New Mesothelioma Treatments

New Treatments for Mesothelioma

Current research focuses on causes, prevention, and improving accuracy of diagnosis and effectiveness of mesothelioma treatments. In spite of advances in research, there is still a great deal to be learned. Mesothelioma treatments that combine surgery, radiation therapy, and chemotherapy, called multimodality therapy, are now being studied. These may provide the most promising option for some patients. New chemotherapy drugs and other types of mesothelioma treatments are the subjects of current clinical trials.


Gene Therapy

A new approach to mesothelioma treatment is gene therapy, using special viruses that have been modified in the laboratory. In gene therapy, the modified virus is injected into the pleural (chest) space and infects the mesothelioma cells. The virus injects a gene into the tumor that heightens the effects of a mesothelioma-fighting drug.


Immunotherapy

Immunotherapy - treatment methods that fight mesothelioma through the body's immune system - is being evaluated in clinical trials. With immunotherapy, substances called biological response modifiers (BRMs) may be made by the body or in a laboratory. BRMs are used to boost, direct, or restore the body's natural ability to defend itself against cancer. This type of mesothelioma treatment is also called biologic therapy or biotherapy.


Intensity Modulated Radiation Therapy (IMRT)

IMRT is a new radiotherapy technique that has proven to be effective in controlling localized malignant mesothelioma. IMRT mesothelioma treatment delivers high doses of radiation to mesothelioma tumors, regardless of their size or shape. Precise targeting of radiation makes IMRT a preferred mesothelioma treatment over standard radiotherapy, in which the healthy tissue surrounding the tumor may also be exposed to high levels of radiation. Tumors that would once have been considered untreatable because of their proximity to vital organs can now be treated using IMRT.


Chemotherapy

Chemotherapy is the use of cancer-fighting drugs in the treatment of mesothelioma. Although chemotherapy has long been used in the treatment of mesothelioma, the search for safer and more effective chemotherapy drugs is ongoing.

Alimta is the brand name for one such drug, chemically similar to folic acid, which is being tested for the treatment of mesothelioma. Alimta is used alone for the treatment of locally advanced or metastatic lung cancers whose growth has not been slowed by traditional chemotherapy treatments. When used in conjunction with cisplatin, Alimta is the only agent approved by the Food and Drug Administration for specific use in combating malignant pleural mesothelioma.

Anti-angiogenesis drugs are relatively new mesothelioma treatments that have been successful in shrinking and killing cancerous cells in animals. Although the success of anti-angiogenesis drugs in humans has not been proven, they are expected to yield similar results. Veglin is an anti-angiogenesis drug designed to target a wide range of cancers, including malignant mesothelioma.

Mesothelioma - Chemotherapy Treatment

Mesothelioma is a malignant type of cancer that is caused by being exposed to asbestos. The cancerous cells are developed in a protective lining that covers internal organs in the body called mesothelium. The most common site of mesothelioma is in the outer lining of the chest wall and lungs called the pleura. It can also occur in the lining of abdominal, peritoneum cavity, or the sac that is around the heart, pericardium.
It is found that most people that develop mesothelioma have been exposed to asbestos particles at some time in their life.

Mesothelioma is an aggressive type of cancer and Doctors want to treat it as soon as possible and with aggressive treatment. One of the treatments includes Chemotherapy and its strong drugs that can destroy the cancer cells.
Chemotherapy is an option for those patients that are not able to go through a surgical procedure. The Doctor determines if the patient is a surgical candidate or not. Chemotherapy has been used since around the 1940's.
Using Chemotherapy for treatment of mesothelioma can be taken in pill form, intravenously, or if the cancer is in the pleural; it is injected directly into the lungs.

