Numerous investigators have been trying to establish a standard terminology that would accurately describe the extent of a cancer. In 1979 lung cancer staging was formulated by the Task Force on Lung Cancer of the American Joint Committee for Cancer Staging and End-Results Reporting (AJCF). The AJC staging system employs the T-N-M nomenclature .
In this system, the letter T represents the primary tumor N regional node involvement, M distant metastases. In 1986 modifications were made to this staging system and a new international staging system for lung cancer was established.