Cancer is known as an abnormal growth of cells, as cancer cells are represented by an abnormal shape and functional disorder, and rapid growth compared to normal cells in the body, and these cells can move to other parts of the body, forming tumors. It is an abnormal collection of cells that the body cannot control the rates of division and growth. Tumors are divided into malignant or cancerous tumors and benign tumors. The growth of polyps is confined to a specific area of the body and has a low growth rate.
Changes to normal, non-cancerous cells
Before expanding the interpretation of cancer cells, it is worth noting the possibility of some abnormal changes in the cells of the body, which are not classified as cancer cells, but some of these changes may lead to the development of the cell into a cancer cell in the absence of appropriate treatment. For some of these changes:
Hyperplasia expresses a higher rate of cellular proliferation or division than the normal percentage of cells, which leads to their accumulation, and it is worth noting that tissues affected by hyperplasia do not show any abnormal signs when detected using a microscope, and there are several health problems and factors that may lead to To hyperplasia, such as chronic irritation in a tissue.
Dysplasia is similar to hyperplasia, except that the shape of cells and tissues appears abnormal when detected using a microscope in this case, and the problem of dysplasia is more serious, which requires monitoring and treatment in some cases, as the chance of these cells turning into cancer cells These cells and tissues become more deformed when detected, and examples of dysplasia are an abnormal mole or birthmark known as a dysplastic nevus, which in some rare cases may turn into melanoma or melanoma.
- Absolute carcinoma:
Although the term carcinoma in situ appears to express a type of cancer, this type of cell disorder is not considered cancer despite its extreme seriousness, as these cells do not have the ability to spread to neighboring tissues But in some cases, they may develop into cancer cells, so most cases of metastatic carcinoma are treated to prevent their progression.
Causes of cancer
It is not possible to identify a major cause of cancer, but scientists believe that many different factors may cause cancer, such as environmental and genetic factors, and the unique structural characteristics of a person. As for the mechanism of the transformation of a cell into a cancer cell, scientists believe that this transformation occurs as a result of the combination of several genetic mutations in The genetic material of the cell, especially the mutations that affect the part responsible for directing the cell to growth and division, as any error in the instructions that stop the cell from performing its normal function may allow the cell to turn into a cancer cell, and many different reasons may lead to these mutations, And gene mutations can be divided into mutations that occur before birth that are inherited from the parents and are responsible for only a small percentage of cancer cases and acquired genetic mutations that occur after birth and are responsible for a greater proportion of cancer cases, and these mutations may occur for many reasons such as Exposure to some chemical elements, radiation, viruses, smoking, and an unhealthy lifestyle. Exercise is practiced, and the person suffers from obesity, in addition to some hormonal disorders and chronic infections, and here it should be noted that the different cells of the body have a defense mechanism that protects them from these mutations and disorders that affect the genetic material, but in some rare cases, the cells may not be alerted. To these disorders, which leads to their transformation into cancer cells, and in what follows an explanation of some of the common effects that may occur in the cell as a result of exposure to genetic mutations:
Some genetic mutations may cause the cell to lose its ability to regulate the process of growth and division, which leads to hyper-division and growth and the formation of new cells bearing the same genetic mutation.
- Loss of ability to inhibit cell growth:
Some genetic mutations affect the carcinogenesis suppressor genes, which is the gene responsible for inhibiting the growth and division of the cell when it reaches the normal limit, and this, in turn, leads to a loss of control over the growth and division of the cell when it reaches the normal limit, which is what happens in a cancer cell, which leads to the spread of cancer. In normal cases, the growth and division of cells are within a specified rate so that one type of cell does not overwhelm other cells in the body.
- Disruption of the genetic repair process:
The function of some genes, in particular, is to repair disorders in the genetic material of the cell, and in the event of mutations in these genes, the repair process may be stopped, which leads to an increase in errors in the genetic material of the cell and an increased risk of it turning into a cancerous cell. It is worth noting that a cell does not usually transform into a cancer cell except when it is afflicted with several genetic mutations, and scientists have not been able to determine the number of these gene mutations so far, and it is believed that the number of mutations that cause cancer depends on the type of cancer, although some are inherited May increase the risk of cancer, these mutations do not necessarily mean that a person has cancer. Rather, this person may need in this case a smaller number of acquired gene mutations to transform the cell into a cancer cell.
Types of cancer
Cancer can be divided into two main types, namely, cancers that affect the blood and blood-producing tissues of both types, leukemia, and lymphoma, or lymphoma, and solid cancers that affect other different body tissues, and they are divided into carcinomas and malignant muscle tumors or sarcomas. A breakdown of these different types:
- Lymphoma and leukemia: Cancerous lymphoma cells arise within the lymph nodes and cause large masses of tumors to appear in areas of the proliferation of the lymph nodes, such as the chest, armpits, abdomen, and upper thigh. As for leukemia or leukemia, it arises from the cells responsible for producing blood in the bone marrow, which affects its ability to produce Normal blood cells.
- Carcinogenesis: This type of cancer affects the elderly at a higher rate than the youth, and it arises within the cells lining the internal organs, lungs, digestive system, and skin, so many different types of cancer such as thyroid cancer (such as thyroid cancer), prostate, colon, breast, and skin, fall within this type. And lungs.
- Sarcoma: unlike cancer, this type of cancer is more common in younger people compared to the elderly, and this type of cancer arises within the cells of the mesoderm, which is one of the types of cells that enter the formation of connective tissue, muscles, bones, and blood vessels, Examples of this type of cancer include osteosarcoma or osteosarcoma, and leiomyosarcoma. It is cancer that arises within the smooth muscles of the stomach.