It is not uncommon for people to ask the question, “What is mesothelioma?” The disease is rare, often making it difficult to understand or prepare for. If you or a loved one has been diagnosed with mesothelioma, it’s possible that, even now, you don’t fully understand the disease. In order to comprehend the condition more completely, it’s important to look at some mesothelioma statistics.
First, let’s take a look at some of the basics of the disease. Mesothelioma is an aggressive type of cancer that is usually found in the lining (or mesothelium) of various organs. It most often occurs in the lung lining (or pleura).
The only known cause of the disease is exposure to asbestos, a silicate substance that was frequently used in building materials like insulation in the 20th century. Most people develop mesothelioma after exposure to asbestos on the job.
Mesothelioma has quite a long latency period, which is the time it takes from the initial exposure to asbestos to the moment symptoms begin to appear. It can take between 10 and 50 years (usually between 30 and 40) for mesothelioma to start showing any signs. So, let’s say an individual was exposed to asbestos in the 1980s. If mesothelioma took hold, symptoms of the disease may just now be cropping up.
Keep reading to find out more mesothelioma stats.
How Often is Mesothelioma Diagnosed?
In the United States, cases of mesothelioma are quite rare. Only 2,000 to 3,000 new cases are diagnosed each year. Between the 1970s and 1990s, cases of mesothelioma ballooned in the U.S. Since then, the number has remained relatively stable with a slight decline seen in recent years.
Worldwide, the number of new annual cases ranges from 30,000 to 60,000. Most people only have a 0.04% chance of developing the disease at some point in their lifetime. While this makes a diagnosis relatively uncommon, anyone who has been exposed to asbestos could be at risk.
Twenty million people could theoretically develop the disease based on how much asbestos they were exposed to.
In the United States, over 50,000 people were diagnosed with mesothelioma from 1999 to 2014. That makes it an average of about 1 diagnosis per 100,000 residents. Not every location throughout the world averages that amount, however. Three countries have a higher rate of 3 diagnoses per 100,000 residents.
- The United Kingdom
In many developed countries, the mesothelioma incidence rate is between 7 and 40 per 1 million residents. This can largely be attributed to the increased usage of asbestos-containing commercial products in those countries. Globally, however, the incidence rate is only about 1 to 6 per 1 million individuals.
These mesothelioma statistics, however, might be skewed because of a lack of proper reporting and recording in less developed countries. Incidence rates might be higher in countries where health care options aren’t as abundant. Incidence rates in the developed world are also expected to grow by 5 to 10% by 2020.
Men are typically 4 times more likely to incur a mesothelioma diagnosis than women. This is due to the fact that men are more often employed in blue collar jobs that involve exposure to asbestos. Over 90% of all cases are diagnosed in people who are 55 years of age or older. It is exceedingly rare to be diagnosed with the disease if you are under 45.
There are three primary types of mesothelioma:
- Pleural mesothelioma (affects the lung lining or pleura and occurs in between 70 to 90% of cases)
- Peritoneal mesothelioma (affects the abdominal cavity lining and occurs in between 10 to 20% of cases)
- Pericardial mesothelioma (affects the heart lining or pericardium and occurs in only around 1% of cases)
A much rarer fourth type of the disease (testicular mesothelioma) has been reported less than 100 times throughout the world and is not well-understood. Pleural mesothelioma is the most common type of the disease and the one that most people recognize. The primary way mesothelioma develops is through the inhalation of asbestos fibers.
It is much easier for those fibers to become lodged in the lining of the lungs rather than the lining of the abdominal cavity or heart, which accounts for the higher incidence rates of pleural mesothelioma.
Mesothelioma and Asbestos Facts
An abundance of scientific evidence has linked exposure to asbestos to the incidence of mesothelioma. But, how and why does asbestos exposure occur in the first place? For starters, asbestos wasn’t originally thought of as a destructive and toxic material.
When it first started being inserted in commercial products in the mid-19th century, it worked as an excellent fireproof and heat-resistant material. That’s why it’s commonly found in insulation or products that can reach high temperatures.
By the 1960s and 1970s, studies had thoroughly proven the link between asbestos and a variety of health issues, including mesothelioma. Despite this, asbestos production peaked at that time in the United States with 803,000 metric tons being produced in 1973 alone. Two years prior, the Occupational Hazards and Safety Administration (OSHA) had enacted the first regulations against the production and use of asbestos in the country.
Over the following decades, OSHA helped curtail the production of asbestos through stricter regulation. In 2002, the last asbestos mining operation in the United States shut down. Despite this, it remains legal to import products that contain asbestos into the U.S. Over 61 countries globally have enacted full or partial bans of asbestos and more are following suit. It does not appear as if the United States will be one of those countries, at least in the near future.
In 2015, over 25 million tons of asbestos was disposed of in the U.S. In 2016, 340 tons of the substance was imported into the country. While asbestos poses less of a risk than it did 40 or 50 years ago, it is still clearly an issue. Even products that no longer allow asbestos can still be found in older homes, schools, offices, factories, and a variety of other locations.
Globally, around 125 million people have been exposed to asbestos to some degree. There are six different types of asbestos, but the chrysotile variety is the one most commonly used in commercial products. Crocidolite and amosite varieties are much rarer (and are prohibited from even being imported into the United States), but their length and thinness makes them the most dangerous.
