Mesothelioma Latency Period

Mesothelioma Latency Period

Malignant mesothelioma often has a long period of latency, in fact the longest of the asbestos-related diseases, before a mesothelioma diagnosis occurs in people. Diagnosis happens by mesothelioma doctors when the disease becomes apparent, but latency refers to the length of time it takes from being exposed to asbestos until the time when the disease becomes apparent in a clinical examination. Latency can be as short as 10 years or as long as 50, but the average length of latency for malignant mesothelioma is 35 to 40 years between exposure and diagnosis.

Because the latency period for mesothelioma can vary from patient to patient, so too does the age of onset of the disease vary. However, most adult mesothelioma cases are diagnosed in patients between the ages of 40 and into their 60s. Child mesothelioma, while rare, does occur in 2 to 5 percent of malignant mesothelioma diagnoses.

A shorter latency period may occur if a patient has had a higher exposure to asbestos. Many of the people who have a short latency period were exposed to asbestos on the job; this is especially true of people with occupations in shipyards as well as the asbestos and insulation industries.

The typical long latency period of this disease is a contributing factor to a poor mesothelioma prognosis. Most cancers respond much better if they are caught early in their development. Because mesothelioma remains under the surface for typically many years, it is often quite advanced once a diagnosis is made.
Forms of Mesothelioma

The different types of mesothelioma cancer are named based on the parts of the body in which the disease occurs. The three primary mesotheliomas are:
Peritoneal mesothelioma
Pleural mesothelioma
Pericardial mesothelioma

Peritoneal mesothelioma is found in the abdomen, while Pleural mesothelioma occurs in the lungs. Pericardial mesothelioma happens in the area of the heart. Where the cancer occurs may also play a part in the latency period; a study showed that 28 years was the average latency period for peritoneal mesothelioma with an average asbestos exposure duration of 5 years, and 35 years latency period with 11 years exposure duration for pleural mesothelioma, but exposure duration could vary widely.
Asbestos Exposure

Exposure to asbestos while on the job appears to be the major cause of mesothelioma. Asbestos was widely used in the United States in the 1960s, and thus the disease tends to become most apparent 30 to 40 years after this, so perhaps the peak of diagnoses in the U.S. will have been between 2000 and 2004. Because laws on exposure to harmful elements while on the job were put into place, it is expected that these statistics will not be on the rise. Australia and Europe may see a peak in 2010 to 2019, and it remains to be seen what will occur in third world countries without the benefit of strong occupational hazard laws in place.
The Future

These statistics may be in flux, however, for several reasons. They include:
better health care and better food, people are living longer after retirement
better occupational exposure regulations, workers are no longer exposed to high levels of asbestos
better occupational exposure regulations, workers are no longer exposed to high levels of asbestos
Fewer cases of bronchogenic cancer, which may be fatal in workers exposed to asbestos, before the mesothelioma has made a physical impact

Due to these factors, we may see more cases of new-onset mesothelioma.

Secondary or limited exposure to asbestos is a contributing factor to the difficulty encountered when trying to figure out exactly when asbestos exposure occurred. However, one of the consequences of the World Trade Center disaster may help researchers to better understand this disease. Because rescue, cleanup, recovery and volunteer personnel were exposed to asbestos along with other airborne contaminants, long-term studies of these people are under way, which may assist researchers in gaining more knowledge about this serious disease.

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Mesothelioma Information

Mesothelioma Information

As with any disease or health condition, mesothelioma researchers have, over time, collected statistical information about mesothelioma. These statistics can help us learn about the proclivities of the disease and its incidence and potentially help future patients as we learn more about mesothelioma.
Incidence of Diagnosis

New cases of mesothelioma are diagnosed in between 2,500 and 3,000 Americans each year. These numbers, while significant, would indicate that mesothelioma is still a relatively rare disease, though incidence is expected to rise in the next decade according to projections.
Age at Diagnosis

The first diagnosis of mesothelioma typically occurs in men and women between the ages of 50 and 70 years. Mesothelioma patients, certainly, have been diagnosed at ages younger than 50 and older than 70, but diagnoses for those age groups are considered statistical anomalies.
Does Mesothelioma Occur in a Particular Sex or Racial Demographic More than Another?

