Abstract and Introduction
Abstract
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.
Introduction
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.[6] 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.[7] However, these benefits must be weighed against the potential harms of surveilling too frequently [ie, "scanxiety",[8] false positives, unwarranted procedures, considerable health-care costs, etc].[7]
Current guidelines recommend cross-sectional, computed tomography (CT) imaging for lung cancer surveillance.[7] 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.[8] 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.[7] 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[15] and retrospective[16] 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.[17] 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.[20]
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