Chemotherapy treats the disease by using chemicals that kill the bad cancerous cells and also damages the good cells around the cancer area. There are a few types of chemotherapy treatments for mesothelioma besides the curative intent.
They are:

- Intensity Modulated Radiation Therapy
- Adjuvant chemotherapy- which means chemotherapy is used after a surgical technique and if the doctor feels there is a risk for recurrence of the cancer.
- Combined modality chemotherapy- this means chemotherapy is used in combination with radiation therapy or surgery.
- Neoadjuvant chemotherapy- referrs to being done prior to surgery to reduce the size of the tumor mass.
- Palliative chemotherapy- is used as a treatment to the symptoms of mesothelioma

There are side effects that come from chemotherapy treatment. Most Doctors tell the patients about these side effects that can come from this treatment. Most of the side effects will go away when the treatment has ended. These include:

- Weakening of the immune system
- Hair loss
- Nausea and vomiting
- Constipation
- Diarrhea
- Decrease in number of red blood cells
- Ototoxicity
- Nephrotoxicity
- Higher risk of cardiovascular disease
- Cardiotoxicity
- Hepatoxicity

The results of treating Mesothelioma with Chemotherapy can be good to stop the growth of the cancer and help shrink it, but unfortunately there is no cure for mesothelioma.

Mesothelioma Treatments

Mesothelioma treatment options depend on many internal factors such as: stage, location, and the patient’s age and desires. Important external factors to consider include the experience level of the oncologist with mesothelioma cases and whether or not a rural dweller would have to be transferred to a larger city for aggressive treatment or palliative care.

Patient survival rate is determined to be up to a year; while some leading cancer centers have reported life expectancy after diagnosis to be as much as five more years.

Screening

Imaging tests allow doctors to see a picture of the cancer site. These tests could include x-rays, CT scans (computed tomography), or MRI (magnetic resonance imaging).

New Screening Instrument: The Mesomark Test

The Food and Drug administration has just approved (January 2007) the world's first in-vitro test for mesothelioma. The Mesomark assay test, developed by Fujirebio Diagnostics is administered to patients diagnosed with biphasic or epithelioid mesothelioma by a simple blood test. The test measures proteins within the blood that reflect changes in the patient's tumor volume, a key factor for monitoring patient status and response to therapies.

Traditional Treatment Types

Surgery, removal of the entire lung and a part of the chest lining, the diaphragm and part of the sac surrounding the heart.

Thoracoscopy is the insertion of an endoscope which is a small narrow tube, containing a tiny cameria into the pleural cavity to look directly at the tumor. Pathologist’s perform a biopsy to collect a tissue. Often, chemical pleurodesis (draining fluid in the intrapleural space), can be accomplished during the same procedure.

Mediastinoscopy, another type of surgical incision is sometimes used to stage the extent of disease when enlarged nodes are seen using imaging techniques.

Laproscopy is used in mesothelioma patients when imaging techniques suggest that the tumor has penetrated through the diaphragm. This information is important in evaluating a patient for potential pleurectomy or extrapleural pneumonectomy.

Radiation Therapy (using high-dose x-rays or other high-energy rays to kill cancer cells.

Radiation - Although mesothelioma tumors are highly resistant to radiotherapy, these treatments are sometimes used to relieve symptoms arising from tumor growth, such as obstruction of a major blood vessel.

Radiotherapy is commonly applied to the sites of chest drain insertion, in order to prevent the growth of the tumor along the track in the chest wall.

Chemotherapy – is used to stop the cancer cells from growing and dividing.

Immunotherapy: Heated Intraoperative Intraperitoneal Chemotherapy requires the removal as much of the tumor as possible followed by the direct administration of a heated between (40 and 48°C) chemotherapy agent, into the abdomen for 60 to 120 minutes and then drained.

Palliative Procedures

Pleuroperitoneal Shunt is a procedure where a catheter is placed under the skin from the pleural to the peritoneal cavity. This procedure raising concerns as the catheter can cause damage by embedding itself into the abdomen.

Pleurectomy, a palliative procedure, may be performed when more extensive surgery is not an option. The procedure does not effectively remove all tumors. It is considered the most effective means of controlling pleural effusion (fluid buildup) in cases where the lung's expansion is restricted by the mesothelioma.

Potentially Curative Procedures

These procedures are performed with "curative intent".

Pleurectomy/Decortication is usually performed on patients with early stage pleural mesothelioma disease (Stage I and selected Stage II), and attempts to remove all gross tumor.