Mesothelioma is much more common in men than women, due mostly to occupational asbestos exposure being more common among men of industrial labor sites. That is not to say, however, that women cannot be diagnosed with mesothelioma. In fact, recent evidence suggests that mesothelioma incidence in women may rise in the coming years as secondary exposures to asbestos can manifest in the form of a positive mesothelioma diagnosis. Also of note is that mesothelioma is much less common among African Americans than in Caucasians, the reasons for which researchers are still investigating.
What are Typical Patient Survival Rates Following a Mesothelioma Diagnosis?

As mesothelioma is often diagnosed in its advanced stages, the mesothelioma prognosis is sometimes poor with life expectancy being little more than a year following diagnosis. If diagnosed early enough however, patient prognoses increase dramatically. Patient survival rates are often contingent on the treatments available to the particular patient. In early mesothelioma stages, tumors eligible for mesothelioma surgery and will result in improved prognoses over those who are diagnosed with stage 3 mesothelioma or stage 4 mesothelioma. As new and alternative mesothelioma treatments are researched and employed in the future, it is realistic to anticipate an improvement in patient survival rates.
Other Mesothelioma Information
Mesothelioma Latency Period

Typically, there is a great deal of time between an individual's exposure to asbestos and the development of asbestos-related health complications. Mesothelioma is associated with a long-latency period (often 20-50 years) after exposure. Over a long period of time, lodged asbestos fibers slowly inflame the lung's external tissue, often serving as a pre-cursor to the development of malignant mesothelioma.
Adult Mesothelioma

Mesothelioma is most common in adults. Adults who have asbestos exposure history are typically those most at risk for the development of malignant mesothelioma. It can take many years for those exposed to asbestos exposure to exhibit the effects of exposure and, as such, mesothelioma is most often diagnosed in older individuals, often up to 40 years following exposure.
Child Mesothelioma

Childhood diagnosis of malignant mesothelioma is extremely rare, although it has been documented. Mesothelioma is known only to be caused by exposure to asbestos and takes many years following exposure to asbestos to manifest in adults. Generally speaking, childhood mesothelioma is considered to be unrelated to asbestos exposure.
Mesothelioma and Women

Many women that have been diagnosed with mesothelioma had no direct exposure to asbestos from working in industrial job settings. Instead they discover that they are victims of second-hand asbestos exposure that occurred while washing their husband's clothes that came home from work with asbestos fibers on them.
Mesothelioma Prevention

Mesothelioma is known only to be caused by exposure to asbestos, a naturally occurring fibrous mineral that was used for many years as an industrial insulation component. As such, the best mesothelioma prevention is the avoidance of exposure to asbestos. However, in recent years, physicians and cancer specialists have been developing a mesothelioma vaccine that will arm the body's immune system with cancer fighting anti-bodies and antigens in those who are at risk for the development of mesothelioma.
Mesothelioma Vaccine

Recent studies by researchers in the Netherlands have found promising results in preventative therapies for mesothelioma. Using cancer-fighting antigens within the body's immune system, mesothelioma patients have responded positively in most cases when treated with the mesothelioma vaccine. The hope is now that this therapy can be applied to those who may be at risk of developing mesothelioma in the future, particularly those who have been exposed to asbestos but have yet to develop asbestos disease.
Medical Timeline

Historical timeline containing important facts and developments related to the manufacture and use of asbestos and documented cases of mesothelioma cancer and other asbestos related diseases.
Mesothelioma Misspellings

The word “mesothelioma” is often misspelled by people searching on the internet for information about this asbestos cancer. In this section we list some of the most common misspellings that we have seen individuals use in their internet searches for mesothelioma.
Mesothelioma Misconceptions

There are several common myths and misconceptions about mesothelioma. Learn more about what the true facts are about this asbestos-related disease.
Mesothelioma Disease

Mesothelioma cancer is a rare disease that attacks the cells of the tissue that lines the body cavity called the mesothelium. It’s only known cause is exposure to asbestos fibers.

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Mesothelioma Prognosis

Mesothelioma Prognosisv

When an individual is diagnosed with mesothelioma or any other kind of cancer, one of the first questions they will have is “How long do I have to live?” This is a scary question - and a hard one to ask - but one for which most cancer patients will eventually seek an answer.

