What is Mesothelioma and is it Lung Cancer?

Mesothelioma is a rare and deadly cancer that can form in the tissue lining of the lungs, heart, abdomen, or testicles. Many wonder if mesothelioma is a form of lung cancer, but the two are different. Although these two cancers are associated with the lungs, mesothelioma is not lung cancer. Lung cancer forms inside the lungs, whereas mesothelioma develops in the tissues lining the lungs, diaphragm, and chest cavity.

Mesothelioma Diagnosis

Doctors can locate and diagnose tumors through physical exams and various tests. If concerned about your occupation and medical histories, it is best to inform your doctor. Medical professionals will be able to examine symptoms and determine whether further testing is necessary.

Many people, when diagnosed, are confused by what mesothelioma cancer is.

  • Can you survive this cancer? The survival rate for mesothelioma is typically 4-18 months, but some patients live longer than ten years.
  • What is my life expectancy? The life expectancy after diagnosis is generally poor; about 46% of patients live one year after being diagnosed.

Mesothelioma Types and Symptoms

Mesothelioma is a rare form of cancer that originates from mesothelial cells in various body parts such as the chest, heart, abdominal cavities, and testicles. Malignant mesotheliomas are cancers that primarily start in the mesothelium of the chest cavity, the pleura, the abdominal cavity, the peritoneum, or the heart cavity, the pericardium.

Pleural Mesothelioma

Beginning in the pleura, the membranous tissue surrounds the lungs and chest cavity in pleural mesothelioma. The most common type of mesothelioma accounts for up to 80% of cases each year. Pleural mesothelioma is often treated with chemotherapy, surgery, radiation, and immunotherapy. This type often starts with symptoms such as chest pain and persistent coughing. In later stages, lumps may form beneath the chest skin. Patients are often short of breath, easily fatigued, and lose weight without trying to.

Peritoneal Mesothelioma

This form begins in the peritoneum, the tissue surrounding the organs in the abdominal cavity. The second-most common mesothelioma form as it accounts for around 15 to 20% of diagnoses. Peritoneal mesothelioma is typically treated with surgery, chemotherapy, and immunotherapy. Symptoms begin with belly swelling and stomach pain caused by growing tumors. Nausea, vomiting, and constipation are all symptoms, as well. Advanced cancer will provide unexplained weight loss and lumps in the abdomen.

Pericardial Mesothelioma

Pericardial cancer occurs in the tissue sac covering the heart, known as the pericardium. With fewer than 50 diagnoses in the U.S. each year, pericardial mesothelioma only accounts for 1% of total cases. Standardly treated with surgery and chemotherapy. Because the disease is located on the heart, surgery can be considered risky. Symptoms of pericardial mesothelioma include unexplained and persistent chest pain, shortness of breath, coughing, or chest palpitations. Heart murmurs and irregular heartbeats may also come as symptoms.

Testicular Mesothelioma

It is the rarest type as there have only been a few hundred diagnosed cases in the U.S. Testicular mesothelioma typically develops in the tunica vaginalis testis, or the lining of the testes. Typically involving multimodal therapy including surgery, chemotherapy, and radiation therapy. This cancer is rare, so the symptoms are harder to determine. Because of its rarity, testicular mesothelioma is often mistaken for a hernia or other illness. The most common symptom among patients is painless lumps on the scrotum.

Types of Mesothelioma Cells

Epithelioid

Epitheloid cells are the most common cell type and the easiest to identify as they account for around 60% of cases. Generally easier to remove through surgery, this type of cell may give patients a better prognosis. The median survival rate for cancer with epithelioid cells is 18-24 months.

Fibrous Sarcomatoid

This cell type is often more aggressive and spreads faster, accounting for 25% of cases. The aggression in this form of mesothelioma results in a poorer prognosis. Patients with fibrous sarcomatoid cells have a median prognosis of 4-6 months.

Biphasic

A biphasic cell is a mixture of the others, fibrous sarcomatoid and epithelioid. These cells make up 15% of mesothelioma cases and are the least common cell form. This type of cell is difficult to treat, resulting in a median survival rate of 10-15 months.

Mesothelioma Stages

The prognosis for all types of this cancer is poor. Many people with this cancer learn of their illness after it has metastasized to other organs, lymph nodes, or bones.

The stage of cancer describes the tumors’ location, size, and whether malignant or not. Malignant cells mean that the cancerous cells can invade and destroy nearby tissues and spread to other body parts.

