Types of cancer

What you need to know about cancer

The term cancer in the majority of the population in everyday life is associated with the entire spectrum of malignant tumors that cause various cancers. In the human body, it can develop from epithelial cells of any organs and tissues. Basically, cancer is a general term for a large group of oncological diseases in tissues and organs. Despite the significant progress of medicine, oncological diseases confidently rank second in the world after cardiovascular diseases. They tend to grow and are one of the reasons for high mortality. The situation is similar in Ukraine, where there are more than a million cancer patients, and the annual increase is about 130-150 thousand people. According to WHO forecasts, by 2032 the number of new cancer cases in the world will increase by almost 70%. This makes this medical and social problem extremely relevant both for society as a whole and for each of its citizens.

The mechanism of carcinogenesis is based on a violation of the control over the multi-stage process of division, growth and specialization of cells (mutations of the cell genome). This leads to their uncontrolled division, growth, change in morphology and function, and eventually to degeneration (malignancy) with the acquisition of uncharacteristic properties. The "malignancy" of the process is due to:

• uncontrolled growth and proliferation of cells;
• with the ability to germinate (infiltrate) into nearby tissues/organs;
• the possibility of tumor cell migration to nearby and distant organs through the blood/lymphatic system with the formation of metastases.

Mostly, cancer is a cancerous tumor, but oncological processes can also occur in the liquid environment of the body (in blood and lymph). Mutation of the genome of cells, according to modern medicine, can occur under the influence of a number of factors, the main of which include:

• Heredity (genetic predisposition) - statistically significantly increases the risk of developing certain types of cancer.
• Influence of a wide range of physical and chemical carcinogenic factors. Among them are ultraviolet (solar) exposure, radiation, electromagnetic action, tobacco smoke, aromatic hydrocarbons, aldehydes and polyphenols, metals (chromium, zinc, asbestos, lead, arsenic), polymers.
• The presence in the diet of "harmful" products, which contain various types of dyes, GMOs, synthetic preservatives, stabilizers.
• Abuse of alcoholic beverages.
• Biological agents (oncoviruses). Among them are papilloma virus, herpes virus, adenoviruses, hepatitis B and C viruses.
• Immunodeficiency conditions.
• Metabolic disorders and hormonal imbalance.
• Frequent psychotraumas (stress, depressive states).
• Minimum mobility.

Ontogenetic (age) mutations occur in the body almost constantly, but they are under the control of protective systems until the moment when the entire "ecosystem" of the body is disturbed. Then there are favorable conditions for the development of a disease such as cancer.

Symptoms of cancer

When talking about cancer, most people use this term in the singular. In fact, it refers to completely different diseases that have their own symptoms and require individual approaches to treatment.

Oncology symptoms depend on many factors:

• type of cancer;
• location of the tumor;
• the stage at which the disease is located;
• speed with which education develops;
• presence or absence of metastases.

The first signs of cancer are non-specific and are manifested by general weakness, a sharp decrease in body weight, low-grade fever, lack of appetite.

Specific signs depend primarily on the organ affected by the tumor:

• With lung carcinoma, the first manifestation of cancer is a cough, hoarse voice, chest pain, shortness of breath.
• Symptoms of a malignant tumor that has arisen in the mammary gland - painless thickening, enlargement of regional lymph nodes, discharge of fluid from the nipples.
• Some types of disease, such as prostate cancer, are almost asymptomatic in the initial stages. As the tumor grows, there is pain, traces of blood in the urine, and problems with urination.
• Tumors of the gastrointestinal tract have an extremely wide range of symptoms, it all depends on the affected organ. Abdominal discomfort, bloating and pain, nausea/vomiting, defecation disorders, increased fatigue and weakness may be common.

Stages of cancer

Determining the stage of a cancer tumor is the most important condition:

• diagnosis of cancer;
• understanding the level of prevalence of the tumor and its localization;
• selection of patient treatment methods;
• evaluations of therapy results;
• prognosis of survival and control of the effectiveness of the treatment process.

Currently, the TNM classification, which takes into account 3 components, is generally recognized:

• T — determines the spread of the neoplasm, its size, germination in the surrounding tissues (T0 — T4).
• N — informs about the presence of metastases in the lymph nodes (N0 — N3).
• M means the presence of metastases in various organs (M0 - M1).

On the basis of tumor classification according to TNM, diagnosis of the stage of cancer in general is carried out. However, for each localization of the tumor, there are additional requirements for examining the patient and determining specific parameters.

Stage 0. ("Cancer in place"). Does not go beyond the epithelium, the tumor is located in the place of education.

Stage I. The borders are extended within the tissue of the affected organ, the tumor does not penetrate into the adjacent lymph nodes/tissues.

Stage II - III. The tumor has penetrated deep into the tissues and regional lymph nodes, but other parts of the body have not yet been affected.

Stage IV. Terminal stage with organ damage. Metastases appear in distant organs, distant lymph nodes are affected.

