Microsized lung adenocarcinoma vs. small-sized lung adenocarcinoma: clinical characteristics, advantages and surgical implications

Owing to the advances in imaging techniques such as thin-section computed tomography (CT) and 3D imaging, lung cancer can now be diagnosed at an early stage. The detection of small-sized lung cancer, including the 1 cm in diameter or less, is remarkably increasing. As a consequence, in 2015 the International Association for the Study of Lung Cancer (IASLC) proposed the new TNM staging system of lung and pleural tumours, in which T1 (≤3 cm) non-small-cell lung cancer (NSCLC) tumors were divided based on tumour size into T1a (≤1 cm), T1b (>1 and ≤2 cm) and T1c (>2 and ≤3 cm) (1). In this scenario several studies have investigated the role of limited resections, such as wedge and segmentectomy, in the treatment of small size lung cancer (<2 cm). Particularly, the hypothesis zero is the assumption that, in this type of lung cancer, no significant differences in survival rate are identified when patients who underwent lobectomy and those who were subjected to a limited resection are compared.