It is often very difficult for oncologists and members of a patient’s medical team to give a definitive answer to this query. Indeed, every case is different and cancer can be an unpredictable disease. Sometimes, cases that look hopeless turn out to be not so bleak. In other cases, cancers that don’t look so bad progress quickly and result in an untimely death.

Overall, the prognosis has been rather grim for mesothelioma patients during these past few decades. Malignant mesothelioma is extremely aggressive and has a long latency period. Hence, cases are usually not detected until the disease has reached the advanced stages of cancer. As a result the prognosis for such patients is often not favorable; the mesothelioma survival rate following diagnosis is usually just a year or two. That doesn’t mean, however, that there won’t be exceptions and that this dour outlook will not change in years to come, especially as more and better treatments are developed.
Determining Prognosis

Currently, a number of different issues determine the mesothelioma patient’s prognosis. These include:

Type - Mesothelioma is classified as one of three types, depending on the tissues involved. The epithelial type accounts for about 50 percent of all cases, sarcomatoid mesothelioma is seen in 15 percent of diagnosed patients, and 35% have the mixed type of the disease. Those with epithelial mesothelioma have a better survival rate than the other types.

Location - Mesothelioma is also classified on the basis of location. For example, pleural mesothelioma, which attacks the lining of the lung, is the most common, accounting for approximately 8o percent of all cases. Those with this type of cancer have the best rate of survival. Peritoneal mesothelioma, found in the lining of the abdomen, is the next most common and is diagnosed in about 10 -15 percent of mesothelioma victims. It is generally harder to treat. Less common types are very difficult to treat, including pericardial and testicular mesothelioma.

Stage of the disease - The prognosis for mesothelioma cancer depends on how early the disease is diagnosed and how soon treatment can begin. Because of the disease’s extended latency period, it is often not diagnosed until it has reached Stage 3 or 4, when mesothelioma symptoms finally appear. Sadly, many of these symptoms are common to a wide range of respiratory diseases including many that are less serious, like the flu or pneumonia. This often results in misdiagnosis.

Metastasis - When a mesothelioma diagnosis is finally made, oncologists will often find that the cancer has spread - or “metastasized” - from the location of the primary tumor - usually the pleura - to other parts of the body, often to the nearby organs as well as the lymph nodes. The extent of the metastases will determine what type of treatment is recommended as well as the prognosis.

General health of the patient - Simply put, younger and stronger patients with mesothelioma live longer than those of advanced age who have extant health problems. Seniors are often dealing with issues like heart disease, diabetes, and high blood pressure, making mesothelioma surgery as well as traditional cancer treatments much more risky and severely limiting treatment options.
Additional Mesothelioma Prognosis Factors
Mesothelioma Life Exptectancy

Life expectancy for those diagnosed with malignant mesothelioma depends on a number of factors including, general patient health, cancer stage at diagnosis, and the eligibility of the patient for certain treatment options. Those diagnosed with early stage cancer and in generally good health will have a more favorable prognosis than those diagnosed with later-stage disease.
Mesothelioma Survival Rate

Most survival rates for cancer are quoted in regards to what is commonly known as the relative five-year survival rate. This indicates the number of patients who are still alive five years after they are diagnosed with the disease. Currently, the five-year survival rate for mesothelioma victims is just 10 percent. Though this seems like a grim number, it is indeed higher than it was about 10 years ago and much higher than it was 20-30 years ago.

The current one-year survival rate for mesothelioma patients is about 40 percent. This has also increased significantly in the last 10 years. Unfortunately, however, the prognosis for most mesothelioma patients remains poor overall. Many still die less than a year after diagnosis, with the average survival rate being 10-11 months, according to the American Cancer Association.
Mesothelioma Remission

Mesothelioma is one of the most aggressive types of cancer and can quickly metastasize from its origin into the lungs, abdominal cavity, and lymph nodes. As a result, very few mesothelioma patients go into remission. However, if treated properly and early enough, many patients have been able to extend survival rates long beyond previous expectations. Treatment options include surgical resection, chemotherapy, and mesothelioma radiation.
Mesothelioma Cure