Cancers, like mesothelioma, are staged from I (1) to IV (4), with lower numbers representing an earlier stage. Although, the stages located in the chest are different from stages in the abdomen and the heart.

Stage I

Cancerous cells are found in the pleura surrounding one lung on one side of the body. In this stage, the cancerous cells have not spread to the other side of the body or any other lymph nodes or organs. During Stage I there are no or few symptoms. If caught during this time, there may be curative treatment and will result in a better prognosis.

Stage Ia

Cells containing cancer are found in the outer layer of the pleura, parietal pleura, surrounding one lung on one side of the body. In this substage, the cancer has likely not spread to other organs or body parts.

Stage Ib

Cancerous cells are located in the innermost layer of the pleura, visceral pleura, surrounding one lung on one side of the body. Cancer has not spread to other organs during this time but has begun to affect nearby tissues.

Stage II

During the second stage, cells are located on both layers of the pleura but only one lung. The masses may have increased in size and metastasized to nearby diaphragm muscles of lung tissues. During this time, a few symptoms will likely appear, but many mistake these for other illnesses. The prognosis for Stage II is fair and there is potential for curative treatment.

Stage III

In Stage III, tumors will likely have spread to the chest wall, lymph nodes, or the pericardium, the layer of tissue surrounding the heart. The prognosis for this stage is poor as the symptoms are likely worse. Although the prognosis is not great, the tumors may be small enough to remove through surgery or another palliative treatment option.

Stage IV

Tumors are larger and have spread throughout the body parts during Stage IV. Surgery is no longer an option for treatment during this stage, but palliative care may still be a possibility. During this time, the symptoms and prognosis are the worst.

Some forms, such as peritoneal and pericardial, are too rare to have established a staging system. Even though they do not have staging systems, other types of mesothelioma may be discussed using the staging system used above.

Mesothelioma Primary Treatment Options

Many patients wonder if this cancer is curable through treatment. Even if caught early on, mesothelioma is difficult to treat, and tumors grow in multiples and spread quickly to surrounding tissues. There are several factors a doctor may consider when developing a treatment plan for the individual patient. These factors include the patient’s:

  • Location of disease (peritoneum, pericardium, or pleural mesothelioma)
  • Stage of mesothelioma
  • Overall health
  • History of prior treatment

Three primary modes of treatment have been tested and developed, including surgery, chemotherapy, and radiation. Multimodal therapy may use these treatments alone or in conjunction with one another in different amounts and intervals.

Surgery

A doctor may recommend surgery to remove the tumor in its entirety. The surgeon will remove the cancerous tumor by making an incision and removing the affected tissue with a surgical tool. If unable to remove all the tumors, chemotherapy or radiation may be recommended to help diminish the affected areas.

Chemotherapy

Medical professionals utilize chemotherapy to administer anti-cancer medications by injecting them into the body. Depending on the location and stages of the tumor, doctors may choose to regulate the drug in different ways. The two most common methods are intravenous and intramuscular, which involves the doctor injecting the medications through a vein or muscle.

Radiation

Doctors utilize radiation when using high-energy x-rays to attack tumors deep within the body. There are two main types of radiation treatment – external beam radiation therapy (EBRT) and brachytherapy.

Targeted Therapy

Targeted therapy targets specific cells or body parts, unlike other treatment options which affect all cells, even healthy ones. The most common type of targeted treatment that doctors utilize is immunotherapy. This type of treatment is newer than other mesothelioma therapy and has become a more common inpatient treatment.

Finding Support and Mesothelioma Resources

The mental health effects of a cancer diagnosis can be detrimental for those diagnosed and the people in their life. Therefore, support groups and resources may benefit those who need assistance coping with grief, handling legal challenges, or keeping up a household.

Financial and Legal Options

Because many people were unknowingly exposed to asbestos and did not naturally develop mesothelioma, there is a reason for legal action. Laws and regulations, like workers’ compensation, protect people who fall ill from exposure while on the job.

By bringing legal action against those responsible, the patient or family may receive financial compensation to cover treatment costs or cases of wrongful death. Patients and their families have several legal options:

  • Asbestos Settlements
  • Asbestos Trust Funds
  • Class Action Lawsuits
  • Workers’ Compensation
  • Wrongful Death Claims

Support

Mesothelioma can extend beyond a patient’s physical health, affecting their mental health, as well as those around them. Several support resources include support groups, lodging programs, information call centers, and rides to treatments. Exploring different groups such as grief, legal, and similar organizations may be beneficial to the patient and provide support to family and friends. Explore your options with a guide provided by Lung Cancer Center.