Classification
of Malignant Tumours (TNM) Cancer Staging System - Intro, Tumor
Classification & Parameters, Applications & Objectives
(July 30th, 2008)
 The
TNM (Classiciation of Malignant Tumors) Cancer staging system was
designed to gauge the extent of Cancer in a patient's body. T stands
for the size of the Tumor and if the tumor has invaded nearby tissues,
N stands for lymph nodes that may have become malignant, and M stands
for metastasis (spread of cancer from one organ of the body to another).
TNM was designed by the International Union Against Cancer (UICC)
and serves as a worldwide standard for determining the extent of
lung cancer in human body. It also works in conjunction with International
Federation of Gynecology and Obstetrics (FIGO) and American Joint
Committee on Cancer (AJCC).
Classification of Tumors
Every type of tumor has its own unique TNM classification. For
example, lung cancer, colon cancer, stomach cancer, etc all have
their own TNM classifications. Here is how a TNM classification
is coded, in scientific terms (including parameters).
Compulsory Parameters ('T', 'N', 'M')
- T (a,is,(0),1-4): Stands for size of the primary tumor.
- N (0-3): Degree of metastasis (spread) to regional lymph nodes
-> N0 = Tumor cells not present in lymph nodes
-> N1 = Tumor cells have spread to nearby lymph nodes, but haven't
metastasized far enough
-> N2 = Tumor cells have spread to distances between N1 and N3
-> N3 = Tumor cells have spread to most distant & far lymph
nodes
- M (0/1): Determines whether metastasis (spread of cancer to other
organs within the body) has occured
-> N0 = No distant metastasis
-> N1 = Metastasis has occured to nearby & faraway organs
in the body, beyond the regional lymph nodes
Other Parameters
- G (1-4): Measures 'grade' of the Cancerous cells; 'low grade'
if they appear like normal cells, 'high grade' if they appear all
different from each other
- L (0/1): Determines whether lymphatic vessels (such as lymph
nodes) are damaged
- V (0/1): Determines whether the veins are damaged
Coding
pT1 N0 M0 G1 - This coding of 'TNM' stands for Low Grade cancer
cells (pT1), no metastasis (M0), no spread to lymph nodes (N0)
pT4 N2 M1 G3 - This coding of 'TNM' stands for High Grade cancer
cells (PT4), metastasis involved, tumor cells have invaded the lymph
nodes
Usefulness of the TNM System
The TNM staging system is used for these purposes:
- Gives doctors an indication of prognosis and which treatments
to be given to the patient
- Assists in assessing results of treatment therapies
- Helps doctors & their assistants to properly plan treatment
options for their patients
- Since it is a worldwide standard, doctors from all over the globe
can use this system and share valuable information back and forth,
for the advancement of this system
|