While there is still no cure for mesothelioma, significant strides have been made over the past ten years in the area of mesothelioma research. As a result there are new tests that have been developed to help medical professionals detect the cancer sooner and there is a wide range of new treatment options available that can lead to improved life expectancy for mesothelioma victims. Patients who are diagnosed with early-stage disease may survive many years if the cancer is treated early with surgery, chemotherapy, and managed radiation therapy. Many patients have also had success through the utilization of alternative therapies in conjunction with conventional cancer treatments.
Mesothelioma Survivors

While there is currently no cure for mesothelioma, many patients have had success in managing their cancer with not only traditional treatments like chemotherapy and surgical methods, but also through the use of nutritional supplements, palliative therapies, and body-stress reduction techniques. Some patients diagnosed with mesothelioma have survived many years after what was an initially unfavorable prognosis.
Improving the Mesothelioma Prognosis

During the last decade, the plight of mesothelioma sufferers has gained more attention and more research dollars have been funneled towards the study of this disease and the discovery of new and novel drugs and treatments to provide more hope of a better prognosis for the mesothelioma sufferer.

Scientists have been working on new tests that strive to diagnose the disease at an earlier stage. For example, the Mesomark® assay is a simple blood test that measures the rate of Soluble Mesothelin-Related Peptides (SMRP) in the blood. This biomarker is released by mesothelioma cells into the bloodstream and SMRP can be elevated for many years before symptoms appear and an actual diagnosis of the disease is made. This tool for early diagnosis could potentially save hundreds of lives.

Treatments with new chemotherapy drugs like Alimta® and procedures that deliver more targeted radiation to the tumor have also helped to add to a mesothelioma patient’s life expectancy. In addition, experimental treatments such as immunotherapy, gene therapy, and photodynamic therapy have shown some success in treating this difficult disease.

Each new step in the field of mesothelioma research improves the mesothelioma prognosis little by little and provides additional hope for mesothelioma-affected individuals and their loved ones.
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Mesothelioma Stages

Mesothelioma Stages

How is mesothelioma staged?

Staging is the process of finding out how far the cancer has spread. Staging of mesothelioma is based on imaging studies such as x-rays, CT scans, and MRI scans. The mesothelioma treatment and life expectancy for patients with the disease largely depends on the stage (extent of spread) of their cancer. Since pleural mesothelioma occurs most frequently and has been studied the most, it is the only mesothelioma for which a staging classification exists.
Mesothelioma Staging Systems

Today, there are three primary staging systems used to assess how far mesothelioma cancer has spread and each system uses four stages to describe the progression of the disease. It is the definition of each stage within the various systems that can vary slightly.
Butchart Staging System

The staging system most often used for mesothelioma cancer is the Butchart system and is focused on defining the location of the primary tumor mass in body for each stage. The system doesn’t address how many cancer cells are present, how big the tumor is or the level of cancer present in the body overall.
TNM Staging System

The TNM Staging System, developed by the American Joint Committee on Cancer (AJCC), is similar to staging systems used for other types of cancer. It considers the characteristics of the tumor (T), whether or not lymph nodes are involved (N) and if the cancer has metastasized to other locations in the body (M).
Brigham Staging System

The Brigham Staging System also has four stages of progression and is very similar to the TNM Staging System. The primary difference between the two is that in addition to defining the location of the tumor, and assessing lymph node involvement and the presence of metastatic disease, the Brigham System also helps assess the possibility for and effectiveness of surgical intervention at each stage.
The Stages of Mesothelioma

The four stages of mesothelioma, as noted above, vary slightly within each system but can be generally characterized as indicated below. Please click into the individual pages to get more information about each stage in general and as is it defined within each staging system:
Stage 1 Mesothelioma

In Stage 1 the tumor is localized, there is no lymph node involvement and the cancer has not spread to other organs or tissues.
Stage 2 Mesothelioma

In Stage 2, the tumor is larger and has invaded the lung or diaphragm. Lymph nodes may also be involved.
Stage 3 Mesothelioma

In Stage 3, mesothelioma has invaded a single region or area such as the chest wall.
Stage 4 Mesothelioma

In Stage 4, mesothelioma has invaded multiple regions such as different areas of the chest wall, the diaphragm and/or the pericaridium. Lymph glands are also involved and the cancer has spread to other organs.
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Mesothelioma Types

Mesothelioma Types

Types of Mesothelioma by Site
Pleural Mesothelioma

Malignant pleural mesothelioma often originates within the chest cavity and can, at times, involve the lung. This particular form of mesothelioma can metastasize to numerous organs in the body - even the brain - and tends to do so more frequently than not.

