On the new (version 9) American Joint Committee on Cancer tumor, node, metastasis staging for cervical cancer—A commentary

Despite a remarkable decline in cervical cancer rates in the 20th century, cervical cancer remains the fourth leading cause of cancer deaths for women globally. Although countries with wellestablished cervical cancer screening programs have a significantly lower burden of disease, the number of new cases, including cases in the United States, is not to be underestimated. Recently, the American Joint Committee on Cancer (AJCC), in conjunction with the International Union Against Cancer, released an update of AJCC’s TNM staging for cervical cancer (version 9). Not only does the new version allow for better alignment with the International Federation of Obstetrics and Gynecology (FIGO) system, but there are also several important changes from the prior version, which have been outlined by Olawaiye et al in CA: A Cancer Journal for Clinicians and which serves as the basis for this concise commentary. The major changes to the new staging system include the incorporation of all modalities of imaging as well as pathology in the staging of these tumors and the introduction of changes involving size criteria and the most recent World Health Organization (WHO) histologic classification into the AJCC staging system. These changes allow for the integration of these modalities to better stage cervical cancer and will lead to better management planning. Prior editions from the AJCC included only the use of physical examination findings and plain radiographs despite significant advances in the use of various imaging modalities (eg, computerized tomography, magnetic resonance imaging, and positron emission tomography) for the evaluation of women with gynecologic cancers. Additionally and also importantly, pathology findings are now incorporated because they often can provide a more accurate assessment of some parameters, including measurement of tumor size from hysterectomy specimens rather than that obtained from clinical examination or imaging. Other specific changes to the TNM categories have also been made. For the T (tumor) category, T1a is now determined only on the basis of the depth of invasion and not on the basis of the extent of horizontal spread because horizontal spread is considered to be a less accurate measurement. In view of the relation of tumor size to prognosis, the T1b category has been divided into 3 subcategories based on the maximum diameter size (T1b1, ≤2 cm; T1b2, >2 cm to ≤4 cm; T1b3, >4 cm). 7 There were no updates to the T2, T3, and T4 categories beyond those stated previously for the incorporation of imaging and pathologic/surgical findings. For the N (node) category, version 9 of AJCC staging now incorporates the lymph node status as determined by either radiologic or surgical findings. Pelvic lymph node involvement is designated N1, whereas paraaortic lymph node involvement, which is associated with a worse prognosis, is designated N2. When a pathologic evaluation is possible, the categories are based on the size of the metastasis and include isolated tumor cells (ITCs) (<0.2 mm), micrometastasis (0.22 mm), and macrometastasis (>2 mm). Similarly to