Prognostic value of T and N in non small cell lung cancer three centimeters or less in diameter

OBJECTIVE: Peripheral tumors 3 cm or less in diameter are classified T1,T2 when rupturing the visceral pleura, T3 when invading parietal pleura,chest wall, mediastinal pleura or pericardium and T4 when invading vertebraor mediastinal structures. Our objective was to assess the prognosticsignificance of T and N status according to the size of such tumors.PATIENTS AND METHODS: Patients (918) were operated upon between April 1984and December 1991. Surgery included complete resection and mediastinallymphadenectomy. Tumors 3 cm or less were studied concerning T, N status,histology and survival. RESULTS: There were 314 such tumors (T1 = 215, T2 =64, T3 = 35, T4 = 6); N status was N0 60.2%, N1 21%, N2 18.8%. Global5-year survival was 52.59%. In case of N0, survival was 64.63%: T1 =63.76%, T2 = 71.48%, T3 = 45.71%, T4 = 66.6%; which was not significant.There were 48 tumors 1.0 cm or less in diameter (G1), 111 tumors 1.1-2.0 cmin diameter (G2) and 155 tumors 2.1-3 cm in diameter (G3). The incidence ofN0, N1 and N2 disease was 77.1, 10.4 and 12.5%, respectively in G1, 64, 18and 18% in G2, and 52.3, 26.5 and 21.3% in G3. The 5-year survival rate was62.46% for G1, 52.91% for G2 and 49.36% for G3 (NS). In cases of N1 and N2,survival was 48.41% and 20.2% which was significant (P < 0.05) butdifferences between each T and each G were not significant. CONCLUSIONS:Small peripheral cancers spread into mediastinal nodes in 12.5-21.3% ofcases, according to the size. This is a warning to perform nodes resectionsin cases where surgeons intend a videothoracoscopic approach. N2 status isnot only an indicator but also a governor of prognosis. Neither T statusnor size are determinants of prognosis as far as tumors 3 cm in diameter orless are concerned.