Non-Small-Cell Lung Cancer (NSCLC) is the most common malicious neoplasm characterized by very bad prognosis: 5-year survival rate is only 15%, and the main factors responsible for unfavorable treatment results are late diagnosis, rapid progression of the tumor and high rate of metastasis. The most important issue before selection of the treatment is to establish presence of the metastasis to nodes on the same side of the body (N2) and to lymph nodes on the other side of the mediastinum or a spread to the supraclavicular nodes (N3).