Approximate survival of patients at one or another stage of the disease is estimated based on reliable data from statistical studies. Statistical data allow to estimate the overall/relative median survival and the average duration of remission. Oncologists never get tired of repeating that if cancer is detected in the early stages, it is often curable.

Types and types of cancer

Malignant neoplasms are classified according to various characteristics, one of which is the localization of the primary tumor. In this regard, cancer of the specific organ in which the tumor was diagnosed is distinguished, for example:

• kidney cancer;
• bladder/gallbladder cancer;
• esophagus cancer;
• thyroid cancer;
• blood cancer (leukemia);
• liver cancer;
• throat cancer, etc.

The prevalence of each of the diseases varies significantly depending on the country, gender, and age. In men, the structure of cancer incidence (in %) looks as follows:

• lung cancer - 25.2%;
• stomach - 14.1%;
• skin - melanoma, Kaposi's sarcoma - 7.9%;
• prostates - 6.1%;
• rectum - 4.9%.

In women, the prevalence is completely different:

• breast cancer - 18.2%;
• skins - 12.9%;
• cervix - 9.9%;
• intestines - 5.2%;
• ovary - 1.8%.

Diseases such as cancer are much less common:

• brain;
• languages;
• testicles;
• bones;
• anus;
• lips;
• penis;
• disease of lymphoid tissue - lymphogranulomatosis.

Cancer treatment

In the treatment of a cancerous tumor, a combination of various methods is used, which allows to achieve the maximum possible efficiency and increase the median survival of patients. Surgical intervention is the leading method of treatment of the vast majority of forms of malignant neoplasms. Its volume is determined by the stage of the cancer. In some cases, it is not just complete/partial removal of the tumor with surrounding tissues or metastases, but complete removal of the organ (uterus, ovaries, mammary gland). Such operations, despite the violation/exclusion of certain functions in the body, are among the most effective. Most often, they can become the only possible way out to save life.

In late stages of cancer (or early in inoperable patients), radiation therapy is widely used in oncology. It can precede surgical intervention, and be carried out after it, as well as be used in combination with chemotherapy and surgery. Modern methods of radiotherapy - SBRT, IGRT, IMRT, TomoTherapy HD system, proton beam therapy. They allow you to effectively affect any neoplasms in all parts of the body with:

• high accuracy;
• different dose loads;
• the possibility of simultaneous irradiation of several or extended targets without changing the patient's position.

There is another leading method of treatment of oncological diseases, especially in patients with an unresectable stage (it is technically impossible to remove the tumor). This is chemotherapy, which is used both as monotherapy and in combination with radiation therapy. In practice, a wide range of cytostatics is used, including platinum-based drugs with a relatively low toxic effect and good tolerability. The choice of the optimal regimen of chemotherapy for cancer and specific drugs is made taking into account the general condition of the patient. The functional reserves of his body and the cytotoxic effect of drugs are evaluated.

Modern approaches to chemotherapy in oncology involve the use of "targeted" drugs (Tartseva, bevacizumab, neovastat, bexarotene, trastuzumab, etc.). They act selectively on certain targets, the expression of which contributes to the stabilization of the tumor process. The mechanism of their action is based on the cytostatic effect, which contributes to the inhibition of tumor growth.

Other methods of treatment also find their application, in particular:

• hormone therapy (for cancer of the reproductive system);
• immunotherapy based on the introduction into the body of biologically active drugs with antitumor activity (monoclonal antibodies, T-helpers, cytokines, TIL cells).

Prevention of cancer diseases

Given the level of modern knowledge, including about the main risk factors for the development of cancer, a significant part of oncological diseases can be prevented. For this, first of all, high vigilance about cancer is necessary.

Cancer prevention should be carried out at different levels, including individually. First of all, it is:

1. minimization of the influence of carcinogenic factors - smoking, adverse environmental factors (working/living in a potentially dangerous area, contact with carcinogens);
2. normalization of lifestyle - fight against obesity, abuse of alcoholic beverages, hypodynamia, unhealthy diet, avoidance of stress;
3. competent contraception;
4. timely treatment of precancerous diseases;
5. limiting exposure to sunlight;
6. systematic examination of various organs and body systems.

In essence, cancer prevention is leading a healthy lifestyle. Balanced nutrition with a high content of natural products, in particular vegetables and fruits, is of great importance in oncology. Fatty and fried products, trans fats, fast food, sweets, products containing food additives (dyes, flavor enhancers, preservatives, nitrates) are subject to restriction.

The role of medical institutions in the secondary prevention of oncology is no less important. They ensure an increase in the level of awareness of the population in oncology, high-quality control of risk groups, diagnosis and timely treatment of benign tumors and precancerous conditions.

Given the special importance of detecting cancer in the first stages, if any negative symptoms associated with malignant diseases appear, you should immediately consult an oncologist. Timely treatment is the key to effective cancer treatment and can save your life.