Cancer (Latin cancer, carcinoma, from the Greek karkinos — cancer, crab) — a malignant tumor from the epithelium, that is, from the tissue that covers the animal organism from the outside and lining it from the inside, as well as its forming glands. Therefore, cancer is a malignant tumor (tumor, blastoma) of the skin, digestive tract, respiratory and urinary tract, lungs, kidneys, liver, genitals and glands. The name given by the doctors of the middle ages, is associated with the appearance of a tumor resembling cancer or crab. Cancer accounts for the vast majority of all malignant human tumors, including many sarcomas, hematological malignancies, glial tissue, bone, and other tumors. In some countries, cancer is understood as any cancer.

The occurrence of cancer

The tumor occurs due to metabolic disorders in the cells and the weakening of the control of intracellular processes by the body. As a result of the acquisition of new qualities and partial independence from the regulatory systems of the body, young dividing cells lose the ability to differentiate — they do not acquire proper functions and do not form a normally working tissue. Not participating in the life^[ru] of the body, such cells become unnecessary to him, unnecessary. The body tries to get rid of them with the help of immune reactions, which are not always effective. The excess of young, all the time multiplying, but not working cells, besides requiring an increasing amount of energy and food resources, leads to the fact that such cells attack their tissue or organ. These cells (they are called tumor) are introduced into the tissues of the body, infiltrate (see Infiltrate) and destroy them, capture blood and lymph vessels, which are distributed throughout the body — metastasize (see Metastasis).

Cause of cancer. Oncogenesis

About the reasons of occurrence of tumor is known not all. The predisposition to cancer of an organ (for example, breast, stomach) is inherited, that is, it is of a family nature. Inherited hormonal abnormalities in the body or local structural disorders in any organ (intestinal polyposis, birthmarks on the skin, etc.). These abnormalities and irregularities can lead to the development of the tumor, which was noted more than a hundred years ago by the German pathologist Julius Friedrich Conheim. However, for the emergence of tumor — oncogenesis — tissue deformities alone is not enough. Mutagenic stimuli causing changes in the hereditary apparatus of the cell and then tumor transformation are needed. Such incentives can be internal (e.g., increased production of hormones or other metabolic products, their imbalance) or external — physical (e.g., ionizing or ultraviolet radiation), chemical, viral, etc. These factors have mutagenic and thus carcinogenic exposure that triggers the mechanism that produces cancer cells in ever increasing numbers.

It is believed that any cell has a tumor growth program. This program is recorded in special genes — oncogenes. Under normal conditions, oncogenes are tightly blocked (repressed), but under the influence of mutagens, the blockade can be removed, and oncogenes are able to work. It is also known that many carcinogens suppress the immune system of the body, releasing from its rigid and constant control deviated cells. Control and restoring functions of the immune system sharply weaken in old age, when most often there is a malignant tumor.

Form of cancer

Cancer tissue is a very mobile and changeable formation. Its behavior depends on many factors, including the intensity of protective anticancer reactions, which the body is capable of in a particular case. The human immune system can partially or completely destroy the tumor. It can also block cancer cells at an early stage and prevent them from penetrating deep into the organ (non — invasive cancer, or “cancer in place” in situ”). In the name of the form of cancer are reflected: belonging to a particular organ (lung cancer, ovarian cancer, etc. e.), the type of epithelium, serving as a source of tumor (squamous cancer, glandular — adenocarcinoma, basal cell, etc.), the growth rate, histological equivalent of which is the degree of maturity of cancer tissue (cancer differentiated and undifferentiated), properties associated with the degree of maturity of the tumor and the effectiveness of immune reactions in it (cancer aggressive, stable, regressive).

Clinic, diagnosis, cancer prevention and treatment

Symptoms of cancer appear relatively late, when the tumor reaches a significant size and disrupts the function of the organ in which it grows. If the organ is hollow, its patency may be disturbed, there are pathological (inflammatory or other) discharge, bleeding is possible. The patient feels weak, loses weight, his body temperature rises, he feels pain, the rate of sedimentation of red blood cells increases.

