Mesothelial cells line the inside of the chest and abdominal cavities, as well as the heart bag – the cavity around the heart. These cells also line the surfaces of most internal organs. The tissue formed by mesothelial cells is called mesothelium. The chest mesothelium is called pleura, the abdominal cavity is called the peritoneum, and the heart cavity is called the pericardium. Mesothelial tumors are benign and malignant, with malignant tumors called mesotheliomas usually occur. Mesothelioma is a rare tumor that is more common in men after 50 years. Every year, 2-3 thousand new cases of the disease are detected. The tumor can be asymptomatic for a long time and therefore is often detected in the late stages, which negatively affects the prognosis (outcome) of the disease. The average survival of patients is usually only 1-2 years.
DIFFERENT THREE TYPES OF MALIGNANT MESOTELIOMA:
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1. The epithelioid type, comprising 50-70%
among all mesotheliomas and having the best prognosis (outcome).
2. Sarcomatoid type (7-20%).
3. Mixed type (20-35%).
Almost 3/4 of mesotheliomas occur in the chest cavity and are called pleural mesotheliomas. In 10-20% of cases, a tumor develops in the abdomen – peritoneal mesothelioma. Pericardial mesothelioma is very rare.
RISK FACTORS FOR MALIGNANT MESOTHELIOMA
Contact with asbestos is a major risk factor for mesothelioma. Asbestos is used in the manufacture of insulating and refractory materials, tiles, brake pads, etc. After establishing the relationship between contact with asbestos and the development of mesothelioma, the use of this substance was sharply reduced. The risk of developing mesothelioma depends on the intensity and duration of contact with asbestos. Long-term contact at a young age significantly increases the risk of mesothelioma. The time period from the moment of the first contact with asbestos to the diagnosis of the tumor is 20-50 years. Smoking in itself does not affect the increase in the incidence of mesothelioma, but the combination of smoking and exposure to asbestos significantly increases the risk of developing lung cancer. In smokers with asbestos exposure, the risk of developing lung cancer is 50–90 times higher than in the general population. To prevent (prevent) the development of mesothelioma, it is necessary to avoid contact with asbestos at home and in the workplace.
DIAGNOSIS OF MESOTHELIOMA
The early symptoms of mesothelioma are not specific. They are often ignored by patients or taken for the manifestations of ordinary non-tumor diseases. In most patients with mesothelioma, symptoms appear 2–3 months before the tumor is detected.
some patients, symptoms may persist for 6 months or more.
50% of patients with pleural mesothelioma note
pain in the lower chest on the side or back surface. Many patients
complain of shortness of breath. In some cases, there is difficulty
swallowing, coughing, sweating, weakness, weight loss and fever. Other symptoms
include hoarseness, hemoptysis, and swelling of the face and upper limbs.
In patients with peritoneal mesothelioma,
abdominal pain, nausea, vomiting, weight loss are possible. Some patients
may develop fluid in the abdomen and / or a tumor. If you suspect a
mesothelioma, you must immediately consult a doctor who will find out the
presence of risk factors and schedule an examination. During the
examination, the doctor can detect the presence of fluid in the pleural cavity
(pleurisy), abdomen (ascites) or pericardium, which occurs as a result of the
development of the tumor.
X-ray of the chest allows you to detect thickening of the
pleura, the presence of calcifications (mineral deposits) in the pleura and
fluid in the pleural cavity.
Computed tomography (CT) makes it possible to diagnose
mesothelioma and determine the prevalence of the process (stage).
Magnetic resonance imaging (MRI) can help detect damage to the
diaphragm, the muscle tissue that separates the chest and abdominal cavities.
Thoracoscopy (examination of the pleural cavity using
a special apparatus) allows not only to identify the tumor, but also to make
a biopsy (take a piece of
tissue for examination) or get a liquid for microscopic examination to clarify
Laparoscopy (examination of the abdominal cavity
using the apparatus) allows you to examine the abdominal cavity, take a piece
of the tumor or fluid for examination.
STAGES OF MESOTHELIOMA
Currently, only the stages of pleural mesothelioma are distinguished, since it occurs much more often than other localizations.
4 stages of pleural mesothelioma
I – the tumor affects
the pleura on the left or on the right, while the lymph nodes are not involved
in the process.
II – a unilateral lesion
of the pleura and the spread of the tumor to the diaphragm or lung tissue.
III – a unilateral lesion
of the pleura and the spread of the process to the anterior chest wall, or to
the adipose tissue of the mediastinum, or pericardium, or lymph nodes on the
side of mesothelioma.
