[The usefulness of mediastinoscopy for primary lung cancer].

The usefulness of mediastinoscopy for lung cancer was retrospectively evaluated for the aspect of prognosis. The subjects were 421 patients with primary lung cancer except exploratory thoracotomy. In the MD(+) group, there was no difference in prognosis between right and left sided thoracotomies, but in the MD(-) group there was a tendency for poorer prognosis in the left-sided thoracotomy (p < 0.1). In the right-sided thoracotomy, there was no difference of prognosis between the MD(+) group and MD(-) group. On the contrary, in the left-sided thoracotomy there was a statistically better prognosis in the MD(+) group than in the MD(-) group (p < 0.05). In the left-sided thoracotomy group, there was a statistically better prognosis in the MD +) group than in the MD(-) group in the pN 0 or pN 1 group (p < 0.01), but there was no difference of prognosis in the pN 2 group. In lung cancer of the left side, the mediastinal lymph node dissection would be more incomplete because of the presence of the aorta and the mediastinal lymph node metastasis would tend to be missed. Mediastinoscopy gives the right diagnosis of mediastinal lymph node metastasis and an accurate staging of lung cancer. Mediastinoscopy is very useful especially in the left-sided lung cancer.