
Anal Cancer Symptoms, Screening and Diagnosis
Staging
The stage of a cancer tells you its size and whether it has spread. It helps determine how serious the cancer is and which treatments are best.
The method your clinician is most likely to use to determine the stage of your colorectal cancer is the TNM staging system. The TNM staging system stands for tumour, node and metastases (Greene & Sobin, 2008, p. 180).
- T describes the size of the tumour (cancer)
- N describes whether there are any cancer cells in the lymph nodes. Lymph nodes are small, bean-shaped collections of immune cells. Many types of cancer often spread to nearby lymph nodes before they reach other parts of the body.
- M describes whether the cancer has spread to a different part of the body
T staging | |
TX | Primary tumour could not be evaluated |
T0 | No evidence of primary tumour |
Tis | High-grade squamous intraepithelial lesion, carcinoma in-situ |
T1 | Tumour < 2 cm |
T2 | Tumour 2-5 cm |
T3 | Tumour > 5 cm |
T4 | Tumour of any size with adjacent organ invasion |
N staging | |
NX | Regional lymph node could not be evaluated |
N0 | No metastatic lymph nodes |
N1 | Inguinal, Mesorectal, Internal iliac, or external iliac nodes |
N1a | Inguinal, Mesorectal, or Internal iliac lymph nodes |
N1b | External iliac lymph nodes |
N1c | External iliac lymph nodes with N1a |
M staging | |
M0 | No distant metastasis |
M1 | Distant metastasis |
Cancer stages by size and growth
Healthcare providers use a number system to stage most cancers. The stages of cancer are:
STAGE | LOCATION |
STAGE 0 | The cancer has not grown beyond the first layer of the colorectal wall; it is non-invasive cancer. |
STAGE I | The cancer has grown into either the second or third layer of the colorectal wall, but there is no cancer in nearby or distant sites. |
STAGE II | The cancer has grown into the fourth layer of or the outside of the colorectal wall; there is no cancer nearby or distant sites. |
STAGE III | The cancer has spread from the colorectal to nearby lymph nodes or there are small secondary tumours within the colorectal. |
STAGE IV | The cancer has spread to distant organs such as the liver or lungs. |
Literature
1. Greene, F. L., & Sobin, L. H. (2008). The staging of cancer: A retrospective and prospective appraisal. CA: A Cancer Journal for Clinicians, 58(3), 180–190. https://doi.org/10.3322/CA.2008.0001