The metastatic patterns of nodal involvement in lymph node stations No.12 and No.13 in non-small cell lung cancer and their clinical significance

Objective: To investigate the metastatic patterns of nodal involvement in lymph node stations No. 12 and No. 13 in non-small cell lung cancer and their clinical significance. Methods: The clinicopathological characteristics of 141 patients undergoing pneumonectomy or lobectomy and lymphadenectomy for non-small cell lung cancer were analyzed. Results: The total number of resected lymph nodes was 2 154, and the mean number of dissected lymph nodes was 15.3 in each patient. The positive rate of lymph node involvement was 13.1%. Fifty-five patients were confirmed as having thoracic lymph node metastases out of 141 patients. The numbers of patients with nodal metastases of N 1 , N 2 and skip-N 2 were 15, 28 and 12, respectively. The metastatic rate was 39.0%. Seven patients with nodal involvement in lymph node stations No.12 or No.13 were identified from 93 patients without mediastinal and intrapulmonary lymph node metastases confirmed by routine pathological examination. The detection rate was 7.5%. The metastatic rate of lymph node stations No.12 and No.13 in patients with stage T 2 was obviously higher than that in patients with stage T 1 (P 0.05), and the metastatic rates of lymph node stations No.12 and No.13 in poorly and moderately differentiated lung cancer were 25.0% and 8.9%, respectively (P 0.05). The metastatic rate of lymph node stations No.12 and No.13 was much higher in peripheral lung cancer than in central lung cancer (P 0.05). Conclusion: The metastases of lymph node stations No.12 and No.13 were closely correlated with the size, pathological type and differentiation of primary tumor. The pathological examination of lymph node stations No.12 and No.13 in early-stage non-small cell lung cancer may provide a valuable guidance in clinical practice. [