Cancer cell

Cancer represents a large group of diseases that can affect any part of the body. It is the leading cause of death worldwide. According to the World Health Organization, a defining feature of cancer is the rapid growth of abnormal cells that grow beyond familiar boundaries, which can spread to other organs. The latter process is known as metastasizing.


The most common types of cancer death are:

  • Lung
  • Liver
  • Stomach
  • Colorectal
  • Breast; and
  • Oesophageal cancer


Cancer is formed from one single cell. The World Health Organization states that the process from a normal cell into a tumor cell is the result of the interaction between a person's genetic factors and 3 categories of external agents, including:

  • Physical carcinogens, such as ultraviolet and ionizing radiation;
  • Chemical carcinogens, such as asbestos, components of tobacco smoke, aflatoxin (a food contaminant) and arsenic (a drinking water contaminant); and
  • Biological carcinogens, such as infections from certain viruses, bacteria or parasites.


Risk factors for cancer are:

  • Tobacco use
  • Alcohol use
  • Unhealthy diet
  • Physical inactivity


Cancer can be reduced through implementing evidence-based strategies and knowing how to detect the disease ahead of time.


According to the World Health Organization, key risk factors of cancer are:

  • Tobacco and alcohol use
  • Being overweight or obese
  • Unhealthy diet with low fruit and vegetable intake
  • Lack of physical activity
  • Sexually transmitted HPV-infection
  • Infection by HBV
  • Ionizing and non-ionizing radiation
  • Urban air pollution; and
  • Indoor smoke from household use of solid fuels


If cancer is detected and treated early, the chance of mortality can be reduced. Two types of early detection efforts are early diagnosis and screening. An early diagnosis involves being aware of early signs and symptoms for types of cancers such as breast, cervical, colorectal, and oral, in order to be diagnosed and treated at an early stage. Screening involves identifying the individual with abnormalities related to a type of cancer and referring them for proper treatment.

According to the World Health Organization, some screening methods are:

  • Visual inspection with acetic acid for cervical cancer in low-resource settings
  • HPV testing for cervical cancer
  • PAP cytology test for cervical cancer in middle- and high-income settings; and
  • Mammography screening for breast cancer in high-income settings.


Every type of cancer requires a specific treatment, therefore, a proper diagnosis must be conducted.

Chemo treatment  

When detected and treated early, the following cancers have high cure rates according to optimal practices, including:

  • Breast
  • Cervical
  • Oral; and
  • Colorectal cancer


Cancer treatment

Besides treatments to cure cancer, there is also a treatment to relieve symptoms caused by cancer, known as palliative care. This type of care allows cancer patients to live more comfortably and it is needed in areas where people have a minimal chance of cure.


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Cancer description, symptoms, and treatments.