@ERSpublicationsThe second lung resection is a valuable option for post-operative lung cancer recurrence http://ow.ly/U8z3cSurgical treatment offers the best chances for long-term survival in patients with primary nonsmall cell lung cancer (NSCLC). However, long-term survival after surgery remains less than 50%, mostly due to a 30-77% rate of tumour recurrence. Unlike the distant type of recurrence that is treated nonsurgically in the vast majority of patients, local or loco-regional recurrence, which occurs in 4.6-24% of patients after complete resection (∼80% of cases in the first 2 years) [1], raises several concerns related to the optimal therapeutic approach.Unfortunately, literature data are not always helpful in practice. For example, 5-year loco-regional recurrence rates are between 15 and 38.5% [2], and the incidence of local recurrence in early-stage lung cancer of 10-15% [3], or a mean disease-free interval of 14.1-19.8 months, that is similar to distant recurrent disease [4]. Failure to demonstrate the advantage of complete lymphadenectomy over nodal sampling in terms of local recurrence or survival in patients operated for T1-2, N0 or T1-2, N1 disease, makes the clinical approach more complex [5]. Moreover, the impact of intensified follow-up on overall survival or local recurrence detection could not be clearly demonstrated. In ∼50-67% of patients, recurrence will appear before a scheduled control because of the onset of symptoms [6].Finally, switching to seventh edition of the TNM (tumour, node, metastasis) staging system automatically led to the stage migration, reaching 21% in some studies. The only study of the role of computed tomography (CT) in post-operative recurrence detection demonstrated a high negative predictive value of 95%, but a positive predictive value of only 53% (94% sensitivity and 87% specificity) [7]. For positron emission tomography, although it is more sensitive than CT in detecting recurrent tumours (97-100%), variations of the cut-off values for the standardised uptake value (⩾4.5-⩾10) make its clinical application difficult, together with its specificity (62-100%) that is lower than for CT.The role of prognostic factors after surgery is more evidence-based, owing to awareness of the poor 5-year survival of patients in stages IA and IB (73% and 58%, respectively). This also applies to the high recurrence rate in patients with stage I after complete resection (25-50%) [8]. The results of these studies really helped to identify patients who would probably benefit from adjuvant therapy.Among tumour markers, although increased serum concentrations of carcinoembryonic antigen (CEA) are rare (17%), persistently high post-operative CEA levels were found to be a strong indicator of poor prognosis. In 55-70% of patients with CEA values of 5-10 ng·mL , an early recurrence will develop [9].Of the many analysed clinical and pathological prognostic factors, vascular invasion, lymphatic vessel and visceral pleural invasion have been identified as clearly unfavourable in terms of surviv...