Understanding Mesothelioma: Symptoms, Causes, and Diagnosis

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• What is Mesothelioma?
• Mesothelioma Symptoms
• Asbestos Exposure History
• Occupational Asbestos Exposure
• Secondary Asbestos Exposure
• Current Asbestos Use
• Full Transcript

What is Mesothelioma?

Mesothelioma is a rare and aggressive form of cancer. Dr. Dean Fennell, MD, describes it as a cancer that predominantly affects the lining of the chest cavity, known as the pleura. The tumor arises in a layer of cells outside the lung and can spread in a sheet-like manner, constricting the lung. While most common in the chest, Dr. Dean Fennell, MD, notes that mesothelioma can also occur in the abdominal cavity (peritoneal mesothelioma) and, much more rarely, around the heart or in the testes.

Mesothelioma Symptoms

The most common symptom leading to a mesothelioma diagnosis is shortness of breath. Dr. Dean Fennell, MD, explains that this is frequently caused by a buildup of fluid in the chest cavity, a condition known as a pleural effusion. Patients, who are often otherwise fit and may have never smoked, experience a rapid onset of breathlessness upon exertion. This symptom typically prompts a chest X-ray, which reveals the fluid accumulation and triggers further investigation that ultimately leads to the mesothelioma diagnosis.

Asbestos Exposure History

Mesothelioma is uniquely caused by exposure to asbestos, a toxic environmental contaminant. Dr. Dean Fennell, MD, emphasizes this direct causal link during his discussion with Dr. Anton Titov, MD. The time between initial asbestos exposure and the development of mesothelioma symptoms is typically long, often spanning 20 to 30 years. This long latency period is a key reason why mesothelioma is frequently diagnosed at a late stage, making treatment more challenging.

Occupational Asbestos Exposure

Many patients have a clear history of occupational asbestos exposure. Dr. Dean Fennell, MD, states that professions like carpentry, plumbing, and electrical work often involve direct contact with asbestos-containing materials. Patients in these trades can usually provide a detailed account of their exposure history from decades prior. This history is a critical piece of the diagnostic puzzle, helping clinicians determine the probability of mesothelioma alongside other test results.

Secondary Asbestos Exposure

Not all mesothelioma patients have a known occupational exposure history. Dr. Dean Fennell, MD, discusses cases involving individuals like nurses or teachers who did not directly work with the material. These individuals may have been exposed to asbestos fibers in their general work environment. Furthermore, Dr. Dean Fennell, MD, highlights well-documented instances of secondary, or "passive," exposure. This occurs when asbestos fibers are brought into the home on the clothing of a family member who worked with it, potentially exposing spouses and children.

Current Asbestos Use

Despite a worldwide ban, asbestos remains a present-day concern. Dr. Dean Fennell, MD, informs Dr. Anton Titov, MD, that in the UK, asbestos was permitted in building construction until 1999. Many other countries continue to import and use asbestos because it is still actively mined in various parts of the world. Dr. Fennell suggests that the epidemic of asbestos-related cancers seen in the West over the last 50 years could be mirrored in these countries in the future, leading to new waves of mesothelioma diagnoses.

Full Transcript

Dr. Anton Titov, MD: What is mesothelioma?

Dr. Anton Titov, MD: What are the typical symptoms of mesothelioma, and why is mesothelioma usually diagnosed at a late stage?

Dr. Dean Fennell, MD: Mesothelioma is cancer that predominantly affects the lining of the chest cavity. This is outside the lung. Mesothelioma arises in a layer of cells that lie outside the lung. This causes a tumor that can spread like lava to form a sort of a sheet, which constricts the lung to cause symptoms for the patient.

Mesothelioma can also affect other linings in the body, not just within the chest cavity, but also within the abdominal cavity, and possibly even in the testes or around the heart. These are much rarer forms, however, of this cancer.

Mesothelioma is caused by asbestos. This really makes it a quite unique disease that arises due to toxicity from this environmental contaminant. Mesothelioma is a cancer that can cause symptoms that allow the patients sometimes to present with shortness of breath because they have a buildup of fluid in the chest. This is a very common reason for people presenting to their doctors.

Actually, people may have been extremely fit, never smokers, who become breathless on exertion over a relatively short period of time. They have a routine chest X-ray, which shows the accumulation of fluid. This triggers investigations that lead to the diagnosis of mesothelioma.

Dr. Anton Titov, MD: A lot of people are never smokers, but they have been exposed to asbestos or other types of mineral fibers. Can the history usually be determined from some sort of exposure? Are most people just completely unaware that they have been exposed to the mineral fibers and, specifically, to asbestos?

Dr. Dean Fennell, MD: Very good question. There are many professions where exposure to asbestos is something that the patient will know about and be able to recall. For example, suppose a patient is a carpenter, a plumber, or an electrician. In that case, they may well be able to give a very good account of their prior exposure, usually 20, maybe 30 years previously, where we can build this into the history of this patient's condition.

And almost certainly we use this to guide the probability that this patient has mesothelioma, alongside all the test results we would acquire. However, there are patients in whom histories do not reveal a known exposure to asbestos. We see a lot of nurses or teachers who never work with the material in the same way that a plumber might, for example.

But they nevertheless would have been exposed to asbestos in their working environment, in their working lives. There are some instances that are well documented where people may have been exposed in the very early even childhood actually, or a spouse perhaps, who may be exposed simply because another member of the family worked with asbestos, brought their clothes into the house, perhaps on overalls or something like that. And the contamination was through that sort of passive exposure to the asbestos.

Dr. Anton Titov, MD: Is asbestos at this point banned from production and distribution, or is it still widely used in the environment? How does it work? I realize that, for example, in Russia, there is actually a town called Asbestos. And that reflects a lot of history. But how does it look in the present?

Dr. Dean Fennell, MD: Yeah, so there has been a worldwide ban on asbestos. We know that, for example, in the UK, we were able to build properties actually, with the inclusion of asbestos up to 1999. So a building up until 1999, despite the worldwide ban, could have asbestos in it.

Many countries have continued to import asbestos. And this is because, of course, it's still being mined. I believe Trump even talked about the possibility of it being mined at some point during his presidency. So it is still clearly a material that is being traded and one that is being used around the world.

And we expect that, like in the West, where we've seen an epidemic of cancer secondary to the environmental contamination by asbestos over the last 50 years. But this could be mirrored in other countries where asbestos is still being used.