Surveillance With Computed Tomography After Curative Treatment of Early-Stage Lung Cancer

Abstract

TO THE EDITOR: Furman et al make a persuasive case for limiting intensive follow-up after curative cancer therapy to tumor types for which salvage treatments improve survival. However, their conclusions concerning early-stage non–small-cell lung cancer (NSCLC) disregard the literature that suggests improved outcomes with computed tomography (CT) surveillance may be possible, particularly regarding second primary NSCLC. Using a surveillance program per National Comprehensive Cancer Network recommendations, Lou et al administered postoperative follow-up for 1,294 patients with early-stage NSCLC, using thoracic CT scans every 6 to 12 months for the first 2 years and yearly thereafter. They found a persistent risk of second primary NSCLC of between 3% and 6% per person-years. For patients with early-stage NSCLC treated with stereotactic ablative radiotherapy undergoing the same CT surveillance, second primary NSCLC develops at a similar rate. This reveals that curatively treated survivors of early-stage NSCLC are at a greater risk of lung cancer events than the patients included in the recent National Lung Screening Trial, in which thoracic CT screening improved survival rates by 20% compared with radiographic screenings. Effective surgical salvage for recurrent and second primary NSCLC is possible, with reported 5-year survival rates between 8% and 40% and 25% to 53%, respectively. Although large surgical series have consistently shown that treating recurrences improves survival, this is only feasible in 1% to 4% of patients with isolated local recurrence. This is not the case with CT-detected second primary NSCLC, which are typically small and detected asymptomatically more than 90% of the time. Consequently, such tumors can be resected more than 50% of the time. For patients who are unfit for surgery, stereotactic ablative radiotherapy enables a curative treatment option, achieving 5-year local control rates of approximately 90%, without decreasing patient-reported quality of life. The proponents of intensive surveillance strategies must recognize that the competing risks of death, even in long-term NSCLC survivors, make it difficult to prove improvements in survival. Available literature suggests we should follow surveillance guidelines such as those recommendedbytheAmericanAssociationforThoracicSurgery andsupport ongoing research such as the IFCT-0302 trial in which postsurgical surveillance using radiography is being tested against CT and bronchoscopy, rather than consider NSCLC surveillance futile.