Source:http://linkedlifedata.com/resource/umls/id/C1142025
NCI: Stage IV includes: Any T, Any N, M1, Any G, Tumor location: Any. M1: Distant metastasis. Tumor location: Location of the primary cancer site is defined by the position of the upper (proximal) edge of the tumor in the esophagus. (AJCC 7th ed.)