The most important principle of cancer diagnosis is its timeliness, detection of the tumor at an early (preclinical) stage, when recovery occurs in 80-95% of patients. For this purpose, all known modern medicine methods are used: clinical, biochemical, immunological, radiological, ultrasound, endoscopic, cytological, histological with a biopsy. The effectiveness of their combined application is very high.

Prevention of cancer — is, first, its detection at an early stage in the mass survey of the population, which is referred to the group of high risk. For this purpose, chest x-rays of lungs, mammography, PAP smear of the cervix, etc. Another problem prevention — create for people the optimal conditions for the existence of a minimizing contamination of the environment with a decrease in the probability of contact of the body with carcinogenic factors, the General health of the population. Such measures can significantly reduce the incidence of malignant tumors.

Cancer treatment — surgical, as well as with the use of hormones, radiation therapy and chemotherapy. To increase the body’s defenses resort to the effects on the immune system. Different methods of treatment are often used in combination with each other-depending on the stage of the disease, the location of the tumor, its tissue affiliation and other factors. There are many good clinics to treat this disease. In Russia^[ru], a good cancer center in Yekaterinburg, possible treatment in clinics in Germany, and others.

The incidence of cancer (epidemiology)

Cancer is a disease^[ru] of the  elderly. In the industrialized countries^[ru] of the West it ranks second after cardiovascular disease in the list of causes of death^[ru] and, despite the efforts of physicians, is not inferior to it for many decades in a row. There is even an increase in the incidence of cancer in these countries (from 1960 to 1980 — one and a half times), associated, as believed, with the aging of the population and the deterioration of environmental conditions in large cities. Six million dead (in 1996 — 6,3 million) — this is an annual tribute to the humanity of malignant tumors.

In some cases, the cancer recedes. Thus, the implementation of a social program to combat gastric cancer in Japan in a relatively short time led to a decrease in the incidence of almost twice. A significant reduction in the incidence of gastric cancer has also been observed in the United States^[ru] and Europe. However, it is connected with non-medical factors. The” culprit ” of the partial victory over the tumor was a household refrigerator, which radically changed the traditional methods of preservation of food products by salting and Smoking.

Different peoples and different geographical areas spread different forms of cancer. Japan and Russia are “sick” with stomach cancer. In the United States, developed countries of Europe, as well as in major cities of Russia, lung cancer and breast cancer predominate (in Moscow in 1996 from all forms of cancer died 225 thousand people). This is the result of pollution of the environment with industrial waste, exhaust gases of cars, tobacco Smoking, and also not always justified refusal of breastfeeding of newborns^[ru]. In Africa, the national disaster — liver cancer (small protein food), in Mongolia and Kazakhstan — esophageal cancer (scalding hot and fatty foods), in India and Central Asia — oral cancer (the habit of chewing betel). Americans ‘ addiction to easily digestible fiber-free foods (“fast food”) has led to growth in the country of colon and rectum cancer.

The change of place of residence is accompanied by a gradual decrease (in a generation) in the incidence of “native” cancer and the acquisition of a predisposition to cancer prevailing in the new country of residence. The prevalence of various forms of cancer is studied by analyzing the living conditions, habits and eating habits of the population, the mineral composition of the soil and water, the entire set of environmental conditions; special maps are compiled that reflect the number of diseases of various forms of cancer in specific settlements of a certain region.

The science of cancer is called — Oncology (from the Greek onkos — tumor and logos — word, doctrine) — medical and biological science, studying the theoretical, experimental and clinical aspects of oncogenesis in humans, animals, plants and developing methods of recognition, treatment and prevention of tumors.

Oncology was formed in the 20th century on the basis of the achievements of experimental medicine. In the experimental (starting with the works of Russian scientist Mstislav Alexandrovich Novinsky, 1876) and theoretical Oncology has developed 3 main areas: viral (French scientist Amadeus Borrell, 1903; American the pathologist and oncologist — Francis Rous, 1911), chemical (Japanese scientists, K. Yamagiwa and K. Ichikawa, 1915) and radiation (the French scientist and radiologist Antoine Lacassagne, 1932, and others) depending on the inducing agent. In the USSR^[ru], Lev A. silber, a scientist, microbiologist and immunologist, created the viral genetic theory of tumors. The rapid development of clinical Oncology is associated with the achievements of surgery, radiology, chemotherapy and immunology.

