Patients who have undergone curative treatment for early-stage non-small cell lung cancer (NSCLC) are at significant risk for disease recurrence and second tumors, and thus periodic follow-up CT scans have been a part of clinical care pathways. However, prospective studies have yet to show a survival benefit for this approach.
In the prospective IFCT03-02 study, CT-based follow-up detected more recurrences than routine follow-up with chest x-rays alone (recurrences in 32.6% vs. 27.7%, respectively; second primary lung cancers in 4.5% vs. 3.0% respectively).1 CT-detected disease in IFCT03-02 was more frequently asymptomatic as well as more amenable to curative-intent treatment; yet no improvement in survival was observed.
Recent landmark studies in patients with tumors measuring 2 cm or smaller underscore the magnitude of the problem. For example, CALGB 140503 reported a locoregional recurrence rate of 13.4% after sublobar resection and 10.0% after lobectomy, with a new primary lung cancer comprising 18% of all recurrences after a sublobar resection.2
These findings make the conclusion of a recent retrospective US Veterans Administration study to extend the time intervals between scans in order to decrease patient anxiety somewhat inappropriate,3 a point well-articulated by two patient advocates in recent ILCN patient perspectives. Indeed, patient advocate Laura Floyd makes a telling comment in her perspective, saying “a study that finds no overall survival benefit to scans doesn’t tell me that scans may be unnecessary—it tells me that the medical system still hasn’t figured out how to use imaging to improve prognosis for even the earliest stages of lung cancer.”
Developments in artificial intelligence suggest that it may be possible to use CT scans to provide additional information about future lung cancer risk. The recent Sybil study used a deep-learning model to analyze a single baseline CT scan from National Lung Screening Trial to predict lung cancer risk for the next one to six years.4 Extending this line of research to post-surgical patients, together with other developments such as circulating tumor DNA, may facilitate the development of more tailored follow-up strategies that may improve overall survival in this patient group.
References
- 1. Westeel V, Foucher P, Scherpereel A, et al. Chest CT scan plus x-ray versus chest x-ray for the follow-up of completely resected non-small-cell lung cancer (IFCT-0302): a multicentre, open-label, randomised, phase 3 trial. Lancet Oncol. 2022;23(9):1180-1188. doi:10.1016/S1470-2045(22)00451-X
- 2. Altorki N, Wang X, Kozono D, et al. Lobar or Sublobar Resection for Peripheral Stage IA Non-Small-Cell Lung Cancer. N Engl J Med. 2023;388(6):489-498. doi:10.1056/NEJMoa2212083
- 3. Heiden BT, Eaton DB, Chang SH, et al. Association between imaging surveillance frequency and outcomes following surgical treatment of early-stage lung cancer [published online ahead of print, 2022 Nov 29]. J Natl Cancer Inst. 2022;djac208. doi:10.1093/jnci/djac208
- 4. Mikhael PG, Wohlwend J, Yala A, et al. Sybil: A Validated Deep Learning Model to Predict Future Lung Cancer Risk From a Single Low-Dose Chest Computed Tomography [published online ahead of print, 2023 Jan 12]. J Clin Oncol. 2023;JCO2201345.
