Basics of Cancer


Cancer is a disease that we constantly hear people discuss however, what does it entail and what effect does it has on the body. Cancer is a class of diseases caused by an uncontrolled division of abnormal cells in a part of the body. It has now become a common word that we hear but how does it affect the body.

It begins when our cells undergo genetic changes in their orderly process and cells begin to grow uncontrollably to form mass tissue called a tumour. Cancer spreads through the body in a variety of different ways such as growing into or invading nearby normal tissue, moving through walls of lymph nodes or blood vessels, travelling through the lymphatic system or blood vessels and stopping in distant blood vessels and moving into surrounding tissue.

There are five main types of cancer:
  • ·    Carcinomas. This begins in the skin or the tissue that covers the surface of internal organs and glands. Carcinomas usually form solid tumours
  • ·     Sarcomas. This begins in the tissues supporting and connecting the body
  • ·     Leukaemia. This begins when healthy blood cells change and grow uncontrollably
  • ·     Lymphomas. This begins in the lymphatic system.
  • ·    Central nervous system cancers. This develops in the brain and spinal cord


There are a few reasons as to why cancer can come back. If a tumour had been removed through surgery, it may return as some cancer cells may be left behind during the operation or they may have broken away prior to surgery however we too small to see. Cancer can return after chemotherapy or radiotherapy as these processes are unlikely to catch all cancer cells. Furthermore, cancer can become resistant to treatment. Once our normal cells become cancer cells they have to ability to continue mutating and becoming more and more abnormal. Due to this cancer cells become resistant to cancer drugs and will not respond to chemotherapy or radiotherapy. These resistant cells contain high levels of p-glycoprotein. P-glycoprotein is a protein found in cell walls. The protein acts as a pump and removes toxins from cells and keep the cancer drugs out. Unfortunately, there is currently not a of overcoming resistant cancer cells.

Fortunately, nowadays doctors do manage to cure many cancers however there is still uncertainty as the cancer could come back at any time. However, as time goes on researchers are getting closer to finding the cure.



Sources:
https://www.cancercenter.com/discussions/blog/anatomy-of-cancer/
https://www.cancer.org/treatment/understanding-your-diagnosis/advanced-cancer/what-is.html
http://www.cancerresearchuk.org/about-cancer/what-is-cancer/how-cancers-grow                
https://www.cancer.gov/types/metastatic-cancer

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