CRC staging and TNM classification CRC staging and

CRC: staging and TNM classification

CRC staging and TNM classification • The most frequently used system to stage CRC is the American Joint Committee on Cancer TNM system, which is based on: 1 – The size and extent of the primary tumour (T) – Whether the cancer has spread to nearby (regional) lymph nodes (N) – Whether the cancer has metastasised to other organs (M) • Once the T, N and M categories have been defined, this information is combined to assign an overall stage of 0, I, III or IV 1 • This process is called stage grouping, and results in a range of anatomical stage or prognostic groups (right) • The Dukes system has been used historically to stage CRC 2 CRC, colorectal cancer; T 1 mi, minimally invasive adenocarcinoma; Tis, tumour in situ; TNM, tumour, node, metastasis. 1. Gress DM, et al (Eds). Principles of cancer staging. AJCC Cancer Staging Manual. 8 th ed. New York, NY: Springer. 2017. 2. Haq AI, et al. Lancet Oncol 2009; 10: 1128. Anatomic stage/prognostic groups

CRC TNM classification explained 1 *There is no designation of MX. The absence of any clinical history or physical findings suggestive of metastases in a patient who has not undergone any imaging is sufficient to assign the clinical M 0 category. There is no designation of p. M 0. Biopsy or other pathological information is required to assign the pathological M 1 category. Patients with a negative biopsy of a suspected metastatic site are classified as clinical M 0 (c. M 0). c. M, clinical metastasis; Tis, tumour in situ. 1. Gress DM, et al (Eds). Principles of cancer staging. AJCC Cancer Staging Manual. 8 th ed. New York, NY: Springer. 2017.

International disease classification system: CRC • ICD-O codes are a subgroup of oncology-specific codes within the overarching ICD coding architecture 1 Example ICD-O topography codes for malignant colorectal neoplasms 2, 3 • The structure of ICD-O codes indicates a tumour’s: 1 – Topography: location / site within the body: • All CRC codes are denoted by the prefix C – Morphology/histology: appearance when examined under the microscope ICD-O, International Classification of Diseases for Oncology. 1. Fritz A, et al. International Classification of Diseases for Oncology 2000; 3 rd ed. World Health Organization. Available at: https: //apps. who. int/iris/handle/10665/42344 (Accessed September 2019). 2. Colorectal Cancer Control Program. Approved ICD-10 Code List. 2019. Available at: https: //www. michigancancer. org/Colorectal/PDFs/ICD 10 Codes/FY 20 CRCICD 10. pdf (Accessed September 2019). 3. Kuipers EJ, et al. Nat Rev Dis Primers 2015; 1: 150652.