Extrapleural Pneumonectomy is surgery to remove a diseased lung, part of the pericardium, part of the diaphragm and part of the parietal pleura. This type of surgery is used most often to treat malignant mesothelioma and is combined with traditional chemotherapy and/or radiation, gene therapy, immunotherapy or photodynamic therapy.

Cytoreductive Surgery removes visible tumors in the peritoneal cavity. The remaining cancer cells are treated by Intra-Peritoneal Hyperthermic (heated) Chemotherapy (IPHC) and then delivered to the abdominal cavity.

New or Experimental Therapies

Gene Therapy: The best known tumor suppressor gene is called p53. If this gene is damaged or non existent oncogenes or cancer genes multiply at an abnormal rate. The main focus of gene therapy for mesothelioma involves injecting a virus that has been modified in the laboratory. The virus is injected into the pleural space in the chest, where mesothelioma develops as an attempt to kill the cancer cells.

Drug or Vaccine Therapy

Patients with mesothelioma have much higher levels of vascular endothelial growth factor (VEGF) a chemical controlling blood vessel than people with any other type of cancer. Trials are being conducted to see if VEGF can be blocked, thus stopping the growth of blood vessels feeding the mesothelioma tumors.

Bevacizumab is a drug vaccine currently in use. One trial recently reported that this drug may increase survival for patients with lung cancer. An American phase 2 trial tested bevacizumab for mesothelioma, in combination with chemotherapy drugs. Bevacizumab is still in the experimental phase and much larger trials are needed before we will know how effective it will be in treating mesothelioma and other types of cancers.

Photodynamic Therapy (PDT)

In Photodynamic therapy a drug called a photosensitizing agent is injected into the bloodstream and absorbed by the body's cells rendering the cells sensitive to light. When the area to be treated is exposed to laser light, the cells are killed. PDT has to be combined with surgery to treat patients in the early stages of mesothelioma. PDT is still in the trial stages and very experimental.

Clinical Trials and Eligibility

Clinical Trials provide research by using a sampling of people affected by the cancer. The National Cancer Institute states that the purpose of most listed clinical trials is to test new cancer treatments or new methods of diagnosing, screening for or preventing cancer.

Eligibility requirements for clinical trials are not the same; each study has specific guidelines for participation. Some trials allow participation after other treatments have failed, while others require that the patient did not have prior treatment. Choosing a clinical test should only be done after a medical consultation.

Prevention trials - study ways to reduce the risk, or chance, of developing cancer. Most prevention trials are conducted with healthy people who have not had cancer. These trials use drugs, vitamins or diet to reduce risk of cancer. Some trials are conducted with people who have had cancer and want to prevent the return of cancer (recurrence), or reduce the chance of developing a new type of cancer.

Screening Trials - study ways to detect cancer. They are often conducted to determine whether finding cancer before it causes symptoms decreases the chance of dying from the disease. These trials involve people who do not have any symptoms of cancer.

Diagnostic Cancer Trials - develops new tests or scans

Treatment Trials – studies new drugs or combinations of drugs; new ways of giving treatment, and new types of treatment

Quality of life trials explore ways to improve the comfort and quality of life of cancer patients and cancer survivors. These trials may study ways to help people who are experiencing nausea, vomiting, sleep disorders, depression, or other effects from cancer or its treatment.

Genetics Study Trials - are sometimes part of another cancer clinical trial. The genetics component of the trial may focus on how genetic makeup can affect detection, diagnosis, or response to cancer treatment.

Clinical trials are conducted in 4 phases:

Phase 1 trials look at whether a trial treatment drug is safe or has any harmful effects and attempts to establish the right dosage required.

Phase 2 trials look at the effectiveness of the treatment.

Phase 3 trials test a new treatment against the existing standard treatment. If it yields better results, it may become the new standard treatment.

Phase 4 trials are carried out after a drug has been licensed. They collect information about side effects, safety and the long term risks and benefits of a drug.

Ongoing research attempts to improve mesothelioma treatment options but clinical trials will not all result in new and better treatment. After testing, it may be discovered that the treatment being tested does not work, or that it has worse side affects than existing treatments. But, to researchers and doctors, and in the end for patients, it is crucial to keep this research going.