Nov 21, 2016

What is Cancer?

Cancer is characterized when the abnormal cells divide in an uncontrolled way. It can start at any place in the body. The human body is made up of trillion of cells. Normally, these cells grow and divide when the body needs them. When cancer develops, these cells then divide abnormally, without stopping and form growths called Tumor. Some cancers, like Leukemia do not form tumors.

Five Main Categories of Cancer

Now that we have a basic understanding of what is cancer, let’s understand different categories of cancer.

  • Carcinomas- begins in the skin or the tissues that cover line the internal organs and gland. They form solid tumors and the most common type of the cancer. For e.g. Lung Cancer, Breast Cancer, Prostate Cancer and Colorectal Cancer.
  • Sarcomas– begins in the tissues which support and connect the body. It can develop in the fat, cartilage, bone, muscle or other connective tissues.
  • Leukemia- begins in the bone and blood marrow. It is the cancer that develops in the blood. There are four main types of leukemia, which includes Acute Lymphocytic Leukemia, Chronic Lymphocytic Leukemia, Acute Myeloid Leukemia and Chronic Myeloid Leukemia.
  • Lymphomas– begins in the lymphatic system. Lymphatic System is a network of glands and vessels that fight infection.
  • Central nervous system-cancers develop in the spinal cord and brain.

How Cancer Starts

It is very important to know what is cancer and how does it start. Cancer starts with changes in one cell or a small group of cells. Our body maintains right number of each type of cells because cells produce signals to control the division of cells. If any of these signals are missed, cells may start to grow and multiply too much and form a lump known as Tumor, where the cancer develops are known as Primary Tumor.

Leukemia, a type of cancer which starts from the blood cells, do not form solid tumors. The cancer cells build up in the blood and sometimes the bone marrow.

Certain changes occur within the genes of a cell or group of cells and causes cancer.


What is cancer and how does it cause mutations? Normally, genes make sure that cells reproduce and grow in controlled and orderly manner. Genes make sure that more cells are produced to keep the body healthy.

Sometimes change happens in the genes, when a cell divides. This change is known as Mutation. In Mutation, genes have been damaged or lost or copied twice. Mutations can be caused due to smoking or inheritance.

What is Cancer Growth?

Benign and Malignant Tumors

To understand how cancer affects human body, it is important to know what is cancer tumor. Tumors can be Benign or Malignant. Benign means it is not cancer.

Benign Tumors

  • Grow slowly
  • Do not spread to other body parts quickly.
  • Have a covering layer made up of normal cells.

Many people do not know what is cancer cell. It is noteworthy that cells of benign tumor are made up of cells that are like normal cells. They can cause problem if:

  • Grow Large
  • Press on the other body organs
  • Release hormones that affect the body function.

Malignant Tumor is made up of cancer cells. They:

  • Grow faster than the Benign Tumor
  • Spread into and damage surrounding tissues
  • May spread to other body parts through the bloodstream or lymphatic system to form secondary Tumors.

How Cancer Spreads

Now that we have understood what is cancer and tumor, let’s learn how it spreads. As the cancer cells grow, the lymphatic system or the bloodstream may carry cancer cells to the other parts of the body. This process is known as ‘Metastasis’. In this phase, the cancer cells grow and may develop into the new tumors. Lymph nodes are one of the first places where cancer spreads. They are in different parts of the body, in form of clusters such as under the arms, neck and groin area.

Cancers may also spread through the bloodstream to the different parts of the body which may include bones, liver, lungs and brain.  Even when the cancer spreads, it is still named for the area of origin. For example, if the breast cancer spreads to the lungs, it is called ‘Metastatic Breast Cancer’, not ‘Lung Cancer’.

Primary and Secondary form of Cancer

It is important to know what is cancer and its forms. A place where cancer starts is known as Primary Cancer or Primary Site. When the cancer spreads to the other body part of the new area, it is known as the Secondary Cancer or Metastasis.

Cancer spreads into the surrounding tissues

As the size of tumor grows bigger, it takes up more space in the body. Cancer may then cause pressure on surrounding body structures. It can also directly grow into body structures. This is known as ‘Local Invasion’.

Cancer can also grow into any random direction. However, tumors can spread into some tissues more easily as compared to others. For example, large blood vessels having dense tissues and strong walls like Cartilage, is difficult to grow into.

