Limited mediastinal lymph node dissection for non-small cell lung cancer according to intraoperative histologic examinations

Background Although radioisotopic procedures are commonly used to detect sentinel lymph nodes in breast cancer surgery, these procedures are often problematic and not necessarily suitable for lung cancer surgery. Methods Our previous study revealed that the mediastinal sentinel lymph node, defined as the regional mediastinal lymph node, consisted of nodes 2, 3, or 4 in right upper lobe cancers; 3, 7, or 8 in right lower lobe cancers; 4, 5, or 7 in left upper lobe cancers; and 4, 7, or 8 in left lower lobe cancers. On the basis of these findings, we pathologically investigated one representative lymph node at each of the 3 levels dissected during surgical intervention in 69 patients with non-small cell lung cancer from September 1993 through December 2002. Fifty-eight patients with lung cancer underwent lobectomies with limited mediastinal lymph node dissection according to this strategy. Results Mediastinal lymph node recurrence was observed in only one patient during 41 ± 25 months (maximum, 98 months) of follow-up. The cancer-specific 5-year survivals were 96.6% in patients with pathologic stage IA disease (n = 31) and 67.4% in patients with stage IB disease (n = 16). Conclusion These results suggested that limited mediastinal lymph node dissection is applicable to patients with non-small cell lung cancer whose regional mediastinal lymph nodes are not metastatic.