A Clinical Study in Small Sized Lung Cancer of Peripheral Type Less than 2cm in Diameter

Seventy-six patients with small peripheral type lung cancers underwent pulmonary resection in our hospital from 1972 to 1989. In all 76 patients, five-year survival rates were 77% for stage I, 71% for stage II, 36% for stage III, and 0% for stege N, respectively. Although tumors were less than 2cm in diameter, the course was poor in advanced cases (stage III, N). In small peripheral type lung cancers less than 2cm in diameter, pleural involvement, lymphatic invasion, vascular invasion and grade scars correlated significantly with the pathological stages. In this group, the tumor size of most advanced cases was from 1.6cm to 2cm, but in 2 patients it was less than 1.5cm in diameter. The mean age of 12 cases with advanced cancer was 53 years old and reason for detection was symptomatic in 6 cases. Histologically, 11 patients had adenocarcinoma and one had small cell carcinoma. DNA ploidy was analyzed by flow cytometry in 8 advanced cases. Four cases showed diploidy and 4 cases showed aneuploidy, but no relationship with their course was recognized. Concerning the reason for classification as stage III or IV, 5 patients were N2, 5 patients had pulmonary metastasis and 4 patients had pleural dissemination.