Tumors take the easiest route to grow and spread into other body parts. A tumor spreads through these three ways.

  1. Through the Pressure of the growing tissue.

As the tumor grows, it takes up more space in the body. It starts pressing the nearby body tissues; the growth of the tumor will force itself on the normal tissue. For example, cancer cells may grow between the muscle tissues rather than through the one cell.

As the cancer cells begin to grow, they block and squeeze small blood vessels in the area. Due to low oxygen level and blood level, some of the normal tissue begins to die.

  1. Using Enzymes

Normal body cells produce enzymes that break down the tissues and the cells. Cells use the enzymes to destroy the invading bacteria and viruses. They also use them to heal the damaged area.

Cancer cells contain large amount of these enzymes and contains a lot of White Blood Cells, that also produces enzymes. Cancer cells pushes and breaks down the normal tissues and it may cause bleeding.

  1. Cancer cell moving through the tissue.

Cancer cells can move easily, these cells spread to the nearby tissues by directly moving into it.

Symptoms of Cancer

This brings us to what is cancer and its symptoms. Common symptoms of cancer are:

  • Fatigue
  • Lump or thickening under the skin
  • Weight Loss
  • Change in skin color
  • Trouble in Breathing
  • Difficulty in swallowing
  • Persistent indigestion
  • Change in bowel habits
  • Presence of Blood

Common form of Cancers and their symptoms

We know what is cancer and its symptoms. It is important now to know common forms of cancer.

Lung Cancer –Smoking increases the risk of getting lung cancer, but non-smokers can also get this form of cancer.


  • Two or Three weeks of cough
  • Infection in Chest
  • Breathless
  • Blood in Coughing
  • Fatigue

Bowel Cancer– A diet high in red and processed meat can increase the risk of Bowel Cancer. A family history of bowel cancer increases the risk of getting this form of cancer.

  • Blood in Stool
  • Diarrhoea
  • Weight Loss
  • Lump in Tummy
  • Fatigue

Prostate Cancer– It is the most common form of Cancer in Men. Family History, Geographical Location (North America,Caribbean area) Diet (Red Meat, High fat dairy products)  are the risk factors that increases the chances of Prostate Cancer.


  • Difficulty in Urination
  • Week flow in Urination
  • Feeling that Bladders are still full

Breast Cancer-It is the most common form of Cancer in Women. Consumption of Alcohol increases the risk of getting this form of cancer. Family History plays another role of getting this form of Cancer.


  • Lump in the breast or armpit
  • Change is the size of Breast
  • Rash on nipple
  • Change in the skin

Melanoma – People with fair skin that burns and freckles in the sun are at higher risk of getting a type of Skin Cancer known as Melanoma.

Change of Skin and Presence of Mole is observed.

  • Change in size, shape and color of the mole
  • Mole is not symmetrical
  • Mole has more that more than one color (Brown)
  • Bleeding of Mole

Prevention from Cancer

We have learnt what is cancer and how it spreads in the body. We must now know how it can be prevented. To know this, we must know what is cancer’s origin and how it starts. Cancer is caused by DNA damage.  Lifestyle, UV Rays, Chemicals present in the Tobacco can damage DNA. With time, this damage multiplies and becomes out of control and this is how cancer starts. Few lifestyle changes can prevent cancer:

Don’t consume Tobacco

Smoking has been the major cause of various types of cancer, which includes Lung Cancer, Mouth Cancer, Throat Cancer, Larynx Cancer, Pancreas Cancer and Kidney Cancer. Chewing Tobacco has been linked to the Oral and Pancreas Cancer.

Avoid Tobacco or Just stop it.

Eat a Healthy Diet

  • Having a healthy diet can prevent you from the risk of developing cancer.
  • Eat a lot of Vegetables and Fruits

Drink Alcohol in Moderation

  • Avoid Processed Meal
  • Be physically active or maintain a healthy weight
  • Maintaining a healthy weight and being physically active reduces the chance of developing Cancer which includes Breast Cancer, Prostate Cancer, Lung Cancer, Colon Cancer and Kidney Cancer.

Protection from Sun

  • Skin Cancer is the most common form of Cancer.
  • Stay in shaded area
  • Cover the areas that are exposed
  • Avoid Tanning

Get Routine Medical Care for prevention.

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