Overview of Cancer
The word "cancer" refers to a broad category of illnesses that arise when the body's abnormal tissue cells proliferate out of control and spread to other parts of the body. It is typified by unchecked cell division and can impact nearly every area of the body. Genetic mutations, environmental variables (like smoking, pollution, or radiation), and lifestyle factors (like food or physical activity) can all contribute to the development of cancer.
In 2022, there were an expected 14,61,427 incident cases of cancer in India (crude rate: 100.4 per 100,000). One in nine Indians will probably get cancer at some point in their lives. The most common cancers in men and women were lung and breast cancers, respectively. The most common cause of cancer in children aged 0-14 years was lymphoid leukemia, which affected 29.2% of males and 24.2% of girls. According to estimates, the number of cancer cases will rise by 12.8% in 2025 compared to 2020.
Stages of Cancer:
To indicate the extent to which the cancer has spread throughout the body, it is categorized into various stages. Staging is typically done using a system called TNM staging and a Numbered staging system.
1. TNM Staging System:
The most widely used technique for staging cancer is the TNM system. It evaluates three essential elements:
T( Tumor):
· It describes the extent and size of the primary tumor.
· To show the degree of spread, these components are assigned a number or letter.
· T0 denotes the absence of a tumor, but T1, T2, T3, or T4 denote the presence of a growing tumor.
N (Nodes):
· Indicates if adjacent lymph nodes have been affected by the malignancy.
· To show the degree of spread, these components are assigned a number or letter.
· While N1, N2, and N3 show growing involvement of nearby lymph nodes, N0 indicates no regional lymph node involvement.
M (Metastasis):
· Denotes whether the cancer spreads to other parts of the body.
· To show the degree of spread, these components are assigned a number or letter.
· M0 indicates that there are no distant metastases, but M1 indicates that the cancer has migrated to other parts of the body.
2. Numbered staging system:
This classifies cancer according to its severity and spread using numbers 1–4.
Stage 0: Carsinoma in Situ
· The cancer has not spread to surrounding tissues; it is still contained inside its initial location.
· The initial stage of cancer is characterized by the presence of abnormal cells that have not yet spread to surrounding tissues.
· Example: Ductal carcinoma in situ in the breast.
Stage 1: Early Localized Cancer
· The tumor is small and little. No spread to distant organs or lymph nodes.
· Usually treatable with localized treatments or surgery.
· Example: No lymph nodes are involved, and the breast cancer tumor is less than 2 cm.
Stage 2: Locally Advanced Cancer
· Most of the time, cancer has not moved to distant organs or lymph nodes, but it has gotten bigger or affected tissues nearby.
· Treatment often involves a combination of surgery, chemotherapy or radiation therapy
· Example: A colon cancer tumor invading deeper layers of the colon wall.
Stage 3: Regional Spread
· The cancer has spread to tissues or lymph nodes nearby. Usually, intensive medical attention is needed.
· Example: mediastinal lymph node involvement in lung cancer.
Stage 4: Metastatic or Advanced Cancer
· The cancer has spread to distant organs, such as the brain, liver, and lungs. Although often regarded as incurable, it is treatable to control symptoms and extend life.
· Example: Prostate cancer spreading to bones.
