Cons: long-term CT-scan follow-up is not the standard of care in patients curatively treated for an early stage non-small cell lung cancer

About 25% of patients with early stage (I, II, IIIA non-N2) non-small cell lung cancer (NSCLC) qualify for a treatment with curative intent, consisting of either radical surgical resection or radical radiotherapy. The former consists of at least an anatomical lobectomy, the latter is nowadays mainly given at ablative doses with stereotactic techniques (SABR). Radically treated patients may develop either locally or distantly relapsing lung cancer, or a second primary (lung) cancer. Besides, they retain a significant excess conditional mortality with an increasing relative contribution of cardiovascular and respiratory co-morbidity (1). Recurrence dynamics of resected early-stage NSCLC displays a multipeak pattern, which supports the hypothesis of a metastasis growth model previously described for early-stage breast cancer (2). An initial surge in the hazard rate 9 months after surgery, is followed by two smaller peaks at the end of the second and fourth years, respectively (Figure 1). This pattern is dominated by distant metastatic events which decrease over time and are virtually absent after 5 years. Two distinguishable peaks are noted for local recurrence in the first and second years, but this is rare thereafter. The risk of local or distant recurrence is 10-38%, mainly dependent of stage and highest in pII-III NSCLC. This risk can be moderately reduced by the administration of postoperative platinum-based chemotherapy, with an average increase in 5 year survival of 5% (3). In contrast, the hazard rate for second primary lung cancer exhibits a more uniform pattern over time, is 1% to 4% per patient per year in most series (4) and increases even after 5 years. The median time interval between the two tumours is 14.5 months (5,6). Lastly, these patients are at risk of developing a second primary nonrespiratory cancer: the most frequently diagnosed tumours are located in the head and neck and the urinary tract.