Cancer staging helps to understand the location of cancer, tendency to spread and affect other organs of the body. A series of diagnostic tests are conducted to help doctors to understand the cancer stage. Cancer staging is important to detect for the following reasons:
To make a treatment plan. Depending upon the staging doctor can decide whether surgery, chemotherapy, radiotherapy, or combination treatment require.
Prediction cancer recurrence probability after completion of the treatment.
Prediction of recovery chances
Helps to discuss the patient’s condition with other healthcare teams.
Determine the treatment effectivity
Determine to advise a patient to join a clinical trial to obtain new treatment if the patient’s condition cannot be treated with the available treatment procedure.
The American Joint Committee on Cancer describes cancer staging as a TNM system. Doctors do TNM staging by monitoring diagnostic results, imaging scan reports, by removing part of the tumor as a sample, following are the determining points of the TNM system:
Size and location of the primary tumor [Tumor (T)]
The tendency to spread tumor in the lymph node. If the result is positive, then the location and number of lymph nodes are affected. [Node (N)]
Cancer spreading tendency to other parts of the body. If the result is positive, then the location and extent of spreading of the cancer are required to measure. [Metastasis (M)].
The presence of biomarkers or tumor markers links to cancer influences cancer spreading.
Cancer staging can also be conducted after giving radiotherapy, chemotherapy, or immunotherapy, but before surgery. This post-therapy cancer staging (y) helps to determine the shrinkage of cancer and also helps to predict how surgical intervention helps to remove the remaining part of cancer.
A tumor (T): The size, location, and also how extent a tumor spreads to adjoined tissues are described by the letter T along with the number (0 to 4). The size of the tumor is measured in centimeters. A large-sized tumor can more invasively spread to the adjoined tissues. In some cases, T staging is added additional lower case letters a, b, m (multiple) to describe more details about T staging cancer.
Node (N): The N staging cancer along with a number (0 to 3) describes lymph node. Lymph nodes are tiny bean-shaped organs that take part in infection prevention. The lymph node where cancer begins is denoted as a regional lymph node. The other parts of the lymph node known as a distant lymph node. More number of the lymph node with cancer is denoted with a higher number. Some tumors in lymph nodes with cancerous growth are categorized under ‘N’.
Metastasis (M): The cancers spread to other parts of the body which are categorized under distant metastasis are denoted with the letter “M”. In case of cancer not spread to other parts of the body is categorized as M0, and if cancer has spread to other parts is termed as M1.
Cancer stage grouping
Oncologists grouping the cancer stage in combination with TNM categories along with other factors like grade, tumor markers, and tumor genetics. Mostly cancer stage has four groups, which are denoted as stages I (1) to IV (4). However, some cancers are grouped under stage 0 (zero).
Stage 0. If cancer remains in the place from where it is generated and does not spread to other distant organ is grouped under stage 0. In one word stage 0 means “in place”. Stage 0 cancer is usually curable through surgical intervention helps to remove the entire tumor.
Stage I. This indicates the early stage of cancer. The size of the cancerous tumor is small and does not spread to adjoining tissue, nor affect lymph nodes or other organs.
Stage II and Stage III. Generally, larger sized cancers are categorized under these two different stages. These cancerous tumors are deeply invading the affected tissue and often affect nearby tissues. They may spread to lymph nodes but not affect other organs of the body.
Stage IV. This stage indicates advanced, metastatic cancers, which spread to other organs or parts of the body.