Cancer is called malignant tumors and new formations, developing from epithelial tissue. They are subdivided as follows:
- Carcinoma - a malignant tumor of skin, mucous membranes and glands.
- Sarcoma is a malignant tumor of the bone, connective and nervous tissues.
- Malignant lymphomas are diseases of the lymphatic system.
- Leukemia - the so-called. blood cancer. With the diseases of this group, the production of blood cells (most often leukocytes) is disrupted.
- Myeloma is a disease of the blood-forming organs, characterized by proliferation of plasma cells.
- Change in the emptying of the intestine and bladder.
- Poorly healing wounds.
- Unusual bleeding from the vagina and leucorrhea.
- Tumors, knots in the chest.
- Disturbance of digestion and swallowing.
- A changed wart or mole.
- Chronic cough or hoarseness.
Malignant tumors at the beginning of their development are asymptomatic. Later, there are violations of the general state: loss of strength, apathy, nausea, loss of appetite, weight loss, etc. Then there are other symptoms of the disease, for example, densification in the mammary gland, chronic stomach disease, etc. Malignant tumor grows rapidly, the patient There are painful pains. Substances to feed cancer cells come from the entire body, causing a lack of nutrition in other tissues and organs. There is a malfunction of the immune system, there are various complications, for example, pneumonia. A lethal outcome is possible.
Causes of Cancer
The main factor in the appearance of tumor formations is a genetic mutation. The change in genes can be hereditary or spontaneous, associated with exposure to various risk factors. One of the first established genes, predetermining the formation of tumors, was the gene of retinoblastoma. The cells of the human body can be transformed into cancer cells if genetic information is violated in them. However, usually this transformation is impossible: the immune system in time recognizes and destroys cancer cells. In the disorder of the immune system under the influence of the tumor, the altered cells begin to multiply without interference.
Due to the effects of electromagnetic waves, radiation or chemicals, the hereditary information stored in the cell may change suddenly (hence, a mutation may occur). If the mutant cell continues to divide, erroneous information is transferred to other generations of cells formed from it. Over time, a tumor can form from such cells.
Malignant tumor appears due to uncontrolled proliferation of cells. In contrast to benign neoplasm, cancer grows rapidly, penetrates into nearby tissues and destroys them. Cancer cells easily separate and penetrate into other organs, causing the formation of new foci of cancer (metastases). This is a symptom of all malignant tumors.
Factors contributing to the appearance of cancer
Intensive growth of tissue is facilitated by a variety of physical, chemical and biological factors. Approximately 75-80% of all cases of cancer occur due to adverse environmental effects. More than 1,000 chemicals are known to cause cancer. Physical factors are especially dangerous for ionizing and ultraviolet radiation (long-term irradiation causes skin cancer), as well as radioactive nuclides (especially strontium, which is the cause of bone cancer). Biological factors affecting the formation of a malignant tumor are oncogenic viruses. Risk factor is also malnutrition (consumption of large amounts of meat and fat).
It is estimated that around 9 million people get cancer every year and about 5 million of them die. It is estimated that in the next decade, about 20 million people will suffer from malignant neoplastic diseases, which is associated with an increase in the world population.
There are four stages of cancer. The main criteria are the size of the tumor, the damage to nearby and regional lymph nodes, the presence of distant metastases. At the first stage of cancer, the probability of recovery is greatest.
The success of cancer treatment depends to a large extent on early diagnosis of the tumor. There are different methods of treatment, there are also opportunities for slowing the development of the disease.
The tumor is removed by surgery, however, the presence of distant metastases and germination of vital organs precludes the possibility of radical surgery. In carrying out a radical operation, together with the tumor, regional lymph nodes and lymphatic vessels are removed.
Radiation therapy is the treatment with ionizing rays, which can cause functional changes in cells, tissues, organs or the whole organism. Radiation therapy of malignant neoplasms is based on the sensitivity of cells of a number of malignant tumors to X-ray and radium rays. The action of radiation radiation leads to an irreversible disruption of the viability of the tumor. Different types of tumors have different sensitivity to radiation, so the result of treatment is not the same. Ionizing radiation also acts on healthy cells. Therefore, when irradiating, it is necessary to direct the beam of rays to the tumor as accurately as possible.
The object of chemotherapy is not only individual tumors, but the entire human body. The principle of this therapy is special chemical compounds called cytostatics to influence metabolism and growth of tumor cells. Cytostatics act not only on tumor, but also on other cells of the human body. They affect the immune system, bone marrow, stomach, intestines, etc. Using cytostatics, it is possible to defeat some types of cancer.
Hormone therapy is used as a combined effect in some forms of cancer (breast, prostate). The change in the hormonal composition of the body by administering large doses of certain hormones helps delay or reverse the development of the tumor.
Probability of recovery
Applying various methods of treatment, it is possible to cure about 20% of patients. With early diagnosis of cancer, this number can be increased to 60% and even up to 100%. Therefore, regular preventive examinations are extremely important.
Benign tumors are surrounded by a capsule, grow slowly and do not metastasize. Malignant tumors grow rapidly, metastasize, destroy tissues. In the absence of treatment, a lethal outcome occurs in the shortest possible time.