What is mesothelioma?
Mesothelioma is a rare, slow-growing type of tumour of soft tissue. The tumour occurs mainly in men of advanced age and usually forms in the pleura. More rarely, the tumour can also be diagnosed in the peritoneum.
How does mesothelioma develop?
A mesothelioma forms from the thin layer of tissue called the mesothelium. The mesothelium is a two-layer membrane that covers the internal organs. There is fluid between the two layers of the mesothelium. This fluid allows the organs to slide past each other without any problems if they start to move. Mesothelioma most often forms in the lungs, but also in the chest wall. More rarely, mesothelioma occurs in the abdominal wall, the pericardium or the scrotum.
What causes mesothelioma to form?
Asbestos fibres are the most important risk factor for the development of mesothelioma. Inhaling asbestos fibres is particularly dangerous. Although the processing of asbestos has been banned in Germany since 1993 and now also in the entire European Union, the latency period is between 30 and 50 years. Above all, therefore, people who were employed in the construction industry fall ill with mesothelioma. In 2020 alone, 824 astbest-related mesotheliomas were recognised by the employers' liability insurance associations. Women come into contact with asbestos indirectly, for example through washing contaminated work clothes. If private demolition and/or renovation work has been carried out , there is also the possibility of coming into contact with asbestos fibres here .
In some cases, glass fibre dust or toxicosis, triggered by cigarette smoke or other exogenous pollutants, can also cause mesothelioma. More rarely, mesothelioma has occurred after radiotherapy due to treatment for Hodgkin's lymphoma or other malignant cancers.
What forms can mesothelioma be divided into?
A mesothelioma can be benign or malignant. While a benign mesothelioma is non-invasive and grows slowly, a malignant mesothelioma is characterised by its invasive and rapid growth. About 10 to 30 percent of all mesotheliomas are malignant.
Mesotheliomas can be further differentiated according to their locations as follows:
- Pleuromesothelioma: arises in the pleura and is the most common form of mesothelioma,
- in the pericardium,
- in the peritoneum, which occurs in 5 to 17 per cent of all cases,
- in the tunica vaginalis testis (skin surrounding the testicle)
What are the symptoms of mesothelioma?
Mesothelioma can cause the following symptoms, which usually only appear after a certain period of illness:
- recurrent accumulation of fluid in the chest cavity (pleural effusions),
- recurrent accumulation of fluid between the pericardium and the pericardial sac (pericardial effusions),
- recurrent abdominal fluid (peritoneal effusions),
- Shortness of breath due to the accumulation of fluid in the lungs,
- a swollen abdomen,
- Chest wall pain,
- Cough,
- Fatigue,
- Weight loss.
How is mesothelioma diagnosed?
A mesothelioma is usually difficult to diagnose. If mesothelioma is suspected , a histological examination is often carried out. This involves taking tissue samples to examine them under the microscope. The safest way to do this is to use thoracoscopy. Using the so-called "keyhole technique", a camera is inserted into the chest cavity in a minimally invasive procedure to remove pieces of tissue from the pleura using forceps.
In addition, the usual imaging examination procedures, such as an X-ray or a computer tomography (CT) scan, are used. Asbestos fibres can often be detected in the X-ray or in the tissue samples taken from the patient, which confirms the suspicion of mesothelioma.
As a rule, mesothelioma is only diagnosed at an advanced tumour stage. This is mainly because the disease is symptom-free for a long time.
How is mesothelioma treated?
The type of therapy depends on how far the mesothelioma has already spread. If possible, mesothelioma should always be removed surgically . Following the operation, radiation and/or chemotherapy is recommended, as the mesothelioma tissue preferably grows into the surgical canal.
In case of surgery, the following approaches are possible:
- (E)PD: (extended) plerectomy/decortication,
- P/D: Pleurectomy/Decortication,
- EPP: Extrapleural pleuropneumonectomy
The
first two procedures are aimed at removing the entire tumour
(complete resection) and, if possible, preserving the lung
. However, the latter is usually only possible in an early tumour stage
. If the tumour has already spread infiltratively,
usually only a complete macroscopic resection is possible (EEP).
If, on the other hand, the patient has impaired cardiac or lung function, a rather weakened general condition and
relevant concomitant diseases, P/D is the most suitable
surgical method. Particularly at an early stage of the disease,
lung function can still be preserved.
In any case, the focus when choosing the respective therapy is on keeping the patient's quality of life as high as possible. For example, removing fluid from the lungs can make it easier to breathe, or administering analgesics can relieve the patient's pain.
What is the prognosis for mesothelioma?
Mesothelioma has a rather unfavourable prognosis. The 5-year survival rate is 11 percent in men and 12 percent in women. The exact prognosis depends on whether the tumour is malignant and on the cell type. Generally, a distinction is made between three cell types:
- the epithelioid type,
- the biphasic type,
- the sarcomatoid type
The
epithelioid type has a better prognosis than the other two types
. In the best case, this means several years of life.