IV – Mesothelioma involves
muscles or ribs in the process, or the diaphragm, or esophagus, trachea,
thymus, large blood vessels, or spine grows, or passes to the other side, or
spreads through the bloodstream to distant organs.
The progression of the disease occurs slowly in time, but aggressively in the capture of surrounding tissues. Cells of growth sprout into neighboring tissues in the first stages, and in the third stage, multiple metastases are observed. The most accurate description of the stages exists only for pleural cancer.
At the first stage, the lining of the cavity is affected.
Further, the cancer affects the lung tissue with which it most
often comes in contact.
The formation affects the heart bag and mediastinum (tissues
located in the center of the sternum in front).
Cancer affects the intercostal muscles, surrounding organs and
Other mesotheliomas proceed according to a similar pattern,
spreading to surrounding tissues and giving metastases, starting from the third
All tumors of this type are divided into:
in which the cells adjoin each other not tightly, without forming a clear structure. A
tumor without smooth borders, resembles a thickening on the surface, can spread
to large areas. Cancer cells actively penetrate deeper layers of tissue
and grow into neighboring organs. Most of these tumors occur (75%).
strict boundaries. Reminiscent of a bright, bulging node, consisting of
cells similar to epithelial. Such an education is considered more benign,
since it does not give metastases and does not affect neighboring organs.
Depending on the structure of cells in the diffuse type of
mesothelioma, several subspecies are distinguished:
tumors. The most common (54% of all cases). Spread over the
surface of the mesothelium. Cells are similar in structure to epithelial
structures quickly grow into the internal connective tissues and are similar to
them in the appearance of the cells.
often formed in the abdominal cavity. Cancerous elements have a rounded
shape. Around the tumor, a dense connective tissue rim is formed.
(biphasic), consisting of cells of the first two groups. They are
found quite often – in 25% of patients.
There are very rare forms that today are almost never
diagnosed. This is papillary mesothelioma and an adenomatous
tumor. They are considered benign because they do not give metastases.
Mesothelioma Main symptoms
The tumor grows slowly, so the symptoms do not appear immediately. Sometimes, before the first clinical manifestations, three to five years pass. As a result, education is detected mainly in the later stages, which reduces survival. After diagnosis, life expectancy does not exceed two years.
As the first symptom, 70% of patients report pain. It is
dull in nature, it is difficult to determine the exact place of its
localization. Further in the affected area, fluid begins to
accumulate. This is due to the fact that all mesotheliomas are capable of
producing mucus. Weight loss and an increase in body temperature are
observed only in 30% of cancer patients.
The remaining symptoms
are more specific and depend on the location of the focus.
Pleural tumors are characterized by
cough, bloody sputum, swelling of the joints and thickening of the
fingers. As the disease develops, hoarseness of the voice appears,
squeezing of the vena cava, which disrupts blood circulation in the head and
neck. Accumulation of fluid causes shortness of breath. With a
tumor of the peritoneum, bloating, nausea, and upset stool appear. The abdomen
increases in size with the accumulation of mucous secretions. There is
swelling of the legs due to squeezing of blood vessels by an enlarged abdomen. The
defeat of the pericardium is initially limited
to pain and interruptions in heart activity, reminiscent of other heart
diseases. And after the accumulation of fluid, suffocation, significant
circulatory disorders can develop.
Diagnosis and treatment
The most common diagnostic methods are:
X-ray , which shows whether there is a thickening of the wall
and fluid in the cavity.
Computed tomography , which determines
how much the tumor has spread.
Thoracoscopy and laparoscopy with biopsy . At
the same time, an apparatus is introduced into a special incision, with the
help of which the doctor examines the diseased cavity from the inside and takes
the tissue for analysis.
Mesothelioma is easily confused with other diseases. Even
when symptoms become apparent, they are similar to inflammation of the lining
membranes, resemble manifestations of sarcoma, or are mistaken for metastases
from other tumors. Only the study of tissue samples can finally determine
the type of cancer. But even then, the correct diagnosis is made only in
80% of cases.
there are no effective treatments for mesothelioma.
