Cancer can occur in quite varied forms and variants of course. Often, cancer is perceived as a death sentence, but in reality not all malignant tumors lead to death. Moreover, modern research has demonstrated that each of us in the body regularly have the cancer cells or even microscopic cancers growing, which are killed and will dissolve under the influence of the system of antitumor immunity. However, malignant tumors have claimed many lives and, of course, require the most serious attention.
Causes of Cancer
The basis of the cancer disease is a violation of regulation processes of tissue growth.
The cells in our body constantly grow and divide to replace damaged or old cells. When a cell divides and is updated there is always a probability of error.
Our body is equipped with a mechanism for preventing and correcting these errors, but it can fail. This is most likely when exposed to carcinogens (substances that promote cancer), trauma (physical, thermal or otherwise), as well as unfavorable conditions for the functioning of these mechanisms (e.g., hypoxia – lack of tissue oxygen). If the mechanism of control of cell division “breaks”, there is uncontrolled growth and division, which is referred to as “cancer”.
A benign tumors From cancer has three key differences, which cause the “malignancy” of the process:
- uncontrolled growth,
- germination (invasion) to surrounding tissue and organs
- ability to metastasize – the process of migration of cancer cells through the blood or lymph to other parts of the body.
In most cases, cancer takes the form of a tumor, but sometimes, for example, in the case of blood cancers, the tumor as such is not formed.
Oncology and Cancer Treatment
Unfortunately, cancer can occur in any living organism and at any age, however, this risk increases over time – it is believed that more than 64% of cancers are identified in people older than 65 years.
The most unpleasant that the resulting “error” is often have the ability to run similar mechanisms in other, hitherto healthy cells. For example, a mutation in the system signaling interaction between the cells can make it release substances that will be like a “command” to neighboring cells to start a similar “mistake”.
This is one of the reasons why cancer is so difficult to treat. You can destroy the different curative effects of 10 million cancer cells, but if you survive at least a few, the malignant process will continue — they again start to share and/or send incorrect signals to other cells, starting the whole vicious circle again.
Development of Cancer
Mutations in the cell can occur for different reasons, either during errors during the division of DNA under the influence of different factors (and sometimes spontaneously) or can have hereditary nature.
Effect of Carcinogens on Cancer
One of the most important mechanisms of development mutations is exposure to carcinogens — substances that cause cancer or increase the likelihood of its development. People have always had cancer, but the recent increase in the incidence, in all probability, directly connected with increase of human contact with such substances. Some of them are direct mutagens, ie, by themselves cause DNA damage (e.g. asbestos or tobacco smoke components). Others, such as alcohol, act indirectly, for example, increasing the rate of cell division. Thereby creating the conditions in which the protective mechanisms just don’t have time to deal with “error correction”.
Impact of Viruses on Cancer
There is evidence that at least 15% of all cases of cancer one way or another associated with exposure to viruses, e.g. human papilloma virus (cervical cancer) or hepatitis viruses B and C (liver cancer). They occupy second place in the structure of risk factors after smoking tobacco.
Mutations can also occur under the action of ionizing radiation. It is known that the probability of developing melanoma depends on the intensity of ultraviolet radiation received by man. According to the statistical research conducted in the UK, the frequency of skin cancer among pilots and crew members of the aircraft was higher than that of other professions.
The products that we use also affect the risk of developing certain types of cancer. For example, in Japan, most often stomach cancer, and in the U.S. – colon cancer. And immigrants within the first generation risks are equal the risks for the people of the new country of residence that confirms the hypothesis of a genetic predisposition.
According to the recently published data of Cancer Research UK, found a link excess weight and cancer. The body mass index of over 30% in women increases the risk of developing some cancers by 40%.
Heredity also plays a role. For example, mutations in the BRCA1 and BRCA2 genes significantly increase the risk of developing breast cancer and ovarian cancer. There is also evidence of genetic susceptibility to some other cancers.
Other contributing factors may be violation of hormonal regulation, immunodeficiency States (e.g. AIDS), etc.
At the moment, Oncology is one of the most rapidly developing areas of medicine. In recent years there are many drugs and techniques that help to effectively treat cancer, prolong life of patients, improve the quality of life.