Survival of Cases of Resected Primary Lung Cancer

We analyzed 547 resected cases of primary lung cancer treated at 8 major Japanese institutions from 1975 to 1976 inclusive. The male to female ratio was 3: 1. Each patient was assigned a postsurgical pathologic stage classification on examination of the resected specimen. There were 219 cases classified as stage I, 52 as stage II, 240 as stage III, and 36 as stage IV. The cell types were as follows: squamous cell carcinoma 225 (41.1%); adenocarcinoma 231 (42.2%), small cell carcinoma 34 (6.2%); large cell carcinoma 33 (6%); adenosquamous cell carcinoma 10 (1.8%); and others 14. The cumulative proportion of patients surviving 5 years following resection shows statistically different survival patterns according to the postsurgical stage of disease. Sixty one % of patients with stage I disease, 27% of those with stage II disease, and 10.5% of those with stage III disease survived 5 years respectively. The best overall survival was achieved in cases of squamous cell carcinoma, a cumulative 41.7% surviving 5 years. The outcome of cases of adenocarcinoma was statistically worse than for patients with squamous cell carcinoma, 24% surviving 5 years. However the outcome for adenocarcinoma patients was statistically better than for undifferentiated carcinoma groups. The effect of lymph node involvement on the prognosis of resected cases was very poor. The 49.8% 5-year survival of resected cases with no lymph node involvement decreases to 27.1% if hilar nodes are involved and drops further to 5.3% if mediastinal lymph nodes are involved. Observing the relationship of type of surgery to survival, patients with curative resections had significantly better 5-year survival (57.1%), patients with relatively curative resections had a 26.8% 5-year survival rate, and in patients who had undergone non-curative resections the 5-year survival rate significantly dropped to 10.7%.