Characteristics of non-small cell lung cancer 3 cm or less in diameter.

We retrospectively investigated 308 cases of non-small cell lung cancer of < or = 3 cm diameter. There were 204 adenocarcinomas, 78 squamous cell carcinomas, 15 large cell carcinomas, and 11 other carcinomas. According to TNM staging, there were one case stage 0, 208 stage I, 22 stage II, 49 stage IIIA, 15 stage IIIB, and 13 cases stage IV. T1 disease was seen in 262 cases, T2 in 19, T3 in 10, T4 in 16, and Tis in 1. N0 disease was seen in 217 cases, N1 in 30, N2 in 60, and N3 in 1. The 5-year survival rate of all cases was 63%. There were statistically significant differences among T status (T1 vs. T3, T4), N status (N0 vs. N1, N2), and M status (M0 vs. M1) (P < 0.01). The 5-year survival rates of cases with adenocarcinoma and squamous cell carcinoma were 60% and 64%, respectively. In 204 cases of adenocarcinoma, T3 disease was found in one case, T4 disease in 15 (7%), and nodal involvement (N1 + N2) was present in 69 (34%). In 78 cases of squamous cell carcinoma T3 was seen in 6 (8%), T4 in 1, and nodal involvement in 14 (18%). The incidence of T3 disease, T4, and N(+) varied significantly according to histology (P < 0.05). Our investigation suggested that cases of small-sized lung cancer were often at an advanced stage at detection, and that the spread of disease differed according to histology. The patient with small-sized lung cancer should be offered a standard operation regardless of histology.