage I non-small cell lung cancer. Future lung cancer treatment guidelines should consider less frequent surveillance imaging in patients with stage I disease.
Surgical resection remains the standard treatment for early-stage non-small cell lung cancer (NSCLC), the leading cause of cancer-related mortality in the United States.[1,2] Early-stage lung cancer is unique compared with several other malignancies in that, even after curative-intent resection, recurrence is common, occurring in 20% to 50% of patients within 5 years.[3–5] Therefore, surveillance (ie, regimented follow-up imaging in asymptomatic patients) is a routine component of postoperative care, with the hope that earlier detection will allow for more aggressive treatments and better outcomes among patients who recur. In addition to detecting recurrence, surveillance imaging can also monitor for new primary malignancies, screen for treatment side effects, and alleviate patient anxiety about recurrence. However, these benefits must be weighed against the potential harms of surveilling too frequently [ie, "scanxiety", false positives, unwarranted procedures, considerable health-care costs, etc].
Current guidelines recommend cross-sectional, computed tomography (CT) imaging for lung cancer surveillance. Indeed, the long-awaited IFCT-0302 recently demonstrated that surveillance CT was superior to chest x-ray for detecting cancer recurrence and second primary malignancies, though overall survival was similar between the groups. However, guidelines conflict on the optimal frequency of CT surveillance, with most suggesting 6-month intervals between scans.[3,9–12] This frequency is typically maintained for 2 to 3 years after resection, during which the risk of recurrence is highest; beyond that period, annual surveillance imaging is adopted given the continued risk of second primary cancers. However, some recent studies have suggested that more frequent surveillance imaging after cancer surgery may not improve outcomes. For example, in lung cancer, a recent analysis demonstrated that more frequent surveillance (based on the length of time between surgery and the initial CT scan after surgery) was not associated with improved outcomes.[13,14] These findings, although important, were limited by the age of the dataset, nonuniform health insurance coverage (which can affect access to care), stage heterogeneity (I-III), and the absence of cause-specific survival models.[13,14] In colorectal cancer, both prospective and retrospective studies similarly have found that more frequent surveillance (either via imaging or biochemical testing) does not improve outcomes. These findings have not been validated in a larger, modern cohort.
The Veterans Health Administration (VHA) is the largest integrated health-care system in the United States. As such, the VHA provides veterans with universal access to regular follow-up at little or no cost,[18,19] hence mitigating several of the methodological limitations and biases that other datasets have in terms of analyzing surveillance strategies.
In this study, we sought to examine the association between surveillance frequency and oncologic outcomes in pathologic stage I NSCLC following surgical treatment. We hypothesized that more frequent surveillance was not associated with improved recurrence-free survival or overall survival.
J Natl Cancer Inst. 2023;115(3):303-310. © 2023 Oxford University Press