What Are The Stages of Stomach Cancer? – (TNM Staging) – Part 1
There are two different stages that distinguish stomach cancer: the clinical stage and the pathologic stage. Both stages play an important part in the assessment and prognosis of a patient.
The Clinical Stage – This is the first stage where the use of physical exams, endoscopy, CT scans, and biopsies are used to help create a suitable treatment plan for the patient. However, sometimes the patients metastasis (cancer spread) has gone further than was first estimated. It is here that the pathologic stage comes into play (after surgery has been carried out).
The Pathologic Stage – This is the second stage, and uses the same test results as the clinical stage, plus what was found from tissues that were removed during surgery. Once the pathologic stage has been carried out, the staging of the stomach cancer can be determined.
The staging system used for stomach cancer is the TNM system which contains three important pieces of information.
1. T – The extent of the primary tumor (original tumor) and how far it has extended into the stomach wall and nearby organs.
2. N – The metastasis to regional (nearby) lymph nodes.
– (NX) The regional lymph nodes cannot be assessed.
– (N0) No cancer has metastasized to the regional lymph nodes.
– (N1) The cancer has metastasized to 1 – 2 regional lymph nodes.
– (N2) The cancer has metastasized to 3 – 6 regional lymph nodes.
– (N3) The cancer has metastasized to 7 regional lymph nodes.
– (N3a) The cancer has metastasized to 7 – 15 regional lymph nodes.
– (N3b) The cancer has metastasized to 16 or more regional lymph nodes.
3. M – Whether the cancer has metastasized to other parts of the body. The most common parts for this metastasis to have taken place are: the liver, the peritoneum (lining of the space around the digestive organs), and the distant lymph nodes.
– (M0) There has been no distant metastasis to organs such as: the liver, the lungs, or the brain.
– (M1) There has been distant metastasis to other organs or the lymph nodes
Once the T, N, and M categories have been determined, these are combined with other letters and numbers.
1. 0 to 4 – Increasing severity of the cancer.
2. X – Cannot be assessed due to the lack of sufficient information.
3. is – (Carcinoma in situ) The tumor is in the top layer of the mucosa cells, and has not yet invaded the deeper tissue layers.
This system is used for most types of stomach cancer, apart from where the cancer originated in either the gastroesophageal junction (the stomach and esophagus meeting point), or the cardia (the first part of the stomach) and growing into the gastroesophageal junction.
TNM System Grouping
Once the T, N, and M categories have been determined, this information is combined and expressed as a stage or staging, using the number 0 (zero) and Roman numerals I through to IV. This is known as stage grouping. Some stages are split into sub-stages indicated by letters.
A more detailed explication of how the TNM Staging System works can be found in: “What Are The Stages of Stomach Cancer? – (TNM Staging) – Part 2”
Philip was born in the United Kingdom. Today he works as a freelance writer in Mexico, where he spends much of his time researching and writing about health related issues. If you feel that you have benefited from reading one of his articles: please recommend them to others who may also benefit. Thank you for reading Philip’s articles!