Mesothelioma and asbestosis are the two most well-known diseases caused by asbestos exposure. The background of both is asbestos fibers that have entered the lungs with the breath, but the diseases differ significantly in terms of mechanism, prognosis and treatment. In Finland, these diseases are still diagnosed every year, especially in people who were exposed to asbestos before the ban on its use in 1994.
Mesothelioma, a rare but aggressive cancer
Mesothelioma is a malignant tumor arising in the surface layer of the pleura or peritoneum. More than 80 percent of mesothelioma cases are related to previous exposure to asbestos. There have been particularly dangerous forms of asbestos crocidolite (blue asbestos) and amosite (brown asbestos), but also common chrysotile (white asbestos) can cause disease.
Mesothelioma is characterized by a long latency period, 20 to 50 years after exposure to the first symptoms. The most common symptoms are progressive shortness of breath, constant chest pain, weight loss and fluid accumulation in the pleura. Unfortunately, the prognosis is often poor, and the average survival time from diagnosis is 12 to 21 months, although new treatments have improved the situation.
Asbestosis, a lung scarring disease
Asbestosis is the slow connective tissue of the lung tissue, i.e. scarring, which occurs as a result of long-term and abundant exposure to asbestos. Unlike mesothelioma, asbestosis is dose response disease, i.e. its development usually requires years or decades of exposure to significant fiber concentrations.
Symptoms of asbestosis include progressive shortness of breath on exertion, a dry cough, crackling sounds in the lungs and a decrease in performance. The disease is not cured, but its progression can be slowed down by avoiding new exposure and treating associated diseases. Asbestosis also significantly increases the risk of lung cancer.
How are mesothelioma and asbestosis different?
Although both diseases are caused by asbestos, their natures are very different.
- Mesothelioma is a cancer that can arise from even short or moderate exposure
- Asbestosis is a connective tissue disease that usually requires a lot of exposure
- In mesothelioma, growth occurs in the pleura or peritoneum, in asbestosis in the lung tissue itself
- Asbestosis usually develops in 10 to 30 years, mesothelioma in 20 to 50 years
- Asbestosis can be stabilized, mesothelioma almost always progresses actively
Prevalence of diseases in Finland
According to the statistics of the Finnish Institute of Occupational Health, approximately 70-100 new cases of mesothelioma and several dozen new cases of asbestosis are found in Finland each year. The numbers have remained high because the exposures occurred mainly in the 1960s-1980s and the latency period is long. The peak numbers are expected to be seen at the end of the 2020s, after which the number of cases will start to decrease with the asbestos ban.
The diagnostic process
The diagnosis of both diseases is based on work history, clinical symptoms and imaging studies. The process typically goes like this:
- The occupational health doctor examines the exposure history in detail
- A lung HRCT scan is performed, which reveals scars, pleural plaques and tumors precisely
- Lung function is measured with spirometry and a diffusion test
- If mesothelioma is suspected, it is taken biopsy from the pleura for histological confirmation
- If necessary, a PET-CT scan is performed to assess the spread
Treatment options
There is no cure for asbestosis, but the symptoms can be alleviated with oxygen therapy, respiratory muscle exercises and quitting smoking. Regular monitoring and prompt treatment of respiratory infections are essential. Treatment options for mesothelioma depend on the spread and location of the cancer:
- Surgery, if the tumor is limited and the patient is otherwise in good health
- Chemotherapy, which is often the first line of treatment
- Radiation therapy to relieve symptoms
- Immunotherapy, which has improved the prognosis in recent years
- Palliative care in more advanced cases, to secure the quality of life
Occupational disease and compensation
Both mesothelioma and asbestosis are almost always recognized in Finland as an occupational disease, when occupational exposure can be demonstrated. Recognition of an occupational disease opens up the right to compensation paid by the accident insurance, coverage of treatment costs and possible damages. Kela and the occupational pension system also provide support when the ability to work is reduced. The notification of the occupational disease is made by the attending physician, and the process should be started immediately after the diagnosis.
The best treatment is prevention
Because mesothelioma and asbestosis are not completely cured, the most important measure is to prevent further exposures. In Finland, asbestos is still found in thousands of properties built before 1994, and renovation or removal work can release fibers into the breathing air. That's why asbestos survey before renovation is a statutory and vital safeguard. Read more about asbestos surveys and about the health risks of asbestos, get to know our survey service or order an asbestos survey before the next renovation.