The American Joint Committee on Cancer (AJCC) editions of the TNM classification for breast cancer, which classifies cancer by several factors, is an internationally agreed system but it has gradually evolved through its different editions (ten) which were published from 1977-2009.
In 1987, the UICC and AJCC staging systems were unified into the single TNM staging system. 
Amin, Mahul B.; Edge, Stephen B.; Greene, Frederick L.; Byrd, David R.; Brookland, Robert K.; Washington, Mary Kay; Gershenwald, Jeffrey E.; Compton, Carolyn C.; Hess, Kenneth R.; Sullivan, Daniel C.; Milburn Jessup, J.; Brierley, James D.; Gaspar, Lauri E.; Schilsky, Richard L.; Balch, Charles M.; Winchester, David P.; Asare, Elliot A.; Madera, Martin; Gress, Donna M.; Meyer, Laura R. (2016). AJCC Cancer Staging Manual (8th ed.). ISBN 978-3319406176. Delayed to go into effect 2018. 
UICC TNM Classification (8th ed.). 2016. Went into effect 2017. 
