Cancer is a dreaded disease, which is a major cause of death of human in the modern world. It is characterized by the uncontrolled multiplication and growth of cells. It may develop in any part of the body in all types of living organisms. Cancer is not a contagious disease. Cancer results from the breakdown of regulatory mechanism, which controls the normal cell behaviour. Cancerous cells are called malignant neoplasm. They directly affects the normal activities of other cells. They compete with normal cells for nutritional factors and finally destroy them. The cancerous cells may group together in masses to form tumors..
http://expertscolumn.com/content/cancer-its-diagnosis-and-treatment Causes of cancers
It is very difficult to say the exact cause of cancer in human beings. It is assumed that it is caused by the interaction of many factors and it may be the result of a chain of events. We have not been able to find the complete chain of events. We know some agents causes cancer. The agents which can cause cancers are called as carcinogens. Important carcinogens are..
1) Chemicals and radioactive rays
They cause alteration in the genetic material(DNA) resulting in the oncogenic transformations that lead to cancer. A number of chemicals that are known to make cancer. They include certain polycyclic hydrocarbons, aromatic amines, byproduct of combustion of fossil fuels, alkaloids like nicotine, caffeine, some steroid etc. Expoure to UV rays , X rays and various radioactive elements may produce cancer.
2) Tumour promoters
Some cells which had undergone genetic alternations are responsible for oncogenic transformations.These substances that promote the proliferation of this type of cells are called tumour promoters. Some growth factors and hormones are tumour promoters.
3) natural remedies to quit smoking and tobacco chewing
Heavy natural remedies to quit smoking is the major cause of lung cancer.
It is supposed some viruses such as DNA and RNA viruses induces cancers in human beings. These viruses are called oncogenic viruses.
Normally cells grow under the control of some regulatory genes. Changes in these genes causes oncogenic transformations.
Spreading of cancers
Cancerous growth starts at one location where cells proliferate to give rise to a mass of cells forming the tumour. Sometimes they may be detached and carried by the blood to the other parts of the body and spread in the new locations.
Cancer occurs at all ages in human. Early diagnosis and adequate treatment is essential for controlling this diseases. A painless lump or thickening in any part of the body , a sudden change in the size and colour of the wart, persistent cough, persistent digestive problems, excessive bleeding in women, sudden weight of body weight etc are some suspected features of cancers.
Various methods employed for diagnosis of cancer are..
1) It can be done by studying the characteristic histological features of malignant cells.
2) Blood test for abnormal WBC and bone marrow biopsy can be used.
3) X rays, CT scan and MRI scan can be used to detect cancers of internal organs like kidney, pancreas etc..
Treatment of cancer
Since cancer is not a single diseases and can caused by different ways an absolute single cure is not possible. Nowadays cancer treatment can be done in four different ways.