The AJCC Cancer Staging System, including the updates for Nasopharynx, Thymus, Lung and Diffuse Pleural Mesothelioma - Version 9 Protocol content is used by physicians and health care professionals throughout the world to facilitate the uniform description and reporting of neoplastic diseases. Proper classification and staging of cancer is essential for the physician to assign proper treatment, evaluate results of management and clinical trials, and to serve as the standard for local, regional and international reporting on cancer incidence and outcome. Significantly expanded and developed by international disease site expert panels, the AJCC Cancer Staging System brings together all the currently available knowledge on staging of cancer at various anatomic sites. Evidence-based TNM staging is supplemented, as appropriate, by selected molecular markers and newly acquired insights into the molecular underpinnings of cancer. The AJCC Cancer Staging System remains the gold standard reference for oncologists, surgeons, pathologists, radiologists, cancer registrars and medical professional’s world- wide to ensure that all those caring for cancer patients are fully versed in the language of cancer staging. Version 9 of the Nasopharynx, Thymus, Lung and Diffuse Pleural Mesothelioma, Cancer Staging System becomes effective on January 1, 2025, and adds to the 8th Edition of Nasopharynx, Thymus, Lung and Malignant Pleural Mesothelioma, cancer site content.

AJCC Moved from Editions to Versions

The American Joint Committee on Cancer (AJCC) made an important change to how it updates and releases Cancer Staging content. The AJCC shifted from a Cancer Staging Manual to a Cancer Staging System and moved away from Editions to Versions. Updated Version 9 disease sites go into effect on January 1, 2025 following their release.