Mesothelioma Facts on Survival Rates
A “survival rate” is a measure of how long a certain cross-section of people survives with mesothelioma after diagnosis. In general, the prognosis for the disease is very poor, with an average 5-year survival rate between 7 and 9%. This means that only 7 to 9% of all those diagnosed with the disease will live for 5 years after diagnosis. Most people diagnosed with mesothelioma live for between 1 and 2 years at the most.
But, there are numerous other factors that can help improve survival rates for many people. Treatment, of course, is one of those options. Doctors will often offer some combination of surgery, chemotherapy, and radiation therapy to their patients. As you might expect survival rates are vastly improved when all three treatment options are applied.
With just surgery, survival rates are:
- 1 year: 52%
- 2 years: 34%
- 3 years: 21%
With surgery and chemotherapy together, survival rates are:
- 1 year: 56%
- 2 years: 29%
- 3 years: 17%
Surgery and radiation therapy provide survival rates of:
- 1 year: 66%
- 2 years: 39%
- 3 years: 22%
Finally, survival rates when all three methods are combined are:
- 1 year: 76%
- 2 years: 51%
- 3 years: 37%
Clearly, all three of the most common methods of treatment together provide much better results than limited or no treatment. Surgery often removes tumors and diseased tissues while chemotherapy and radiation therapy can kill any stray cancer cells.
Some newer treatment options are improving survival rates for peritoneal mesothelioma (occurring in the lining of the abdominal cavity). The procedure involves a combination of cytoreductive surgery (which seeks to remove cancerous cells in the abdomen) and hyperthermic (heated) intraperitoneal chemotherapy (HIPEC). The HIPEC treatment involves injecting heated chemotherapy medications right onto tumor sites during open surgery. With this treatment, the 5-year survival rate is over 50%.
Unfortunately, only around 20% of mesothelioma patients are good candidates for major surgery. In fact, between 20 and 30% of all patients will receive no treatment whatsoever. Most individuals are diagnosed when the disease has already spread to several other parts of the body, making major surgery unviable. This is usually stage 3 or stage 4 mesothelioma. Stages 1 and 2 of mesothelioma have the best prognoses and survival rates.
For pleural mesothelioma, survival rates for all stages are:
- Stage 1, two years: 43%
- Stage 1, five years: 15%
- Stage 2, two years: 38%
- Stage 2, five years: 10%
- Stage 3, two years: 28%
- Stage 3, five years: 7%
- Stage 4, two years: 17%
- Stage 4, five years: 1%
Clearly, the downward trend of survival rates means that life expectancies are often very low for stage 3 and stage 4 mesothelioma.
Overall survival rates for pleural mesothelioma follow that same trend:
- 1 year: 73%
- 3 years: 23%
- 5 years: 12%
- 10 years: less than 5%
Peritoneal mesothelioma has a slightly better prognosis, largely due to the advent and increased usage of HIPEC treatments.
Survival rates are:
- 1 year: 92%
- 3 years: 74%
- 5 years: 52%
- 10 years: 39%
As research progresses, survival rates are bound to improve across the board.
One of the grimmer mesothelioma facts is that most people diagnosed with the disease will pass away within a year or two of diagnosis. Between 1999 and 2015, the United States experienced over 45,000 mesothelioma-related deaths, an average of 2,500 per year. Around 8 people per million lose their lives to mesothelioma each year.
Throughout the world, the annual mesothelioma death toll is over 30,000.
Chances of long-term survival are slim, but cases have happened. The best predictor of long-term survival is age, with those diagnosed before age 45 having a much better outlook. Unfortunately, most mesothelioma diagnoses occur after age 55, and many occur when the patient is 65 or older. Early detection is also important for long-term survival. As noted above, survival rates for stage 1 or 2 of mesothelioma are generally much better.
Clinical Trials and Emerging Treatments
In addition to the progress of traditional treatment methods, there are also many different emerging methods that can prove to be helpful for a wide variety of mesothelioma patients. Emerging treatments are most often tested and researched during clinical trials. Anyone who is diagnosed with mesothelioma can join a clinical trial to receive the newest treatments.
Traditionally, three treatment options are provided to patients, but, with four treatments, patients survive a median length of over 2 years. There have been over 300 mesothelioma clinical trials completed throughout the world. The leader in clinical trials for the disease is the United States.
Some emerging treatments that you may find during clinical trials include:
- Gene therapy
- Epigenetic therapy
- Photodynamic therapy
Not every clinical trial offers emerging treatments, however. Some are performed to identify the efficacy of often existing chemotherapy drugs. Some of these drugs have already been approved for use for other cancers. It can take between 12 and 15 years for new chemotherapy drugs to reach approval for use in treating mesothelioma.
Clinical trials are often performed by a wide range of agencies, organizations, and corporations, and they are often well funded. In some cases, the sponsors of the trial will help offset the cost of treatment for patients. Clinical trials will also often include other, more traditional treatment methods to ensure that patients are getting the best treatment possible.
At the end of the day, mesothelioma is a pernicious disease. No mesothelioma statistics can estimate the toll the disease takes on patients and their families. But, as research progresses, a cure will always be on the horizon. It’s always important to hold out hope that newer treatment options will provide a happy ending for all involved.