Mesotheliomas are usually of three different cell types: 1) epithelial cell type, which has the most favorable prognosis; 2) fibrosarcomatous cell type, which has the most negative prognosis and 3) mixed cell type, which has an intermediate prognosis.

Physicians use imaging studies such as MRI scans, x-rays and CT scans to classify the cancer's spread (or “stage”). Staging is one of the most important steps; it allows doctors to determine a patient’s course of treatment and gives them a better understanding of the patient's prognosis. Pleural mesothelioma is the only mesothelioma for which a staging classification exists. That form of the cancer occurs most frequently and has been widely studied.

The Butchart system is the most common staging system for mesothelioma. This staging system, which is based primarily on the extent of the primary tumor mass, classifies mesotheliomas as Stages I through IV. The following provides information on each stage and the most often associated treatment:

Localized Malignant Mesothelioma

Stage I: This cancer is located in the right or left pleura. It may also be found in the lung, diaphragm or pericardium.

When the cancer is found only in the chest or abdomen, surgery is a common option to remove part of the pleura and the surrounding tissue. When the cancer is located in a larger part of the pleura, one of the following may be performed:

• External beam radiation therapy to relieve symptoms.
• A clinical trial of surgery followed by chemotherapy given inside the chest.
• A clinical trial of surgery, radiation therapy, and/or chemotherapy.
• Surgery to remove the pleura and the tissue near it to relieve symptoms, with or without radiation therapy after surgery.
• Surgery to remove sections of the pleura, the lung, part of the diaphragm, and part of the lining around the heart.

Advanced Malignant Mesothelioma

Stage II: In this classification, the mesothelioma has spread beyond the lining of the chest wall or involves the esophagus, heart or pleura on both sides. Mesothelioma may also be found in the lymph nodes of the chest.

Stage III: Under this classification, the cancer has spread into the chest wall, penetrated the diaphragm, and is present in the center of the chest heart and abdominal lining and into lymph nodes beyond the chest.

Stage IV: There is evidence that mesothelioma has spread through the bloodstream to distant tissues and organs (distant metastases).

Treating Advanced Mesothelioma

1. Draining of fluid in the chest or abdomen (thoracentesis or paracentesis) to reduce discomfort. Drugs also may be put into the chest or abdomen to prevent further collection of fluid.
2. Surgery to relieve symptoms.
3. Radiation therapy to relieve symptoms.
4. Chemotherapy.
5. A clinical trial of surgery, radiation therapy, and chemotherapy
6. Chemotherapy given in the chest or abdomen.

The TNM system (Tumor lymph Nodes Metastasis) is another, more detailed and precise staging system developed by the American Joint Committee on Cancer (AJCC). There are some minor differences between the AJCC TNM staging system and the Butchart system. The Butchart system remains the most commonly used staging method.

Traditional Treatments

Currently, no known cure exists for malignant mesothelioma. Patients have several treatment options. The most common options are surgery, chemotherapy and radiation therapy. In many cases, doctors will combine two or more courses of treatment for the maximum likelihood of success. This “multimodal” approach holds the most promise for survival of malignant mesothelioma patients. Trimodality therapy uses all three of these modalities and is considered the most effective aggressive approach. Each patient's course of treatment depends on the location of the disease, the stage of the disease, as well as the patient's age, overall health and personal preferences for treatment.

Surgery

The type of mesothelioma a patient has and the stage of the cancer will determine the type of surgery used to treat it. Mesothelioma tumors are typically large and difficult to completely remove. For that reason, surgery is often combined with other cancer treatments to ensure the best results in destroying the tumor.

Chemotherapy

Chemotherapy may be given as the primary treatment to mesothelioma, or it may be used in addition to surgery. In chemotherapy, drugs are used to eradicate cancer cells. Chemotherapy is referred to as systemic treatment. The drug is introduced into the bloodstream and travels throughout the body where it kills cancer cells. The drugs may be in pill form or injected through a needle. Researchers are also studying the delivery of chemotherapy directly into the chest or abdomen (intrapleural or intraperitoneal delivery).

To effectively treat mesothelioma, multiple drugs may be used. Depending on the drugs, the amount taken and the treatment period, there may be side effects. The most widely used single chemotherapy drug has historically been doxorubicin. Newer drugs, including gemcitabine, cisplatin, carboplatin, epirubicin, cyclophosphamide, ifosfamide, vinorelbine, paclitaxel, and methotrexate, are often preferred and given in different combinations.

The University of Chicago Cancer Research Center recently released the results of a yearlong clinical trial of Pemetrexed Disodium (Alimta). The study showed positive results when Alimta, which has the ability to reduce tumors, prolong survival and reduce pain, was used with vitamins and the traditional chemotherapy drug, Cisplatin, for treating malignant pleural mesothelioma.

Several new experimental treatments are being tested as a way to enhance the immune system's ability to combat malignant mesothelioma. These include gene therapy and the use of cytokine proteins such as interferons and interleukins. These treatments are also being tested in combination with chemotherapy and other treatments.

Radiation therapy

Radiation therapy uses high-energy x-rays help to destroy cancer cells and shrink tumors. The radiation may come from a machine (external radiation) or from radioactive materials placed directly in or around cancer cells through thin plastic tubes (internal or implant radiation). Radiation treatment may be accompanied by side effects, but most of these will go away after a short while.

In pleural mesothelioma, it is difficult to irradiate tumor tissue successfully without injuring nearby organs such as the lungs, heart or liver. However, radiation therapy can be an effective method for relieving pain in certain situations.

Non-Traditional Treatments

Photodynamic Therapy

Photodynamic therapy destroys cancer cells by using the energy from light and may also be effective when combined with surgery. In the procedure, the patient receives a photosensitizer (a drug which makes cells sensitive to specific wavelengths of light) which collects in cancerous cells but not in healthy cells. Once the cells have been sensitized, fiber optic cables are placed in the body (usually through open-chest surgery) so that the correct frequency of light can be focused on the tumor. This causes the photosensitizer drug to produce a toxic oxygen molecule, killing the cancer cell. The treatment is in the experimental stage for mesothelioma, but it has shown promise in treating other cancers.

Gene Therapy

This new treatment is currently in clinical trails. Gene therapy allows treatment to target tumors, rather than destroying healthy cells which is the downside of traditional chemotherapy. In gene therapy, cancer is treated by altering genetic defects that allow a tumor to develop. A “suicide gene” is inserted directly into the tumor, making the cells sensitive to a normally ineffectual drug. The drug is then administered to the newly sensitive cancer cell, destroying those cells while leaving the healthy cells unharmed.

Immunotherapy

Immunotherapy (or biological therapy) treats cancer by using the body’s own immune system to battle cancer cells. Another name often applies to this therapy, biological response modifiers (BRMs). Promising clinical studies are under way.

In addition to traditional forms of treatment, some cancer patients have turned to alternative medicine’s healing philosophies and spiritual approach for living with the disease.