Mediastinal lymphadenectomy in non-small cell lung cancer: effectiveness in patients with or without nodal micrometastases - results of a preliminary study.

Objectives: So far it has not clearly been demonstrated that systematic mediastinal lymphadenectomy improves survival in patients with non-small cell lung cancer. One explanation might be that in some patients an early spread of tumor cells has occurred which might not be curable by surgical means. To test this hypothesis lymph nodes of patients which were treated either by lymph node sampling or systematic lymphadenectomy were screened for micrometastatic spread of tumor cells and the influence of nodal micrometastases on the efficacy of lymphadenectomy was analyzed.

Mode of spread in the early phase of lymphatic metastasis in non-small-cell lung cancer: significance of nodal micrometastasis.

The impact of lymphatic micrometastases on prognosis of non-small-cell lung cancer has not been clearly established. We therefore prospectively assessed the frequency, mode of mediastinal spread, and prognostic significance of lymphatic micrometastases in lymph nodes of 93 patients with completely resected non-small-cell lung cancer staged as pT1 to pT4 pN0 and pN1 by conventional histopathologic techniques. Frozen tissue sections from 471 lymph nodes that were staged as free of metastases by routine histopathologic examination were screened for micrometastases by the alkaline phosphatase-antialkaline phosphatase immunostaining technique with the monoclonal antibody Ber-Ep-4.