Mesothelioma is a very rare form cancer inflicting some people. Not all countries report cases of the disease. But did you know that there are reported cases of mesothelioma and granuloma among feline creatures?

Feline granuloma and mesothelioma are much more rare than human mesothelioma. However, experts and researchers are turning more curious and interested about the subject as years go by. That is because there are too many questions and factors that must be resolved and answered about feline cases of granuloma and mesothelioma.

But first, it would be better if you would have a briefer of what granuloma and mesothelioma are. For sure, your interest and curiosity would be further aroused if you find out the known causes for the disease. You might ask the question, ‘How do cats acquire such ailments?’

Granuloma and mesothelioma

In medical terms, granuloma and mesothelioma are two different terms and diseases for living organisms like mammals. To make it simple, there is a clear distinction between the two. Granuloma is non-cancerous or is often described as benign, while mesothelioma in contrast is most of the time malignant, or cancerous, and would often lead to the death of the individual.

While both the diseases affect tissues within the internal organs of the body, there is still basic differences. One, granuloma is considered a form of a serious infection and can easily be treated. Second, granuloma is not as severe as mesothelioma.

For its part, mesothelioma is often malignant and death-causing. Although prognosis, or rate or chances of survival, is possible, most of the reported cases end up in death of the diagnosed patient.

To understand mesothelioma better, try to comprehend its causes and other problems associated with it.

Mesothelioma, in focus

Mesothelioma is a rare form of cancer that occurs in the mesothelial tissue or the sac lining in the chest. Researches have found that asbestos when exposed to air disintegrates into very miniscule fibers that can be inhaled without people being aware of it.

Once the asbestos fibers reach the lungs, they enter the mesothelila tissues and accumulate. The process would not create significant adverse results overnight. Experts estimate that it should take about two months of exposure before a person accumulates sufficient asbestos fibers to develop a tumor that would eventually lead to mesothelioma.

Another striking fact about mesothelioma is that it does not occur in an asbestos-exposed person until about 20 to 30 years after the exposure. That is the main reason why on the average, mesothelioma patients are aged about 50 years to 70 years.

Thus, people exposed to asbestos would not abruptly feel and bear the effects of exposure to the substance until a significant amount of time. That way, in the past, people diagnosed with mesothelioma had not readily linked the disease to their possible exposure to asbestos.

Mesothelioma in cats

Feline mesothelioma, therefore, is another case. Is feline mesothelioma caused by asbestos exposure? If that is so, then the owner of the cat is also at risk of developing mesothelioma in the future because he might also be of exposed to the substance.

In cats, mesothelioma could be disgnosed of the cat is aged seven to ten years. Most common symptom is drastic and sudden loss in weight.

Veterinarians are still researching on what may cause feline mesothelioma and granuloma, although some suggest that it may be caused by substances in cat litter boxes. The dusts in the litter boxes may contain little amount of asbestos, although this ideas is still to be verified.

Often, cats diagnosed with feline mesothelioma or feline granuloma end up dying. That is because animals are hard to treat because of the complexity of their structures. Many vets also ask cat owners with to just let consent for biopsy so the cat could contribute well to current research about feline mesothelioma and granuloma.

Euthanasia is not an issue among sick animals, although animal rights advocates could openly oppose the idea. If your cat is diagnosed with mesothelioma or granuloma and there is only less chance of prognosis, make the decision to donate the cat instead for biopsy. That way, at least the cat died for good purposes.

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.