TNM: Our Language of Cancer
Authors: F. L. Greene
Journal: CA A Cancer Journal for Clinicians (2004)

For more than four decades, the American Joint Committee on Cancer (AJCC) has played a leadership role in the United States as the collective organization that provides oversight of cancer staging for most solid tumors seen in clinical practice. From the inception of this coordinated effort, the American Cancer Society (ACS) has played a vital role in the development and the ongoing activities of the AJCC. As a founding member, the ACS has worked with the AJCC to ensure that the tumor-node-metastasis (TNM) system as a prognostic factor in cancer is perpetuated and improved through rigorous scientific evaluation. It is quite appropriate, therefore, that a series of articles dedicated to TNM staging appear in CA, a scientific publication of the ACS. This series of articles is designed to review the changes that have been made to the TNM staging system, which have appeared in the sixth edition of the AJCC Cancer Staging Manual.1 The review published in this edition of CA is the first in this series and is dedicated to the staging issues relative to the management of melanoma. Over the next 18 to 24 months, additional publications will appear that are directed to the staging strategies and management of other major cancers, and they will be authored by experts who lead our AJCC Task Forces in their respective oncologic areas. It is imperative that all of us who care for the cancer patient embrace a common language that allows us to give appropriate prognoses to our patients and enhances the dialogue among personnel in specialties caring for patients with neoplastic disease. It is especially important that we emphasize adequate staging in the future as we develop new clinical trials to assess multimodality treatment, including the molecular management of cancer. The AJCC, along with the International Union Against Cancer/Union Internationale Contre le Cancer (UICC), is committed to carrying on the tradition of TNM that was developed by Pierre Denoix, a surgeon, while working in France in the 1940s and 1950s. In the mid-1980s, a unique worldwide agreement2 was forged to assure that TNM staging of cancer would become the common language for cancer staging and would be utilized by clinicians throughout the world. Although this goal has yet to be reached, the AJCC and UICC are committed to continuing this effort.3 This series of articles will also highlight the introduction of newer and more specific methods of diagnosis and elucidation of even the minutest cellular characteristics of cancer. While changes in the TNM staging taxonomy do not affect all tumors, there are important newly identified global issues that do have a bearing on all cancers. These include molecular identification of metastases and the continued effort by pathologists to uncover smaller and smaller cell clusters that may ultimately have a bearing on the multimodality management of our patients. These issues will be discussed, and the concepts will be outlined for future evolution of this important topic. Similarly, diagnostic strategies such as positron emission tomography scans are extending the envelope in diagnosis and staging of many tumors such as colorectal cancer, melanoma, lymphoma, and lung cancer. The importance of these newer imaging studies and their effect on the clinical TNM stage will be emphasized in our ongoing series. The roles of both the AJCC and the ACS go well beyond creation and maintenance of a common language for cancer care. Our organizations are also dedicated to the education and promotion of a dialogue using TNM that includes physicians, nurses, and all members of the health care team who care for patients with cancer. An additional important benefactor of the system in the United States is our cancer registrar community. Registrars work diligently at many hospitals as well as state and national registries to ensure that clinical and pathologic information are recorded properly and that this information is maintained in a consistent format to be used for patient care, clinical research, and the accumulation of important epidemiologic data. Certified tumor registrars are on the front line to adapt to any changes in our cancer vernacular. The AJCC, ACS, and ultimately the cancer patients are the direct benefactors of their outstanding contributions. As Chair of the AJCC, I want to emphasize the great debt that we owe to the ACS in supporting and maximizing the efforts of appropriate staging for our cancer patients. It is quite appropriate, therefore, that CA, as a vehicle for the ACS, takes a prominent role in the education and promotion of TNM for all those who care for cancer patients in this country and around the world.