What is Mesothelioma?
Mesothelioma is a form of cancer that develops in the thin layers of tissue that surround the internal organs, called the mesothelium. The types of mesothelioma are named for the area impacted:
- Pleural mesothelioma attacks the pleura (the thin layer of tissue around the lungs).
- Pericardial mesothelioma attacks the pericardium (the tissue around the heart).
- Peritoneal mesothelioma attacks the peritoneum (the tissue surrounding the abdomen).
Mesothelioma cancer is aggressive. Treatments can be productive if the disease is caught in the early stages. However, most people are not diagnosed until the late disease stages due to a long latency period.
Mesothelioma cancer develops decades after asbestos fibers are inhaled or ingested. The fibers cause inflammation and abnormal cell growth. The abnormal cells grow uncontrollably and form tumors, blocking normal cell growth and impeding normal bodily functions. Over time, cancerous cells spread throughout the body, called metastasis.
What is mesothelioma?
Mesothelioma is a rare cancer that grows over 20 to 40 years. About 3,000 people a year receive a mesothelioma diagnosis. By the time most people realize they have mesothelioma, the disease has usually progressed to a point where treatment options are limited. While there is no cure for mesothelioma, researchers are continuing studies to develop advanced treatments.
What is malignant mesothelioma?
Malignant mesothelioma (and mesothelioma) is a cancer that forms in the mesothelium, or the membrane of epithelial cells that surround the thoracic cavity, abdominal cavity, heart and testes.
How are the stages of mesothelioma determined?
Doctors stage mesothelioma, like other types of cancer so they can provide the best treatment options. The stage is determined following extensive testing, including blood work, X-rays, CT scans, biopsies and MRIs. Doctors must determine the point of origin of the disease and if it has traveled throughout the body (metastasized). A precise determination of the disease stage is vital to successful treatment.
What do the mesothelioma stages mean?
The universally accepted staging method for mesothelioma is the TNM system. TNM looks at the tumor growth (T), lymph node involvement (N) and disease metastasis (M). To further clarify the severity of the disease, numbers (ranging from 0 to 4 in some cases) may accompany each letter.
Using information from TNM, doctors identify the stage of the disease. Patients diagnosed with mesothelioma in Stage I, Stage II or early Stage III have treatment options that can include surgery, radiation and chemotherapy. Patients in late Stage III or Stage IV mesothelioma have fewer treatment options, but may be eligible for clinical trials.
What are the different types of mesothelioma?
Mesothelioma is classified based its the location in the body, as follows:
- Pleural mesothelioma (most common) — lungs
- Peritoneal mesothelioma — abdominal area
- Pericardial mesothelioma — heart
- Testicular mesothelioma — testes
Mesothelioma is also classified based on the cell types involved in the tumors. The cell types help doctors determine how the cancer will react to treatment:
- Epithelioid cells — most common and easiest to treat
- Sarcomatoid — aggressive with limited treatment options
- Biphasic — treatment options depend on dominate cell type (either epithelioid or sarcomatoid)
Asbestos has been used for centuries because it was easy to find (it is a naturally occurring mineral), inexpensive (easily dug from asbestos mines) and effective (superior insulating properties).
During World War II, military leaders used the fiber extensively on all vehicles and vessels. After the war and through the early 1980s, asbestos was used in scores of applications, from flooring to faux Christmas tree snow.
During the widespread use, companies that used or mined asbestos knew about the dangers and to great lengths to hide the information.
What causes mesothelioma?
Asbestos is the primary cause of mesothelioma. When microscopic asbestos fibers (either long and needle-like or long and curly) are inhaled, they can become trapped in the lungs, lymph nodes and pleural cavity. Asbestos fibers that are swallowed can also penetrate the lining of the intestines and stomach. Inside the body, trapped asbestos stimulates an immune response. The response causes cells to alter their cellular and molecular features and allows for accelerated abnormal cell growth.
Most of the people diagnosed with mesothelioma are exposed to asbestos in the workplace or during military service. Over 3,000 U.S. workers, military veterans and their families are diagnosed with mesothelioma each year.
For mesothelioma victims and their families, getting complete and accurate information about the disease is vital to treatment. Mesothelioma prognosis and survival rates depend on several factors, including the patient’s age, stage of the disease, cell type involved and location of the cancer.
What is the life expectancy of a mesothelioma patient?
In most cases, patients are diagnosed with mesothelioma when the disease is in the advanced stages and few treatment options are available. Most individuals with mesothelioma survive 12 to 21 months following diagnosis.
There are exceptional cases of patients who have lived longer than five years following diagnosis. Often, those patients are younger, so they can withstand rigorous treatment protocols.
What is the survival rate for mesothelioma?
About 55% of patients diagnosed with mesothelioma in the mid- to late-disease stages typically survive about six months following an initial diagnosis. About 40% survive one year following diagnosis and about 9% live for five years or longer.
A 2019 study that followed Italian shipyard workers for 55 years found asbestos exposure caused a 475% increased mortality from pleural cancer. The researchers said the study conclusion underscored a “urgent need for the prevention of asbestos related diseases through the implementation of an asbestos ban worldwide, including those countries where asbestos is still mined, manufactured and used.”
