To understand what an epithelial tumor is and what it happens, you need to figure out what a neoplasm is and whether it is an oncology. It is very important. For example, oral epithelial tumors can be benign or malignant.
Unfortunately, today the number of people with cancer is growing, and mortality from this disease ranks third after deaths from diseases of the cardiovascular and respiratory systems. Approximately six million new cases of the disease are registered each year. Among men, the leaders were those citizens who live in France. And among women, representatives of the weaker sex living in Brazil are more likely to get sick.
The increase in the incidence can be partly explained by the aging of the inhabitants of the planet, as people of mature and especially old age suffer more often. According to statistics, every second cancer patient is a person over 60.
What is cancer and what are tumors of the epithelialorigin? What is the difference between benign and malignant neoplasms and what are they?
What is cancer
The term "cancer" is used in medicine as a general term for oncological diseases. It is characterized by uncontrolled cell proliferation. Their aggressive growth affects both the organ itself, from where the "wrong" cells originate, and nearby organs. Also, the malignant form of the tumor has a tendency to metastasize.
In men, the prostate gland and lungs are most often affected, and in women, the vulnerable organ is the mammary gland, a little less often the ovaries. By the way, epithelial ovarian tumors in 80-90% of cases develop from epithelial tissue.
How he althy cells "turn" into cancer cells
The human body is made up of billions of cells, all of which appear, divide and die at some point if they are he althy. All this is programmed, there is a beginning of the cell life cycle and an end. When they are normal, division occurs in appropriate quantities, new cells replace the old ones. The process does not go beyond organs and tissues. Regulatory systems of the body are responsible for this.
But if the structure of cells changes due to the influence of various factors, then they lose the ability to self-destruct, cease to control their growth, developing into cancer cells, and begin to multiply uncontrollably. That is, invasive growth is characteristic of such cells.
The result of this are"modified cells" that are capable of long life. They eventually form a malignant tumor. Cancer can affect up to several organs at once. Unhe althy cells spread throughout the body through the lymphatic and circulatory systems, spreading metastases.
Causes of cancer
The causes of oncology are varied, but experts cannot unequivocally answer the question of what exactly caused cancer in each individual case. Some believe that this is ecology, others blame it on genetically modified foods. At the same time, all scientists identify factors that contribute to disruption of cell function, which ultimately can lead to a malignant form of neoplasm.
There are a sufficient number of factors that influence the launch of carcinogenesis. What can contribute to the disease?
- Chemical carcinogens. This category includes vinyl chloride, metals, plastic, asbestos. Their peculiarity is that they are able to influence DNA cells, provoking malignant degeneration.
- Carcinogens of a physical nature. These include various types of radiation. Ultraviolet, X-ray, neutron, proton radiation.
- Biological factors of carcinogenesis - different types of viruses, such as Epstein-Barr virus, which causes Burkitt's lymphoma. The human papillomavirus can cause cervical cancer. Hepatitis B and C viruses contribute to liver cancer.
- Hormonalfactors - human hormones, such as sex hormones. They can affect the malignant degeneration of tissue.
- Genetic factors also influence the occurrence of cancer. If previous relatives had cases of the disease, then the possibility of developing the disease in the next generation is higher.
Names of benign and malignant tumors
The ending "ohm" is always present in the name of the tumor, and the first part is the name of the involved tissue. For example, a bone tumor is an osteoma, a adipose tissue tumor is a lipoma, a vascular tumor is an angioma, and a glandular tumor is an adenoma.
Sarcoma is a malignant form of the mesenchyme. The diagnosis depends on the type of mesenchymal tissue, such as osteosarcoma, myosarcoma, angiosarcoma, fibrosarcoma, and so on.
Cancer or carcinoma is the name of a malignant epithelial tumor.
Classification of all neoplasms
The international classification of neoplasms is based on the pathogenetic principle, taking into account the morphological structure, type of cells, tissues, organs, locations, as well as the structure in individual organs. For example, organ-specific or organ-non-specific.
All existing neoplasms are divided into seven groups. The group depends on the belonging of the tumor to a particular tissue and distinguishes them by histogenesis.
- epithelial tumors without specific localization;
- tumors of exo- or endocrine glands or specific epithelial tissues;
- soft tissue tumors;
- tumors of melanin-forming tissue;
- tumorsbrain and nervous system;
- hemoblastoma;
- teratomas, dysembryonic tumors.
Medicine separates two forms - benign and malignant.
Epithelial benign and malignant tumors
Clinically divided:
- benign forms of epithelium or epitheliomas;
- malignant, which is called cancer or carcinoma.
According to histology (type of epithelium) they are distinguished:
- neoplasm from the integumentary epithelium (stratified squamous and transitional);
- from glandular epithelium.
By organ specificity:
- organ-specific tumors,
- organo-nonspecific (no specific localization).
Benign form
Benign epithelial tumors (epitheliomas) include:
- Papilloma (from squamous and transitional integumentary epithelium).
- Adenoma (from glandular epithelium). In a malignant form, it is a carcinoma.
Both varieties have exclusively tissue atypia and have parenchyma and stroma. The well-known papillomas are a benign form of an epithelial tumor, which, in turn, comes from the tissue of the integumentary epithelium.
Papillomas are formed on the surface of the skin from squamous or transitional epithelium. They may also not be on the surface, but, for example, in the mucous membrane of the pharynx, on the vocal cords, on the tissues of the bladder, ureters and renal pelvisor elsewhere.
