Lung Cancer Staging—Current Status and Controversies

Lung cancer is the leading cause of cancer-related mortality in the US. Over 215,000 cases are expected to be diagnosed in 2008, with over 161,000 deaths per year. Appropriate therapy is dependent on accurate staging to determine those amenable to surgery and define the appropriate role for chemotherapy and radiation therapy. For many years, the tumor, node, metastases (TNM) classification system has stood as the means for determining treatment and assessing prognosis. Over time, however, it has become clear that certain sites of disease may not be optimally categorized using this system, leading to a proposal by the International Association for the Study of Lung Cancer (IASLC) to revise the current TNM staging criteria. In this article, the current TNM staging is reviewed, along with the controversies in staging that have led to the new recommendations.