In general, survival rates are highly individualized due to disparities in the patient’s ages, health and disease metastasis. Recent studies show that advances in treatments, such as cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC), can increase survival rates.
What factors affect a prognosis?
Scientists have determined that several factors play a role in a general mesothelioma prognosis, including:
- Gender: Between women and men with similar disease patterns, women generally have better outcomes.
- Disease stage: Patients with early stage mesothelioma (Stage I and Stage II) respond better to treatment when compared to patients with late Stage III and Stage IV disease.
- Age: Younger and healthier patients respond better to treatment than older patients.
- Cell type: Of the three cell types (epithelioid, sarcomatoid and biphasic), epithelioid cells are generally easier to treat
- Mesothelioma location: Pleural mesothelioma (lungs) is the most common type of asbestos cancer.
- General health: Patients who are physically and mentally sound can better withstand treatment.
A 2019 study by the University of Pittsburgh found six factors associated with an improved mesothelioma prognosis:
- Under age 45
- Epithelioid cell type
- Peritoneal mesothelioma
- Stage I
- Treatment with surgery and chemotherapy
Mesothelioma victims also improve their prognosis when they consult with an asbestos-cancer expert. The leading mesothelioma specialists in the nation have the training, skills, education and experience to provide the best treatments available.
Together, patients and doctors are able to make treatment plans that best suit the patient’s needs. In some cases, the treatments are aggressive to include surgery, chemotherapy and possibly immunotherapy. In other cases, treatment plans include palliative care that reduces or eliminates pain. No matter the path, treatment plans should be customized to the patient’s needs.
When the American Society of Clinical Oncology (ASCO) recently updated its recommendations for mesothelioma treatments, the organization took into consideration all factors that are pertinent to treatment success. In many cases, multimodal treatment (surgery, chemotherapy and radiation or a combination of the three choices) is a good option.
What are the treatment options for a mesothelioma patient?
Multimodal treatment is considered the gold standard for reducing or eliminating asbestos cancer. The combination of chemotherapy, surgery and radiation has proven to have the highest overall success rates. However, many patients are not candidates for all three treatments. Some may instead be candidates for immunotherapy or palliative care.
Some of the leading aggressive treatments include:
- Extrapleural Pneumonectomy (EPP)
In the EPP, physicians strip away the tumor-fill mesothelium (the tissue layer around the organs) or remove an entire diseased lung. While the EPP is considered a potentially curative treatment, it is extreme and reserved for eligible candidates.
- Heated Chemotherapy/ Hyperthermic intraperitoneal chemotherapy (HIPEC)
HIPEC has proven to be highly successful in treating pleural and peritoneal mesothelioma. When coupled with radiation treatment, the multimodal therapy shrinks and removes tumors and kills extraneous cancer cells.
- Pleurectomy/Decortication (P/D)
As the less invasive alternative to the EPP, the P/D treatment removes the diseased tissue and tumor growth surrounding the lung and other areas of the chest cavity. The procedure is followed up with adjuvant therapy (either chemotherapy or radiation treatments). P/D is also called lung-sparing surgery.
Since mesothelioma is difficult to diagnose, specialists use a variety of procedures. However, the most accurate diagnostic tool is a biopsy. For the procedure, physicians remove a small tissue sample and examine it under a microscope. Common types of mesothelioma biopsies include:
- Needle biopsy
Using a fine needle inserted in the lungs or abdominal area, doctors remove tissue or fluid samples
- Surgical biopsy
Doctors surgically remove a larger tissue sample (such as a tumor) through traditional surgery.
- Camera-assisted biopsy
Using a thin, flexible tube with a camera attached, doctors take samples from precise locations.
With biopsy information, specialists determine if the disease is mesothelioma and which kind of cells are involved. Specialists then use other tests, including the following:
- Physical exams and medical history
Mesothelioma specialists typically perform a full physical on patients to understand more about the patient’s general health. They also inquire about the patient’s medical and occupational history to learn more about asbestos exposure.
- Blood tests
Doctors look for biomarkers, or indicators, in the blood to detect cancer cells. Blood tests like MESOMARK, Fibulin-3 and SOMAmer are used to identify specific biomarkers.
- Imaging tests
Imaging tests — X-rays, Echocardiograms, MRIs, CT scans and PET scans — are used to visualize mesothelioma tumors and pinpoint metastasis.
Don’t Be A Misdiagnosis Statistic
Asbestos cancer is often misdiagnosed, which wastes time that could be used for treatment. Patients who suspect they have been exposed to asbestos, even if it was decades ago, should insist on having full diagnostic testing. Mesothelioma is often wrongly identified as lung cancer or general abdominal cancer because the average oncologist does not know the signs and symptoms of mesothelioma. Always seek a second opinion from a mesothelioma specialist.
First Step To Treatment
After a confirmed diagnosis, asbestos-cancer patients who are under the care of mesothelioma specialists are quickly moved into treatment. With the information from the diagnostic testing, specialists tailor a plan to the patient’s unique needs. Multimodal therapy, which can include surgery, chemotherapy and radiation treatment, has shown promising results in eligible patients. Under the care of an asbestos-cancer specialist, patients who were initially misdiagnosed are given encouraging information with more significant treatment options.