Abstract
The clinical usefulness of lymph node dissection was assessed prospectively in 477 of 596 consecutive lung cancer patients. One hundred fifty two patients with N2 non small cell disease were classified into the following three groups : 1) 29 with False negative N2 disease, which could not be detected macroscopically at the time of dissection, 2) 52 with true-positive N2 disease, and 3) 72 with obvious N2 disease. The 81 patients in groups 1) and 2) represented 17 % of the 477 eligible patients. They were compared with 325 patients with N0 and Ni disease, 68% in whom the efforts only resulted in staging. Of these 81 patients, 63 had Ti, 2 or 3 M0 disease ; 28% of them survived for 5 years or longer. Skip metastasis, defined as metastasis to the upper mediastinum without involvement of the carinal, hilar, or intrapulmonary nodes, was found in 28 patients, or 18% of the 152 with N2 disease. A part from one patient with a large bronchioloalveolar carcinoma, none of them had lower lobe disease. Of 152 N2 patients, only 11 of the 58 (19%) undergoing upper lobectomy had positive carinal nodes, while 53 patients of 94 remainders (56%) of those undergoing other operations had positive carinal nodes. Ten of 11 other patients had N2 nodes in the upper mediastinum, and one had an Ni hilar node and chest wall invasion. This means that carinal node involvement can easily be predicted before the dissection of carinal node.
We conclude that upper mediastinal dissection is not required for lower lobe tumors with negative intrapulmonary, hilar and carinal nodes, especially squamous cell carcinoma, but is required for upper lobe tumors. In upper lobe tumor, carinal node dissection can be omitted when the nodes in both the upper mediastinum and the upper lobe are intact.
