Cancer

1
Cancer

• Cancer is one of the most common diseases in the
  developed world
• 1 in 4 deaths are due to cancer
• 1 in 17 deaths are due to lung cancer
• Lung cancer is the most common cancer in men
• Breast cancer is the most common cancer in women
• There are over 100 different forms of cancer

2
Cancer

• The division of normal cells is precisely
  controlled. New cells are only formed for growth
  or to replace dead ones.
• Cancerous cells divide repeatedly out of control
  even though they are not needed, they crowd out
  other normal cells and function abnormally. They
  can also destroy the correct functioning of major
  organs.

3
What causes cancer?

• Cancer arises from the mutation of a normal gene.
• It is thought that several mutations need to
  occur to give rise to cancer
• Cells that are old or not functioning properly
  normally self destruct (apoptosis) and are
  replaced by new cells.
• However, cancerous cells do not self destruct and
  continue to divide rapidly producing millions of
  new cancerous cells.

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• A factor which brings about a mutation is called
  a mutagen.
• A mutagen is mutagenic.
• Any agent that causes cancer is called a
  carcinogen and is described as carcinogenic.
• So some mutagens are carcinogenic.

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Carcinogens

• Ionizing radiation X Rays, UV light
• Chemicals tar from cigarettes, some pollutants
• Virus infection papilloma virus (HPV) can be
  responsible for cervical cancer.
• Hereditary predisposition Some families are
  more susceptible to getting certain cancers.
  Remember you cant inherit cancer its just that
  you maybe more susceptible to getting it.

6
Benign or malignant?

• Benign tumours do not spread from their site of
  origin, but can crowd out (squash) surrounding
  cells,
• eg. brain tumour, warts.
• Malignant tumours can spread from the original
  site, travelling through the blood stream or
  lymphatic system and cause secondary tumours.
  This is called metastasis. They interfere with
  neighbouring cells and can block blood vessels,
  the gut, glands, lungs, etc.
• Both types of tumour can tire the body out as
  they both need a huge amount of nutrients to
  sustain the rapid growth and division of the
  cells.

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Abnormal Cell Growth
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Abnormal Cell Growth
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A Large Abdominal Tumour
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Surgical Removal of Tumour
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Body without Tumour
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Cancer (CARCINOMA) of the Tongue
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Advanced Tumour Formation
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Basal Cell Carcinoma Skin cancer
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More Skin Cancer
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Lip Cancer
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Cancer Treatment

• Two basic treatments surgery to remove the
  tumor, and radiation or chemicals to kill
  actively dividing cells.
• It is hard to remove all the tumor cells. Tumors
  often lack sharp boundaries for easy removal, and
  metastatic tumors can be very small and anywhere
  in the body.
• Radiation and chemotherapy are aimed at killing
  actively dividing cells, but killing all dividing
  cells is lethal you must make new blood cells,
  skin cells, etc. So treatment must be carefully
  balanced to avoid killing the patient.
• Chemotherapy also has the problem of natural
  selection within the tumor. If any of the tumor
  cells are resistant to the chemical, they will
  survive and multiply. The cancer seems to have
  disappeared, but it comes back a few years later
  in a form that is resistant to chemotherapy.
  Using multiple drugs can decrease the risk of
  relapse its hard for a cell to develop
  resistance to several drugs at the same time.

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Cancer prevention

• Healthy Lifestyle
• Low fat, high fiber diet
• Exercise
• Not smoking
• Taking daily vitamins and minerals
• Vitamins A, C, E, and calcium