Type of lymph node involvement influences survival rates in T1N1M0 non-small cell lung carcinoma. Lymph node involvement by direct extension compared with lobar and hilar node metastases.

Stage II non-small cell lung cancer represents a group of patients with varying 5-year survival rates. Of 2,009 patients, we reviewed 58 patients with pT1N1M0 disease operated on from 1977 through 1994. The N1 status was refined into lymph node involvement by direct extension and/or involvement by metastases (lobar or hilar). The cumulative 5-year survival of all hospital survivors (n = 57) was 45.7%. The 5-year survival of patients with N1 direct extension was superior to survival of patients with N1 metastases (68.6% vs 31.2%; p = 0.0038). Survival of patients with N1 direct extension was better then survival of patients with N1 hilar metastases (p = 0.0006), but did not differ from survival of patients with lobar metastases. Survival was not related to histologic features, sex, and type of resection. Recurrence of malignancy occurred less in patients with N1 direct extension. In patients with N1 hilar nodes, the most common pattern was distant metastases. Survival differs according to the type of lymph node involvement: "direct extension" seems to be an early stage of the disease, while lymph node metastases represent a more advanced form.