Table Of Content

What Is Cancer?

Cancer is a disease characterized by uncontrolled and abnormal division (proliferation) of cells. Cancer can begin anywhere in the body and even spread to other body parts.

The human body is made up of trillions of cells. These cells are the “building blocks of life,” constituting the basic structural unit of any organism. New cells are formed when these cells divide and grow. Upon growing old or getting damaged, these cells die, and the new cells replace them. When this pattern of cell division gets disrupted, and when they start proliferating abnormally, cancer develops.

The continuous division of these cells can form tissue masses, which become a tumor. These tumours are either benign or cancerous. If benign, the tumour can grow, but it does not spread and can be removed. After removal, a benign tumour might not grow back. However, if cancerous, the tumor can spread to other parts of the body. This is known as metastasis, where cancer can spread to other vital organs like lungs, brain, liver, etc., and become fatal.

What Are The Types Of Cancer?

Cancers are usually divided based on where they begin. The various types of cancers are:

1. Carcinomas: This type of cancer begins in the skin of the tissues lining the internal organs. They are of two types, adenocarcinoma, and squamous cell carcinoma.

  • Adenocarcinoma: It is a type of cancer that begins in the cells of glands lining the insides of the organs. It forms in the glandular epithelial cells responsible for the secretion of mucus, digestive juices, and other fluids.
  • Squamous cell carcinoma: It is a type of cancer beginning in the squamous cells. These cells are thin and flat and are found in the skin and the linings of respiratory and digestive tracts.

2. Sarcoma: It is a type of cancer originating from the connective tissues like bones, cartilage, blood vessels, lymph vessels, muscles, or joints.
3. Leukemia: It is a type of cancer occurring in the bone marrow which is responsible for the production of blood cells.
4. Lymphoma: It is a type of cancer that starts in the lymphatic system (lymphocytes).

What Are the Stages Of Cancer?

There are five stages of cancer, stage 0 to stage 4. These stages indicate how advanced the cancer is. Staging cancer helps the doctor in the planning of treatment. The stages of cancer are:

  • Stage 0: In this stage, the cancer is located at its site of origin and is otherwise also described as cancer in situ (in place). Cancer has not spread to nearby tissues at this stage and can often be cured.
  • Stage 1: In this stage, the cancer is small and has not spread into any other organ. It is also referred to as “early-stage cancer.”
  • Stage 2: In this stage, cancer has grown but has not spread into the nearby tissues. At certain times, it might have spread into the lymph nodes nearby the tumor.
  • Stage 3: In this stage, cancer has grown large and may have spread into the nearby tissues and lymph nodes.
  • Stage 4: In this stage, cancer has spread to other organs from its origin. This stage is also known as the advanced stage or metastatic cancer.

Cancers that are not related to tumor growth follow their own staging system. Such cancers include blood cancer and lymphoma.

What Are The Causes Of Cancer?

The exact causes of cancer are difficult to determine. But certain risk factors increase the risk of developing cancer. They are:

  • Aging
  • Family history
  • Smoking and tobacco use
  • Alcohol consumption
  • Infection of certain viruses (like human papillomavirus (HPV), hepatitis B and C virus)
  • Long-term, unprotected UV light exposure
  • Exposure to radiation
  • Unhealthy diet and eating habits
  • Lack of physical activity
  • Obesity
  • Hormones
  • Exposure to certain chemicals

Factors like aging and family history cannot be controlled. However, risk factors like smoking, using tobacco, alcohol consumption, an unhealthy diet, etc., can be controlled to prevent cancer.

What Are The Symptoms Of Cancer?

The signs and symptoms of cancer vary depending upon the affected body part or organ. However, some common cancer symptoms include:

  • Fatigue
  • Sudden unexpected and unexplained weight loss or gain
  • Skin changes like yellowing, redness, or darkness
  • Development of sores that don’t heal or changes in an existing mole
  • Blood in stools
  • Persistent change in urine or stool routine
  • Persistent heartburn or indigestion
  • Lump or thickening in the breast
  • Unexplained bleeding or bruising
  • Painful urination or blood in the urine
  • Persistent fever or night sweats
  • Nausea and vomiting
  • Difficulty swallowing
  • Sudden unexplained muscle or joint pain
  • Persistent coughing or hoarseness
  • Chronic persistent headacheAging

If any of the symptoms persist, consult your healthcare provider immediately.


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