Pleural mesothelioma is not always easily detectable. Frequently, in the early stages of the disease, such as stage 1 mesothelioma, symptoms may be mild. Patients usually report pain in one area of the chest that never seems to go away, weight loss and fever. Occasionally, other symptoms are more severe and include problems with breathing due to fluid build up in the chest. A CT Scan of the chest area has proven to be the best test for identifying how far along the disease has progressed.

Frequently serum markers are used to diagnose of various forms of cancer. Mesothelioma cannot be diagnosed using this method as no serum markers currently exist. If high levels of hyaluronic acid are present it may be possible to distinguish mesothelioma types from other types of cancer or to determine the effectiveness of a treatment protocol.

The mesothelioma survival rate for patients diagnosed with pleural mesothelioma typically is not high as patients often do not live beyond seventeen months from the onset of symptoms. Only 8% of those with a mesothelioma diagnosis will live three to five years from the onset of mesothelioma symptoms.
Pericardial Mesothelioma

Pericardial mesothelioma is the least common form of mesothelioma. Pericardial mesothelioma, as the name suggests, involves the heart. This rare type of mesothelioma cancer invades the pericardium, the sac that surrounds the heart. As the cancer progresses, the heart is not able to deliver oxygen as efficiently to the body causing further decline in health at an increasingly rapid rate. The symptoms most commonly associated with pericardial mesothelioma mimic those of a heart attack: nausea, pain in the chest and shortness of breath.
Peritoneal Mesothelioma

Peritoneal mesothelioma originates in the abdomen and will frequently spread to other organs in area including the liver, spleen or bowel. Severe abdominal pain is the most common complaint that patients present to mesothelioma doctors. There may also be a discomfort level with fluid buildup in the abdomen as well. Other symptoms of peritoneal mesothelioma may include difficult bowel movements, nausea and vomiting, fever and swollen feet.

The survival rate is even worse for those diagnosed with peritoneal mesothelioma with patients typically surviving only ten months from the time that they first started experiencing the symptoms noted above.
Types of Mesothelioma Tumors
Malignant Mesothelioma

Malignant mesothelioma is an uncommon form of cancer and of all asbestos related diseases, the most serious. The symptoms associated with the disease make it difficult for doctors to diagnose. Often, by the time that a proper diagnosis is made, the disease has progressed to a point where patients do not respond well to treatment therapy. Malignant mesothelioma is caused almost exclusively by the inhalation of airborne asbestos particles. Another unique factor associated with the disease is that there can be a long latency period between the time of asbestos exposure and the actual manifestation of the disease in the form of malignant mesothelioma.
Benign Mesothelioma

Benign mesothelioma, or non-malignant mesothelioma, is much easier to treat than the malignant form of the cancer and can be treated successfully in many cases.
Mesothelioma Cell Types
Epithelial Mesothelioma

Epithelial Mesothelioma is the most common cell type and accounts for approximately 50-75% percent of all diagnosed cases each year. These cells are uniform in shape, with an elongated pattern that makes them easily distinguishable when viewed under high magnification. These types ofcancercells are adenocarcinomas, malignancies which are more commonly associated with pure lung cancers as opposed to cancers of the mesothelium.
Sarcomatoid Mesothelioma

Sarcomatoid mesothelioma is a less common cell type, accounting for between 7 and 20% of mesothelioma cases each year. These cells grow forth out of supportive structures, such as muscles and bones.
Biphasic Mesothelioma

Biphasic mesotheliomas are those with a mix of epithelial and sarcomatoid cell types. Mesothelioma treatment options do not vary greatly for different cell types, but often sarcomatoid mesotheliomas are more difficult to treat as a result of the surrounding affected tissues that they spread from.
Papillary Mesothelioma

Papillary mesothelioma, also known as well-differentiated mesothelioma, is a form of the asbestos cancer that typically affects women. In many cases this cell type is benign and not likely to spread to other organs in the body.
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