Chronological changes in lung cancer surgery in a single Japanese institution

Abstract

Background: The aim of this study was to evaluate the chronological changes in epidemiological factors and surgical outcomes in patients with lung cancer who underwent surgery in a single Japanese institution.

Patients and methods: A clinicopathological database of patients with lung cancer who underwent surgery with curative intent from January 1974 to December 2014 was reviewed. The chronological changes in various factors, including patient's age, sex, histological type, tumor size, pathological stage (p-stage), surgical method, operative time, intraoperative blood loss, 30-day mortality, and postoperative overall survival (OS), were evaluated.

Results: A total of 1,616 patients were included. The numbers of resected patients, females, adenocarcinomas, p-stage IA patients, and age at the time of surgery increased with time, but tumor size decreased (all P<0.0001). Concerning surgical methods, the number of sublobar resections increased, but that of pneumonectomies decreased (P<0.0001). The mean operative time, intraoperative blood loss, and the postoperative 30-day mortality rate decreased (all P<0.0001). When the patients were divided into two groups (1974-2004 and 2005-2014), the 5-year OS rates for all patients and for p-stage IA patients improved from 44% to 79% and from 73% to 89%, respectively (all P<0.0001). The best 5-year OS rate was obtained for sublobar resection (73%), followed by lobectomy (60%), combined resection (22%), and pneumonectomy (21%; P<0.0001).

Conclusion: Changes in epidemiological factors, a trend toward less invasive surgery, and a remarkably improved postoperative OS were confirmed, which demonstrated the increasingly important role of surgery in therapeutic strategies for lung cancer.

Keywords: 30-day mortality; less invasive surgery; lung cancer; sublobar resection; surgery.

Figure 1

OS curves of all patients who underwent resection for lung cancer show a significant survival difference between patients from 1974 to 2004 (n=868) and those from 2005 to 2014 (n=748; log-rank test, P<0.0001). Abbreviation: OS, overall survival.

Figure 2

OS curves of p-stage IA patients who underwent resection for lung cancer show a significant survival difference between patients from 1974 to 2004 (n=239) and those from 2005 to 2014 (n=318; log-rank test, P<0.0001). Abbreviations: OS, overall survival; p-stage, pathological stage.

Figure 3

OS curves of patients are significantly different among four surgical methods including sublobar resection (wedge resection or segmentectomy), lobectomy (including bilobectomy), pneumonectomy, and combined resection with adjacent organs (log-rank test, P<0.0001). Abbreviation: OS, overall survival.