cancer

• Carcinogens


  Substances that may increase your risk of developing cancer.
• Cancer:


  A Condition developed from mutations in DNA / uncontrolled cell growth & division, leading to the formation of tumours.
• Benign tumours:

  Growth of abnormal cells.

  • Contained in one area, usually within a membrane
  • They do not invade other parts of the body.
  • not cancerous
• Malignant tumours

  Cancerous

  • invades neighbouring tissues
  • spreads to different parts of the body in the blood, where they form secondary tumours.

  They're considered as cancer.
• Risk factors for cancer

  • Smoking
  • Obesity
  • UV exposure
  • Viral infections
  • Age
  • Diet
  • Body weight
  • Alcohol
• Chemotherapy


  Drugs are used to destroy cancer cells, can also be healthy cells, used to control and ease symptoms.
• Radiotherapy


  High energy radiation is used to shrink tumours and kill cancer cells by damaging their cells.
• Cryosurgery


  Used on external tumours, retina, cervix and early stage prostate cancer, liquid nitrogen, dissolves and forms a scab, can affect fertility and can cause scarring.
• • Normally cells grow and divide by mitosis, but when a cell becomes cancerous, it begins to divide uncontrollably
  • New cells are produced even though the body doesn't need them.
  • The extra cells form a growth called a tumour, which are solid.
• Reasons why survival rates for cancer has increased

  • Improved treatment/Drugs
  • Earlier Diagnosis
  • Improved patient knowledge
  • More cancer screening
• Tumours may spread to other parts of the body by the blood/circulatory system.
• The risk factor that increase the likelihood of developing cancer can be:

  • LIFESTYLE-RELATED
  • GENETIC
• Lifestyle-Related Risk Factors:

  • Smoking
  • Obesity
  • UV Exposure
  • Viral Infections
• Smoking cause:

  • lung cancer
  • mouth cancer
  • cervical cancer
  • stomach cancer
• Obesity cause:

  • breast cancer
  • liver cancer
  • kidney cancer
  • bowel cancer
• Genetic Risk Factors:


  Inherited genes can make individuals more susceptible to cancer.

  • e.g. mutations in the BRCA genes increase the risk of breast & ovarian cancers.
• Tumour:


  An abnormal mass of cells that forms when a group of cells undergo uncontrolled growth and division. 

  • Tumour cells divide by mitosis.
• There's two types of tumours:

  • benign
  • malignant
• Types of risk factors have been linked to cancer:

  • Lifestyle factors
  • Environmental factors 
  • Genetic factors
• Similarities between benign & malignant tumours:

  • Result from changes in the cell
  • uncontrolled cell division
  • can form a lump of cells
  • made up of abnormal cells
• Interphase is the stage of the cell cycle which DNA is replicated.