There are 2 forms of ophthalmia: newborns and adults. Infection in most cases, neonatal ophthalmia occurs during the passage of the fetal head through the birth canal of the mother with gonorrhea. O. appears on 2 – 3rd day of life and is characterized by a very strong first edema of both eyelids after 2 – 3 days begins copious pus. In severe cases, the process may be involved in the cornea, formed ulcer healing scar and leave a thorn. In some cases, the disease leads to blindness.

Sometimes occurs in newborns like illness Infections caused by a virus. It develops, in contrast to O., not before the 5th day of life and flows more slowly and less severely, the cornea in the process is never involved.

Infection ophthalmia adults occurs when entering the eye^[ru] with gonococcal urogenital hands, household items by patients suffering from gonorrhea. O. in adults is more severe than in infants, usually affected only one eye.

Treatment: frequent eye wash with a weak solution of potassium permanganate, antibiotics.

Prevention: the fight against gonorrhea urogenital tract. Newborn immediately after birth for ever let in both eyes, one drop of a 2% solution of silver nitrate or penicillin for adults – good personal hygiene. When a unilateral process is very important to prevent other eye disease ^[ru], for which the healthy ^[ru] eye pressure garment to wear a watch glass.

The most important general symptoms of anemia – fatigue, pale skin, shortness of breath, dizziness, tendency to faint. A. caused by three main factors: blood loss, impaired hematopoiesis, and increased kroverazrushenie.

A. associated with acute blood loss develops with wounds, gastrointestinal, pulmonary, nasal, uterine, less renal hemorrhage. A. At this suddenly appear sharp pallor, dizziness, tinnitus, thirst. It will not be life-threatening conditions, one should immediately stop bleeding that often requires surgical intervention, use styptics, blood transfusions.

A common cause of anemia – deficiency in iron, so iron is called A. Iron is part of hemoglobin and red blood cell enzymes involved in cellular respiration and is almost out of the body. Iron deficiency is caused by a small, but frequent blood loss (heavy and prolonged menstrual periods, bleeding hemorrhoids, etc.). A. very often this develops, if chronic blood loss combined with reduced secretion of gastric juice, which can reduce the absorption of iron in food. A. iron deficiency often occurs in children in the first year if the mother lacked the iron in the body. A. the same form is sometimes found in premature infants who did not manage to obtain the necessary amount of iron from the mother. A. iron deficiency may develop during puberty in girls born to mothers with iron deficiency in the body – juvenile chlorosis (“chlorosis” greensickness). For chlorosis, in addition to general attributes, A., characteristic hair loss, brittle nails, taste perversion (the desire to eat chalk, tooth powder, coal, slate from pencils), micturition disorders (bed wetting, frequent urge to urinate). Treatments for iron A. conduct various preparations of iron in combination with ascorbic acid (in this combination are better absorbed).

There are forms of anemia in which the body enough iron, but it is not fully used for the formation of hemoglobin due to the decreased activity of enzymes that form hemoglobin (sideroahresticheskaya A.). A. These are hereditary or associated with lead poisoning. When these forms of A. has a curative effect vitamin B6. Treats lead poisoning. Violation of blood formation is observed with a deficiency of vitamin B₁₂ (vitamin deficiency B₁₂, anemia Addison – Biermer, old name – A pernicious, pernicious anemia). A. the reason for this – a violation of the stomach making a special protein – gastromukoproteina (biermerin) providing intestinal absorption of vitamin B₁₂. A lack of vitamin B₁₂ in the body may be in patients who in the past has been removed the entire stomach, and also in patients with parasitic infestations, particularly broad tapeworm. When B₁₂ vitamin deficiency in the body is disturbed formation of ribonucleic acid (RNA) needed for cell reproduction. As a result of broken blood, red blood cells increase in size, their number in blood volume decreases. Due to the increase of the epithelial cells of the epithelium changes the structure of language, what is connected with his pain, and sometimes the spinal cord is affected. In 1926 he was invited to this form of anemia raw liver, from which was subsequently isolated vitamin B₁₂ – the main remedy for anemia Addison-Biermer.

