An update on lung cancer staging.

The staging committee of the International Association for the Study of Lung Cancer has recently published, in collaboration with the International Union Against Cancer and the American Joint Committee on Cancer, the recommendations for the upcoming 7th edition of the tumor, node, metastasis classification and staging manual. This article reviews the changes in criteria for the tumor, node, metastasis components and discusses the issues that will be faced by pathologists when examining lung cancer specimens, including recommendations for tumor measurement, differentiation of multiple primary tumors versus metastases, and visceral pleural invasion.