Outwardly, they resemble papillae, and can also resemble cauliflower. They may be single, or they may be multiple. Papilloma often has a stalk that is attached to the skin. Tissue atypism occurs as a result of a violation of the main feature of any epithelium - complexity. With such a violation, a failure occurs in a certain arrangement of cells and their polarity. With this benign tumor, expansive cell growth (basement membrane) is preserved. With expansive cell growth, the neoplasm grows out of itself, increasing in size. It does not intrude into neighboring tissues, which would lead to their destruction, as with invasive growth.
The course of papillomas is different and depends on the type of affected tissue. Papillomas located on the surface of the skin (or warts) develop and grow slowly. Such formations, as a rule, do not cause much concern to their owners. But in case of appearance in the internal parts of the body, they cause enough problems. For example, after removal of papillomas from the vocal cords, they may reappear, as they are recurrent in nature. Benign papillomas of the bladder can begin to ulcerate, which subsequently leads to bleeding and hematuria (blood appears in the urine).
Despite the fact that papillomatous neoplasms on the skin are a benign form of a tumor and do not cause much concern, malignancy of a tumor into a malignant one is still possible. This is facilitated by the type of HPV and predisposing external factors. There is more600 types of HPV strains, of which more than sixty have an increased oncogene.
Adenoma also refers to a tumor of epithelial origin and is formed from the glandular epithelium. This is a mature neoplasm. The mammary gland, thyroid and others are a possible location for adenoma dislocation. It can also form in the mucous membranes of the stomach, intestines, bronchi and uterus.
The growth of adenoma cells, as well as in papillomas, has an expansive growth pattern. It is delimited from the adjacent tissue and looks like a knot of soft-elastic consistency, pinkish-white in color.
To date, the principle of development of this formation is not fully understood, but usually it is possible to see the first disturbances in the balance of hormones - regulators of the function of the glandular epithelium.
In cases where a cyst is present in such a benign neoplasm, the term cysto- or cystoadenoma is used.
By morphological types, adenomas are divided into:
- fibroadenoma - an adenoma in which the stroma prevails over the parenchyma (often formed in the mammary gland);
- alveolar or acinar, which copies the terminal sections of the glands;
- tubular, capable of maintaining the ductal character of epithelial structures;
- trabecular, which is characterized by a beam structure;
- adenomatous (glandular) polyp;
- cystic with a pronounced expansion of the lumen of the glands and the formation of cavities (this is just a cystoadenoma);
- Keratoacanthoma refers to an e-cellular tumor of the skin.
Feature of adenomais that they are able to degenerate into cancer, into adenocarcinoma.
Malignant form
This type of cancer can develop from the integumentary or glandular epithelium. Epithelial cancer can appear in any organ where epithelial tissue is present. This type is the most common among malignant forms of tumors. It has all the properties of malignancy.
All malignant neoplasms are preceded by precancerous conditions. At some point, cells acquire cellular atypism, anaplasia begins, and they begin to constantly multiply. Initially, the process does not go beyond the epithelial layer and there is no invasive cell growth. This is the initial form of cancer for which experts use the term "cancer in situ".
If pre-invasive cancer is recognized during this period, it will help to get rid of further serious problems. As a rule, surgical treatment is performed, and in this case, a favorable prognosis is outlined. The problem is that the patient rarely experiences any symptoms of the disease, and this "initial" cancer is difficult to detect, as it does not show up at the macroscopic level.
A malignant tumor from epithelial tissue according to histogenesis can have the following character:
- transitional cell from integumentary epithelium (squamous and transitional);
- basal cell;
- undifferentiated cancer (small cell, polymorphocellular, etc.);
- basal cell;
- keratinizing squamous cell carcinoma (malignant formsdiseases of the epithelial structure are most often (up to 95%) represented by keratinizing squamous cell carcinoma;
- squamous cell nonkeratinizing cancer.
A separate category is mixed forms of cancer. They consist of two types of epithelium - flat and cylindrical. This type is called "dimorphic cancer".
Cancer originating from glandular epithelium:
- Colloid and its variety - ring cell carcinoma.
- Adenocarcinoma. By the way, the name of this tumor was given by Hippocrates. He compared her appearance to a crab.
- Solid cancer.
Also, experts distinguish the following tumors from epithelial tissue according to their features:
- medullary, or medulla, cancer;
- simple cancer, or vulgar;
- skirr, or fibrous cancer.
Symptoms of cancer
Symptoms of the disease depend on where exactly the tumor developed, in which organ, on the rate of its growth, as well as the presence of metastases.
Common signs:
- Change in the condition of the skin in a certain area in the form of a growing swelling, which is surrounded by a border of hyperemia. Swellings may begin to ulcerate, ulcers appear that are difficult to treat.
- Change in the timbre of the voice, it is difficult for a person to swallow, coughing attacks, pain in the chest or abdomen.
- The patient may lose a lot of weight, he is characterized by poor appetite, weakness, persistent fever, anemia, induration in the mammary gland and bloody discharge from the nipple or bladder,difficulty urinating.
But other symptoms may be present.
Cancer diagnosis
You need a timely trip to a specialist for a thorough examination and a detailed collection of tests. Diagnostic methods for identifying the disease include:
- physical method of studying the patient;
- computed tomography, MRI (considered a very effective method), radiography;
- blood test (general and biochemical), detection of tumor markers in the blood;
- puncture, biopsy with morphological examination;
- bronchoscopy, esophagogastroduodenoscopy.
All these measures will help to detect the disease at an early stage and fully cure the patient.