Hemodyscrasia, expressed in the perversion of education in the bone marrow progenitor cells that form red blood cells, white blood cells and platelets, leading to the development of hypoplastic and aplastic A. For hypoplastic A characteristic decrease in the number per unit volume of blood red cells, white cells and platelets. In this form of anemia have a therapeutic effect hormones (glucocorticoid and male sex hormones), sometimes – removal of the spleen. Also used bone marrow transplantation.

Hemolytic anemia caused by increased hemolysis (destruction of red blood cells). Usually red blood cells live about 120 days. When the patient’s own antibodies against erythrocyte lifespan of red blood cells is much shorter. There is a rapid destruction of a large number of red blood cells due to the decaying of hemoglobin in patients are icteric staining tissues (jaundice). Developing immune hemolytic A., which is used to treat hormonal drugs (glucocorticoid hormones). Sometimes the birth of the child develops an acute hemolytic A., due to incompatibility of blood between mother and child (hemolytic disease of the newborn). Of hemolytic A. significant place hereditary forms. Their development is associated with a genetic dysfunction of enzymes involved in the formation of red blood cell membranes, or the accumulation of the energy necessary for their livelihoods and conservation of the shell.

In hereditary hemolytic anemia treatment effect sometimes makes removal of the spleen. In hereditary deficiency in the erythrocytes of certain enzymes (dehydrogenase, glucose-6-phosphate, etc.) lose their ability to counteract the harmful effects on vital cell processes of individual drugs, certain foods and other substances. In these patients, after administration of even small doses of acetylsalicylic acid (aspirin), streptotsida, quinine, by eating certain legumes and even if swallowed pollen of these plants have severe hemolytic A., which is more common in people living in Africa, of the Mediterranean basin, and in the CIS countries – in the southern republics.

In those geographic areas are common hereditary anemia associated with violation of the synthesis of the protein hemoglobin. A. These forms are called hemoglobinopathies. Red blood cells in some forms of the disease have sickle-shaped (crescent A.), sometimes – the target (mishenevidnokletochnaya A.).

Treatment of all types of anemia can be conducted only after a precise diagnosis and form A.).

The development of a common understanding of disease changed over the history of medicine. The ancient Greek physician and reformer of ancient medicine Hippocrates cause of the disease is considered misuse of mixing four basic body fluids: blood, phlegm, yellow and black bile (venous blood). Around the same time, based on the atomistic theory of ancient Greek materialist philosopher Democritus, the idea arose that the disease develops as a result of changes in the shape of atoms and their incorrect arrangement. At the end of the old and the beginning of a new era, and especially in the Middle Ages, idealistic views on the doctrine of the disease, according to which the soul or a special kind of life force (“Archean”), defines the struggle of the body to changes caused by boleznfmi.

Materialistic views on the disease in the Middle Ages developed by Ibn Sina (occurrence of the disease under the influence of invisible beings, the role of the constitution of the body). In the 17th – 19th centuries, a great contribution to the study of the disease have an Italian physician and anatomist Giovanni Battista Morgagni (the thought of illness due to anatomical changes in the organs), a French doctor, one of the founders of Pathological Anatomy and Histology, Marie Francois Xavier Bichat (description of the pathologic picture series diseases), the German pathologist Rudolf Virchow (theory of cellular pathology), C. Bernard (disease – a violation of physiological equilibrium with the environment) and other Russian therapist Sergei Petrovich Botkin, founder Viktor Pashutin Pathophysiology, Russian physiologist Ivan Petrovich Pavlov (Иван Петрович Павлов) and therapist Alexey Ostroumov disease associated with violation of the conditions of human existence and developed the idea of the disease on the basis of ideas nervism.

