Custom essays on Cancer

In medicine, cancer is understood as a malignant tumor that develops from epithelial cells, (cells that cover the lining of almost all our organs and tissues). The name of the disease is associated with cancer or crab, as tumor makes outgrowths on the surrounding tissue that look like the limbs of a crab. During the cancer the normal epithelial cells of the body are transforming into tumor cells, which begin to multiply uncontrollably, and it leads to malignancy.
There are known many reasons and factors that lead to the development of malignant tumors. Approximately 80% of these causes and factors can be removed, so theoretically, 80% of cancers can be prevented (DeVita, 56).
If to try to combine all the known external factors that trigger cancer, there will be: physical factors (ionizing radiation, ultraviolet, etc.); chemical factors (carcinogens) and biological factors (some viruses). All of them initially lead to the damage of the DNA structure.
There are also internal causes of cancer. The most common case is a hereditary predisposition to cancer. Usually it is a succession of reduced ability to recover DNA, or a reduction of immunity. Sometimes the boundaries between external and internal factors become not so clear because of the impossibility of determining the primacy of their impact.
It is also necessary to distinguish between the factors and sources of exposure. The most obvious example is smoking. Tobacco is a universal source of two types of factors – physical and chemical. Strange but it is true, that smoking generates the radiation exposure of the organism. A person who smokes a pack of cigarettes a day, in addition to huge quantities of chemical carcinogens, in fact gets a double dose of irradiation every day (Delfino, 33).
The final diagnosis of malignant tumor is placed after the histological examination of tissue sample. After the diagnosis the surgical treatment, chemotherapy or radiation therapy is appointed. There also can be used such kinds of treatment as: surgical, cryotherapy, hormone therapy, immunotherapy, photodynamic therapy or combined treatment.
Without treatment, malignant tumors usually progress until the death. Most tumors are treatable, although the results of treatments depend on the type of tumor, its location and stage. Spontaneous cure rate for malignant tumor does not happen.
Malignant tumors affect people of all ages, but are more likely to occur in old age. This is one of the main causes of death in developed countries. The emergence of many tumors is associated with the effect of environmental factors, such as alcohol, tobacco smoke, ionizing radiation, some viruses (Morris, 78).
There are many types of cancer, which are classified according to the organ in which it appeared at first, the type of cells that undergo cancerous transformation, as well as the clinical symptoms. The field of medicine that deals with studying and treatment of malignant tumors is called oncology.
Thus, cancer affects different organs, so there are so many types of cancer. The most common types of cancer are: lung cancer, breast cancer, colon cancer, gastric cancer, liver cancer, prostate cancer, cervical cancer, esophageal cancer, bladder cancer, oral cancer, leukemia, pancreatic cancer, ovarian cancer, renal cancer and other.
Symptoms of cancer vary depending on the location of the tumor. The pain usually occurs only at later stages. The early stages of cancer usually don’t provide unpleasant sensations. Some common symptoms include:
Local symptoms: unusual lump or thickening; bleeding; inflammation, jaundice.
Symptoms of metastasis: swollen lymph glands, cough, possibly with blood, liver enlargement, bone pain, bone fractures, neurological symptoms.
Common symptoms: cachexia (weight loss, loss of appetite, exhaustion), immunopathological condition, hyperhidrosis, anemia (Rodgers, 36).
According to the IARC (International Agency for Research of Cancer) about 10 million of people got sick with cancer and 8 million have died from malignant tumors in 2000 worldwide (World Health Organization).
Cancer is a long, multi-staged process. Thus, the majority of tumors appear at the age of 25-40, and sometimes even in childhood. So it is the proper time to start cancer prevention. However, the chances of cure cancer depends more on how early tumor was found, the patient’s age and other factors.

Work Cited

Delfino, Michelangelo. Day, Mary E. Cancer: we live and die by radiation. 2006.
DeVita, Vincent T., Hellman, Samuel, Rosenberg, Steven A. Cancer: principles and practice of oncology. 2005.
Morris, David, Kearsley, John. Cancer: A Comprehensive Clinical Guide. 1998.
Rodgers, Joann Ellison. Cancer. 1990.
World Health Organization. National cancer control programmes: policies and managerial guidelines. 2002.