What It Is
Contrary to popular belief, Cancer is not one disease. It is a CLASS of diseases in which a group of cells exhibit following traits:
1) Uncontrolled growth i.e. growth and division beyond normal limits.
2)Invasion i.e. intrusion on and destruction of adjacent tissues.
And in some cases,
3) Metastasis i.e. spread to other locations in the body via lymph or blood.
In fact, it is because of above three properties that medical fraternity is able to differentiate cancer from benign tumors. Benign tumors are self-limited,
do not invade or metastasize. Barring exceptions like leukemia, most cancers form tumors.Cancer can affect people of any age. However, the risk for cancer tends to increase with age. Cancer is responsible for about 13% of all deaths. Cancer is not limited to humans alone and can affect other animals and even plants!
Intake of carcinogens such as tobacco smoke or exposure to radiation, chemicals or infectious agents causes abnormalities in the genetic material of
transformed cells. Other sources of genetic abnormality could be through errors in DNA replication or it could be inherited.
Treatments available for cancer are surgery, chemotherapy, radiation therapy, immunotherapy, monoclonal antibody therapy and other methods. The choice
of therapy is decided by the location and grade of the tumor and the stage of the disease, as well as the general state of the patient. Many experimental cancer
treatments are also under development.
The reason why doctors hesitate to resort to surgery is the propensity of cancers to invade adjacent tissues. Drawback of chemotherapy is its toxicity to other
tissues in the body. Radiation also has the limitation that it causes damage to normal tissue.
Surgery: This is used for small cancers. Sometimes entire organ has to be removed.
Radiation: Radiation therapy injures or destroys cells in the area being treated (the “target tissue”) by damaging their genetic material, making it impossible for these cells to continue to grow and divide. Although radiation damages both cancer cells and normal cells, most normal cells can recover from the effects of radiation and function properly. The goal of radiation therapy is to damage as many cancer cells as possible, while limiting harm to nearby healthy tissue. So we see that radiation therapy is not without its side-effects. Hence, it is given in many fractions, allowing healthy tissue to recover between fractions. Radiation is generally resorted to while treating solid tumor, including cancers of the brain, breast, cervix, larynx, lungs, pancreas, prostate, skin, stomach, uterus,…
Chemotherapy: In this method, doctors try to treat cancer with the help of “anticancer drugs”. These drugs try to interfere with cells’ ability to multiply. The
interference could be in form of not allowing duplication of DNA or separation of newly formed chromosomes. However, the drugs target all rapidly dividing
cells. Still it is used because cancer cells cannot repair DNA damage while while healthy cells can do so. This therapy is also known to damage bone marrow.
Targeted therapies: Targeted therapy, which first became available in the late 1990s, has had a significant impact in the treatment of some types of cancer, and is currently a very active research area.
Immunotherapy: Here, effort is made to increase the patient’s immunity to diseases and thus enable him to fight the disease on his own.
Hormone therapy: By providing or blocking certain hormones, growth of some cancers can be retarded. This therapy is used in cases like breast and prostate