Only 10% of patients undergo surgery, those who are diagnosed
with a localized tumor. In 60% of cases after resection, complications
appear, and for more than two years only 35% of the operated on live. Chemotherapy
gives temporary improvements and only for 48% of patients. For its
implementation, modern cytostatics are used – drugs that stop the division of
tumor cells and provoke their death. To reduce the activity of mucus
secretion by a tumor, cytostatics can be injected directly into the diseased
Irradiation is used to alleviate symptoms in order to improve
the quality of life of the cancer patient. Radiotherapy extends life by
approximately one year. The best results with a survival rate of 45% are given
by a combination of all three types of therapy, starting with surgery, followed
by six courses of chemotherapy and final exposure.
TREATMENT OF MALIGNANT MESOTHELIOMA
The choice of treatment tactics depends on a number of factors, including the stage of the tumor, the general condition of the patient and his opinion. Given the rarity of mesothelioma, it is advisable to conduct treatment in specialized oncological institutions with experience in treating such patients.
The operation can be performed both with palliative and therapeutic purposes. By palliative surgery is meant a surgical intervention that can eliminate or reduce the pain or discomfort caused by the growth of a tumor. Such operations are used when it is impossible to remove the tumor due to the prevalence of the process or the serious condition of the patient.
Pleuroectomy / decortication is, as a rule, a palliative operation
and consists in the removal of pleura, which prevents the accumulation of fluid
and reduces pain.
Thoracocentesis is a procedure in which fluid is removed
from the pleural cavity with a needle to alleviate the condition of the
The introduction of talcum powder
or an antibiotic into the pleural
cavity in order to temporarily prevent the accumulation of fluid in it is
effective in 90% of patients with pleural mesothelioma.
A puncture of the anterior
abdominal wall allows removal
of accumulated fluid in the abdomen in patients with peritoneal mesothelioma.
In patients with pericardial mesothelioma, performing
pericardial puncture makes
it possible to remove fluid and improve cardiac activity.
In patients in satisfactory condition, having a localized
tumor, radical surgery is performed , i.e. complete removal of mesothelioma.
It should be borne in mind that often after
the alleged radical operations there are microscopic foci of the tumor. In
this regard, the importance of radical operations in patients with mesothelioma
An extrapleural pneumonectomy is the removal of the pleura, diaphragm,
pericardium and lung on the affected side. Such an extended operation can
only be performed by highly qualified oncologist surgeons in patients with good
general condition without serious concomitant diseases.
In patients with localized mesothelial
peritoneum, an attempt can be made to remove the tumor along with part of the
abdominal wall. Unfortunately, in most patients with peritoneal
mesothelioma, radical surgery is not possible due to the prevalence of the
process. In the case of a localized lesion of the pericardium, its removal is
performed, and in a common process, palliative interventions that prevent the
accumulation of fluid.
External exposure is most often used in patients with mesothelioma.With internal exposure, the radioactive material is delivered directly to the tumor. This type of radiation therapy is used as the main method of treatment for patients in serious condition, when they cannot undergo a serious operation. Ancillary radiation therapy is prescribed after non-radical operations to destroy the remaining tumor cells. Palliative radiation is used to relieve symptoms caused by tumor growth: shortness of breath, pain, bleeding and difficulty swallowing.
Radiation therapy can cause adverse reactions
and complications in the form of skin burns, weakness, nausea, vomiting, loose
stools, damage to lung tissue, difficulty breathing. Most adverse reactions
occur after completion of the course of exposure. You should be aware that
radiation therapy can exacerbate the side effects of chemotherapy.
In the treatment of patients with malignant mesothelioma, chemotherapy can be administered not only intravenously, but also intrapleurally and intraperitoneally (into the abdominal cavity). Depending on the stage of the tumor, chemotherapy can be either the primary or secondary treatment. Moreover, chemotherapy is used only as a palliative, giving only a temporary effect. Of the antitumor drugs used: doxorubicin, cisplatin, methotrexate, vinorelbine, etc. in various combinations.
Adverse reactions to chemotherapy include:
nausea, vomiting, loss of appetite, baldness, the appearance of mouth ulcers,
increased susceptibility to infections, bleeding. Most adverse reactions
disappear after completion of treatment.
The most aggressive tumor with a poor prognosis is sarcomatoid
mesothelioma. For other types of formations, there are factors that are
considered unfavorable and, when they are identified, only 14% of patients step
over the annual line of survival. These factors include:
Decreased hemoglobin levels and a significant increase in white
The defeat of the lymph nodes.
Low index on the Karnowski scale – helps to determine the
condition of the patient, depending on the preservation of his mobility,
activity. The index is considered low if a person cannot serve himself and
spends half of the day in bed without strength.
If there are no such signs, then the prognosis improves, and the
patient survives in 42% of cases.