Despite the abundance of work on disease, the concept is still not precisely determined. Some authors deny the qualitative features of the disease as compared with health [ru]. Thus, the pathophysiology Alexander Bogomolets expressed the idea that the disease in the body does not produce anything really new. Others include the concept of a biological disease patterns. By PD Gorizontov’s disease is a common complex reaction that occurs as a result of violations of the relationship of the body and the environment. The disease is accompanied by the development of pathological processes from local manifestations of the general reaction of the body. In the writings of the Russian pathologist and founder of the scientific school of Hippolytus Vasilyevich Davydov upheld the provision that there is no fundamental difference between the physiology and pathology. Pathological processes and disease, in his opinion – it’s just a particular adaptive processes associated with subjective suffering. According to the concept of Canadian pathologist Hans Selye’s general adaptation syndrome, disease is stress (“stress”) that occurs in the body when exposed to extreme stimulus.

Causes of disease

Causes of disease are varied, but they can all be grouped under the mechanical, physical, chemical, biological, and for a man – and even psychogenic factors. Any of these factors is the state of the disease, if it is inadequate (ie, emergency, unusual) for the body. Inadequacy may be quantitative (amount of stimulus is excessive for the body), qualitative (the body is influenced by factors in relation to the quality of which is not produced in the body protective-adaptive mechanisms), temporary (quantitatively and qualitatively adequate stimulus affects long-term or at such intervals and in this rhythm, which are unusual for the body) and depending on the individual properties of the organism (ie, defined by individual reactivity of the organism in the form of increased sensitivity).

In today’s presentation of the disease is characterized by the following main features:

• 1. In the development of the disease plays a major role the external environment, and for the people – primarily social. Changes in the intrinsic properties of the body caused by environmental factors and firmly fixed (including and hereditary mechanisms), hereinafter themselves can play a leading role in the development of disease (see Medical Genetics).
• 2. Important in the development of disease than the etiological factor (that is, the causes of the disease) and external conditions are protective and adaptive mechanisms of the body. Development of diseases largely depends on the perfection of these mechanisms, the volume and speed of their inclusion in the disease process. The man on the development and course of disease is greatly influenced by psychogenic factors.
• 3. Disease – the suffering of the whole organism. There is a completely isolated diseased organs and tissues, as the local disease. With any disease to a greater or lesser extent, involved the entire body, which does not exclude the presence of the primary lesion in a particular organ or body part.

Distinguish the following periods of the disease: hidden, or latent (for infectious diseases – the incubation), – the period between the beginning of the impact of the pathogenic agent and the appearance of the first symptoms. It can last from a few seconds (for example, in cases of poisoning by strong poisons) to decades (eg, leprosy).

Prodromal period – the period of the first signs of the disease, which may be indefinite nonspecific (fever, fatigue, malaise), or in some cases, be representative of the disease (eg, stains Filatov – Koplik with measles). The period of full development of the disease, the duration of which varies from several days to dozens of years (tuberculosis, syphilis, leprosy).

Completion period of disease (recovery, convalescence) can occur quickly or gradually critically, analytically. Depending on the duration of the course and speed of the rise and disappearance of symptoms of diseases are acute and chronic joining the main manifestations of the disease additional changes not related to the immediate cause of the disease, but developing as a result of its flow is called a complication. It can occur in the midst of sickness and minovanii main manifestations. Complications aggravate illness, and sometimes can become a cause of adverse outcome. Outcome of the disease may include: complete recovery, recovery with residual or persistent change in organs, sometimes the emergence of new forms of the disease in the form of long-term effects, and death. Death as the end of the disease may occur suddenly, after a brief agony or gradually, through a more or less prolonged agonal state.

Classification of human diseases carried by the nature of the flow (acute and chronic diseases), and the level at which the body identifies specific pathological changes in disease (molecular, chromosomal, cellular and tissue, organ, disease of the whole organism), and etiological factor (disease caused by mechanical, physical, chemical, biological or psychogenic factors), and the method of treatment (medical, surgical, etc.), by age or gender differences (women, children), etc.

The most accepted is the nosological principle, that is, a classification of the disease, which is based on the grouping of diseases on related grounds. It should be noted that none of the existing classifications of disease is not fully satisfactory. Thus, when classification nosological principle pneumonia, for example, can be attributed to diseases of the respiratory system, to infectious diseases and allergic conditions. Therefore the creation of the modern classification of the disease is the most important task of theoretical and practical medicine.