Category Archives: Types of Mesothelioma
Some people may have worked with asbestos up to 50 years ago and may not have realised what it was at the time or completely forgotten about it. I.e. you may have been a plumber, carpenter, or electrician during the time when asbestos was widely used (up until the mid 1980’s). If you were employed in any of the professions below – Some of the most likely times you would come across it is during:
- Stripping/ working with wiring (used as an insulator)
- Working on pipes/plumbing (used as pipe lagging)
- Woodworking (used as a floor covering, behind fire doors, paneling)
Employees of businesses that have mined asbestos minerals, or employees that have made asbestos products have a far greater risk of asbestos inhalation than the average person.
What is asbestos?
Asbestos is a naturally occurring rock made of six different fibrous minerals: chrysotile, crocidolite, amosite, tremolite, anthophyllite, and actinolite. The asbestos minerals came from numerous mines throughout the world. The fibres were mixed with cement or woven into fabrics, mats, boards etc.
How can asbestos fibres cause cancer?
The long thin shape of an asbestos fibre may enhance its entry deep into the lung. Following inhalation, fibres of several micrometres in length can enter the respiratory airways, whereas other particles larger than 5 micrometres could not penetrate. Once in the lung – the long fibres may not be cleared by the bodies natural defence mechanism such as ‘macrophage clearance’ macrophages generally mop up foreign bodies, but scientists have discovered that certain stubborn asbestos fibres (such as needle-like shapes of blue asbestos) cannot be cleared by macrophages. These fibres may more easily migrate along tissue planes, lymphatic channels and make their way into the pleural space.
Uncleared fibres can have an inflammatory effect and disrupt normal cell growth –hence leading to cancer, such as ‘mesothelioma’ Mesothelioma is predominantly associated with asbestos exposure. Malignant cells develop within the ‘mesothelium’, a protective lining that covers most of the human body’s internal organs. Mesothelioma can be detected more commonly in the ‘pleura’, the outer lining of the lungs and internal chest wall. Mesothelioma has a long latency period – which means that development of the disease may not manifest itself until 20-50 years later.
When is asbestos harmful?
Asbestos is generally more harmful when it is damaged or deteriorating with age. This is when it is referred to as being ‘friable’ – friable means that it has become brittle and starts flaking. In this deteriorating condition – the asbestos material can release more fibres into the air, increasing the risk of fibre inhalation. Asbestos that is hidden away, i.e. behind a wall cavity and it is 100% intact and not friable will not pose any threat to health. To be completely safe though – any asbestos should be assessed and monitored by an asbestos abatement professional.
What is the likelihood of what will happen if I have been exposed to asbestos?
Being exposed to asbestos does not necessarily mean that you will definitely develop an asbestos-related disease such as mesothelioma or asbestosis. As this depends on how long you have been exposed to asbestos, how many fibres you have inhaled, and what type of asbestos fibres they were.
What are the symptoms of an asbestos related disease?
The symptoms of mesothelioma can be vague and mistaken for other illnesses such as asthma and COPD. Symptoms that have been reported include shortness of breath, due to ‘pleural effusion’ (fluid between the lung and the chest wall), chest pain or discomfort, fatigue, and weight loss.
Mesothelioma is divided into three main types. These types are based on how the cancer cells look under the microscope.
Epitheloid – is the most frequent type accounting for approximately 50 -70 percent of malignant mesotheliomas. Adenocarcinoma (a type of cells that account for most breast cancers) and mesothelioma cancer cells are of similar shape under the microscope, thus the initial diagnosis can be mistaken unless a biopsy is performed (removal of a section of the suspect tissue) and it is only under closer examination of an ultra powerful microscope that the cells can be uniquely identified.
Sarcomatoid – is the least common of the three cellular types and accounts for approximately 7-20 percent of mesotheliomas. Sarcomatoid mesothelioma is very aggressive and cells tend to be more active producing other malignant cells at a greater rate thus spreading to secondary tissues such as, muscles, bone, cartilage, and fat.
Biphasic – is a combination of the above two types and accounts for approximately 20-35 percent of mesotheliomas. Unlike epitheloid and sarcomatoid cells, biphasic cells do not possess a unique cell structure and are typically arranged in groups within a tumour. Multiple biopsies are generally carried out by a Histopathologist to ensure that both epitheloid and sarcomatoid cancer cells are not overlooked.
You can find a description of the ‘symptoms‘ of mesothelioma here