[Skip metastasis to the mediastinal lymph nodes in non-small cell lung cancer].

OBJECTIVE

To ascertain if any difference exists in clinical characteristics between resected non-small cell lung cancer (NSCLC) with either skip or ordinary mediastinal lymph node metastases.

METHODS

Among 176 patients with stage IIIAN2 disease between 1982-1994 treated in our hospital, 53 had no metastasis at the hilar lymph nodes [skip(+) group] while 123 had [skip(-) group]. To investigate the extent of nodal involvement, the mediastinal lymph nodes were divided into three regions.

RESULTS

In the skip(+) group, mediastinal node metastasis was found in only one region in 49 of the 53 patients(92.4%), whereas 45 of the 123 patients(36.6%) from the skip (-) group revealed medinastinal metastasis at two or three regions The overall survival rate at 5 years after operation was 29.3% in the skip(+) group and 12.2% in the skip (-) group (P = 0.038). Furthermore, regarding patients with mediactint node metantion in one region, the skip(+) group had a better prognosis than the skip (-) group (32.1% vs 15.3%, P = 0.042).

CONCLUSION

These results suggest that patients with skip mediastinal lymph node metastases represent a unique subgroup of N2 disease.