Methods: The records of 60 patients (57 males, 3 females; mean age 57±10 years; range 34 to 81 years) who were operated between January 2007 and October 2009 diagnosed with NSCLC in our clinic were retrospectively analyzed. Both clinical (pre-thoracotomy) and pathological (post-thoracotomy) staging were performed separately according to the sixth and seventh editions of the TNM systems.

Results: With the sixth edition, the concordance rate for the clinical and pathological T stage was 73.3% while the concordance rate for the clinical TNM and pathological TNM stage was 48.3%. Twenty percent of the patients were clinically underestimated, and 31.7% were overestimated. The seventh edition of the TNM staging yielded concordance rates of 61.7% for the clinical and pathological T stage and 41.7% for the clinical TNM and pathological TNM stage was 41.7%. With this edition, 28.3% of the patients were clinically underestimated, and 30% were overestimated. Clinical and pathological TNM staging according to seventh edition were similar to the previous stages in 81.7% and 70% of the patients, respectively while understaging was seen in 6.7% and 5.0%, respectively. Overstaging occurred in 11.7% and 25.0% of the patients, respectively.

Conclusion: In our study, the concordance rate for the clinical TNM and pathological TNM stage was lower for the seventh edition of the staging systems than for the sixth editon. This result suggests the importance of invasive staging and systematic lymph node dissection. Based on our samples with early stage, we believe that there should be no change in the treatment for patients with upstaging according to the seventh edition of the staging system.