What is Cancer?

About Cancer Types Stages Causes Symptoms Screening Treatment

What is Cancer?

Cancer is a group of diseases characterized by the uncontrolled growth and spread of abnormal cells. If the spread is not controlled, it can result in death.

Cancer can affect almost any part of the body and has many different forms. Most cancers are named for the organ or type of cell in which they start.

Early detection and treatment can significantly improve outcomes for many types of cancer.

What are the types of cancer?

Cancers are usually named after the organ in which they first form. Broadly, there are four types of cancers:

Carcinoma: These are cancers that begin in the skin or the tissues that line the organs
Sarcoma: This type of cancer originates in connective tissues like bones, cartilage, blood vessels or muscles.
Leukemia: This is a cancer of the bone marrow, which is where blood cells are formed.
Lymphoma (these should/can have graphics) or Myeloma: This type of cancer attacks the immune system.

Cancers are also classified by the organs that they attack. Here are some examples of these types of cancers.

Breast Cancer

Lung Cancer

Throat Cancer

Brain Cancer

Browse more

Stages of Cancer

Cancers that involve tumours are staged in five broad groups, from 0 to 4. The stages are indicative of how advanced the cancer is.

Stage 0:At this stage, there is no cancerous growth yet. There are abnormal cells present, which have the potential to develop into cancer.
Stage 1:Also referred to as ‘early stage cancer’, at this stage the cancer is restricted to a small part of the affected organ, and has not spread to any other organ.
Stage 2 and 3:By this stage, the cancer has grown to spread into the surrounding tissues or lymph nodes.
Stage 4:Also referred to as the advanced stage or metastatic cancer, this stage indicates that the cancer has spread to other parts of the body.

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

Common Symptoms of Cancer

Symptoms of cancer can vary depending on the type and location, but some common signs include:

Unexplained weight loss
Fatigue
Persistent pain
Lumps or swelling
Changes in skin
Unusual bleeding or discharge

If you notice any persistent or unusual symptoms, consult a healthcare professional promptly. Early diagnosis can save lives.

Causes of Cancer

Cancer can be caused by a variety of factors, often a combination of genetic, environmental, and lifestyle influences.

Genetic mutations
Tobacco use
Excessive alcohol consumption
Poor diet and lack of physical activity
Exposure to radiation or chemicals
Chronic infections

Many cancers can be prevented by making healthy lifestyle choices and avoiding known risk factors.

What are the different screening tests for cancer?

Screening for cancer refers to undergoing tests for early detection of cancer in apparently healthy population even before the symptoms start to show. Each type of cancer has specific screening tests. Here are some common ones.

Colonoscopy and Sigmoidoscopy:

These tests can detect any abnormal growth in the colon even before it becomes cancerous. Thus, it just not helps in early detection of cancer but also in the secondary prevention of cancer. It is recommended that those at risk of colon cancer undergo these tests after the age of 50.

Mammography

This test is used to screen for breast cancer. It can identify lumps in the breast even before these lumps can be felt through self-examination. Although this test cannot prevent cancer, it allows for early detection of cancer, making it easier to treat.

Low-dose Computed Tomography

This test screens for lung cancer. It is recommended that heavy smokers and former heavy smokers undergo this test once they are over the age of 55.

Pap Test and Human Papillomavirus Test (HPV)

These tests are conducted alone, or in combination, to screen for cervical cancer. It is recommended that women above the age of 21 undergo this test. It allows for the prevention as well as early detection of abnormal growths, even before they can become cancerous.

Alpha-fetoprotein Blood Test

This test is recommended for those at high risk of liver cancer. Usually, this is done in combination with an ultrasound of the liver.

What are the treatment options for cancer?

Treatment depends on the type and stage of the cancer, as well as the overall health of the patient. While some patients may be given just one type of treatment for their cancer, most patients undergo a combination of two or more types of treatments.

There are three main treatment options for cancer:

Surgery

This is one of the oldest types of cancer treatments and is still primary treatment used today for most types of cancer. Surgery involves removing the tumor from the body. Surgery may be conducted to take a sample of the tumor, to know the type and stage of cancer. It may also be conducted to remove the entire cancerous growth, or a part of it, from the body. Sometimes, surgery is undertaken to reduce the symptoms of cancer in the patient, thereby improving their quality of life.

Radiation Therapy

This involves the use of high does of radiation to kill cancer cells or shrink tumors. This therapy often uses high energy x-rays or gamma rays, but protons or other types of energy may also be used.

Radiation therapy destroys the genetic material that controls the growth of cells. It affects both the healthy and the cancerous cells but the healthy cells are able to recover from the damage.

Chemotherapy

Chemotherapy uses chemicals to destroy cancer cells. Sometimes a single drug is used for this, but more often a combination of drugs are used in a certain order, to maximize their effect. Chemotherapy is administered through implants, oral medication, injections or through localised treatments, including creams.

There are advanced treatments for cancer available now. These include immunotherapy, targeted therapy, hormone therapy, stem cell transplant and precision medicine.