What is Cancer? How Cancer Starts?

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What is Cancer? How Cancer Starts?

What is Cancer? How Cancer Starts?

In one’s body, there are normal cells that grow and divide. They can also stop growing or can die. Sometimes old cells do not die and can grow out of control and multiply to form a lump of tissue, called a tumour. There are two types of tumours—malignant, which is cancerous and the other is Benign- noncancerous. The cancerous tumours mix with tissues near them and grow, and as they keep moving in the body they form the secondary tumours and the spread of cancer starts.

Beginning of Cancer: 

Cancers begin in cells. All cancer cells have gene mutations. This may be inherited, or when genes wear out or as we get older or if our genes get damaged because of smoking, consuming alcohol or because of the ultraviolet rays of the sun, obesity is also a cause of cancer, and even lack of exercise can be a cause of cancer.

How do Cancer Cells Look: 

Cancer cells look different from normal cells. Normal cells have the same size and shape, whereas cancer cells sizes and shapes are different and divide out of control, they also act differently. So, it has to be closely watched and treated by a doctor. All of us need not be afraid because every one of us doesn’t have cancer cells in our bodies. Our bodies continuously produce new cells, and some of them can become cancerous. If they are arrested at the right time with the right treatment, the spread of cancer can be stopped and cured.

Growth of Cells and Division:

Cells keep growing and dividing eg. Skin cells. Skin cells continuously make new cells and replace the ones lost. We lose about 50 million cells every day. Nerve and brain cells do not divide that often. There are two ways how cells divide- one is mitosis—which is a single cell that divides into two cells that look alike and have the same number of chromosomes. The other is meiosis—in this, the cell divides into four cells and has half the number of chromosomes.


Mutations in genes can cause cancer. This can occur at any time in one’s life. Mutations are present only in some cells of the body and not in all the cells. The changes in the cells can be caused by the ultraviolet radiation from the sun, or when an error is made as DNA copies itself during cell division.

There are two types of mutations – inherited mutations –from mother or father to their child. The other is acquired mutation—is connected to the environment for e.g. if a skin cell or knee gets scraped, new cells are replaced that can contain the mutation. This mutation is not passed on to the children.

Normal and Cancer Cells:


Normal body cells reproduce themselves whenever needed and stick together. When they become old they destroy themselves, whereas cancer cells differ in a number of ways from normal cells. Cancer cells continue to grow and divide to form a lump (tumour). In the case of leukaemias, tumours are not formed but many abnormal blood cells will build up in the blood. Normal cells mature and carry out their function in the body. Cancer cells do not mature and so don’t function properly and they divide and grow quickly.

Cancer Cells Don’t Repair Themselves Die:

Normal cells can repair themselves if their genes get damaged. In cancer cells, the molecules present in them decide whether a cell can repair itself or die, so they don’t repair themselves properly, and they grow faster, spread fast to the other parts of the body and are resistant to treatment. Cancer cells also look different in size and have an abnormal shape, unlike the normal cells.

Types of Cancers: 

There are various types of Cancers.  The main types of Cancer are—

Carcinomas: This cancer starts in the skin or in the tissues that cover the internal organs of the digestive system, chest and abdominal cavities. This is the most common type of cancer.

Sarcomas: This cancer starts in the supportive tissues, like in the bone, cartilage, fat, muscle or in the blood vessels. This is much less common than carcinomas.

Leukaemias: Cancer of the white blood cells. It starts in the tissues that make blood cells, like in the bone marrow. Leukaemias are uncommon in adults but common in children.

Lymphomas and Myeloma: These cancers start in the cells of the immune system, in the glands or any other organ of the body and can start anywhere. Lymphomas, in the white blood cells, divide abnormally and don’t die. They collect in bone marrow or the spleen and grow into tumours. Myeloma starts in the plasma cells, a type of white blood cell made in the bone marrow.

Brain and Spinal Cord Cancers: These cancers are also known as central nervous system cancers. These cancers can start in the brain or spinal cord. Some of the tumours that grow in the central nervous system are benign(non-cancerous) and grow very slowly, whereas malignant (cancerous) grow very fast.

Awareness On Cancer: 

Every study that was conducted reveals that awareness and knowledge of all types of cancers are very low. Cancer, for most, is something only caused by tobacco use. The knowledge that people gather is either from television or from friends and relatives. Though cancer camps are held regularly, people hardly attend to enhance their knowledge or clarify their doubts.

Hence it is important to create awareness from childhood. At school-level, such topics can be included in their curriculum, as today’s generation is quick in grasping, spreading the knowledge and adopting the risks to get themselves and their near and dear ones cured. Awareness camps can be conducted area wise very often regarding causes, diagnosis, treatment and prevention of cancer. Unfortunately, the awareness of various cancers like Skin Cancer, Prostate Cancer, Colorectal Cancer, Kidney Cancer, and Bladder Cancer and so on is very low. The only cancers that people are aware of are lung and breast cancers. Many educated people are also not aware that men are also prone to Breast Cancer. Lack of knowledge about various types of cancers and people’s relaxed attitude should be dealt with on a war footing.