Mediastinal lymph node infiltration in non-small cell lung cancer and its role in curative surgery.

Despite the importance of lymph node infiltration for the classification and prognosis of non-small cell lung cancer (NSCLC), there are no accepted standards for quality of mediastinal lymphadenectomy. In 270 consecutive patients undergoing potentially curative surgery for NSCLC, including complete ipsilateral lymph node dissection, we investigated the possibility of a correlation between tumour location and lymph node infiltration. The tumours were classified as UICC stage I (n = 115), II (n = 42) or IIIa (n = 113). Patients with N2-disease (n = 68) showed up to 81% skip metastasis. Because of the observed dissemination of lymph node metastasis, tumour location could not predict nodal infiltration. The variability of nodal involvement and the frequent occurrence of skip metastasis thus make complete ipsilateral lymphadenectomy mandatory for curative management of NSCLC.