Purpose: A surgical resection is a potentially curative treatment for non-small cell lung cancer (NSCLC). This study investigated the time trends of the surgical outcome in patients with NSCLC.
Methods: This study clinicopathologically evaluated 1487 patients who had undergone a resection for NSCLC between 1979 and 2008 during the five periods of 1979-1988, 1989-1993, 1994-1998, 1999-2003, and 2004-2008.
Results: The number of patients who underwent a resection during the five respective periods increased: 167, 261, 248, 382, and 429. The percentage of pathologic stage IA lung cancers was 16.2, 21.5, 23.0, 38.5, and 52.0% in each period, respectively, and it has risen rapidly in recent years. The percentage of adenocarcinoma has also progressively increased during each period: 49.1, 52.1, 54.7, 62.8, and 69.7%, respectively. The diameter of the tumors resected during each period was 36, 37, 38, 33, and 26 mm, respectively, showing that the tumor tended to be diagnosed at an increasingly smaller size. The postoperative 5-year survival rates during the five periods improved markedly: 34.1, 44.0, 44.9, 65.4, and 76.5%, respectively. Patients with pathologic stage IA lung cancer also exhibited increasingly higher 5-year survival rates during the five periods: 70.0, 71.2, 80.4, 89.2, and 88.7%, respectively.
Conclusion: The prognosis of NSCLC patients has remarkably improved in recent years. The increase in the number of patients with adenocarcinoma in the early stage is thought to have strongly contributed to the favorable results. Thus, early diagnosis remains a key factor for improving the survival of lung cancer patients after surgical treatment.