Lymphatic spread in resectable lung cancer: can we trust in a sentinel lymph node?

The aim of this study was to describe lymphatic spread in resected lung cancer patients and evaluate for the presence for a reliable sentinel lymph node. Onethousand and eighty-eight patients with NSCLC underwent resection. Twelve to sixteen percent of the patients with primaries in the upper lobes had an involvement in the upper mediastinum; in 12 %, it was subcarinal, in 6 % and 3 %, in the lower mediastinum at paraoesophageal and ligamentum pulmonale sites, respectively. The rate of "lymph node skipping" is between 31 and 74 %. An isolated involvement of mediastinal nodes is possible without involvement of the N-1 position. Irrespective of the location of the primary tumour, there is a high incidence of "lymph node skipping" because of the specific architecture of the pulmonary, hilar and medistinal lymph nodes. Therefore, a reliable sentinel lymph node in lung cancer cannot be defined. In conclusion, systematic lymph node dissection in anatomical compartments is the gold standard for evaluation of the exact pN stage. Furthermore, a complete R/O-resection is a prognostically relevant factor in the surgery of NSCLC.