Basic Facts About Mesothelioma

v  Mesothelioma is a primary tumour arising from the surface lining of the pleura(80% of cases) or peritoneum(20% of cases).

v  About three-fourths of pleural mesothelioma cases are diffuse(usually malignant) while the remaining one-fourth are localized(usually benign).

v  Three quarters of cases of mesothelioma are seen in men while women account for the remaining one quarter.

v  Numerous studies have confirmed the association of malignant mesothelioma with exposure to asbestos(especially the crocidolite form).

v  The lifetime risk of all asbestos workers coming down with malignant pleural mesothelioma is as high as 10%.

v  About 60-80% of patients with malignant mesothelioma report a history of known exposure to asbestos.

v  The latency period between exposure and onset of symptoms is 20-50 years.

v  Workers get exposed to asbestos in the mining,milling and manufacturing industries.Other sectors/products with high risks of exposure include:shipyard work,insulation,brake linings,building construction and demolition,roofing materials,asbestos pipes,textiles,paints,tiles,gaskets and a host of other products that contain asbestos.

v  Although cigarette smoking significantly increases the risk of lung cancer in asbestos workers and aggravates the symptoms of asbestosis,there is no association between smoking and mesothelioma.

v  The mean age of onset of symptoms of malignant pleural mesothelioma is 60 years.Symptoms include the gradual(not easily noticed) onset of shortness of breath,chest pain and weight loss.

v  Pleural mesothelioma usually affects only one lung with up to 60% of cases affecting the right lung.Only 5% of cases involve both lungs.

v  Treatment include surgery,chemotherapy,radiotherapy and a combination of methods.However,treatments are generally unsuccessful.

v  Prognosis is poor.Most patients die of respiratory failure and complications arising from metastasis.

v  The mean survival time from onset of symptoms range from four to sixteen months.Survival up to five years is less than five percent.

Early Mesothelioma Symptoms

Mesothelioma is a type of cancer that is almost exclusively associated with inhalation of asbestos fibers.Asbestos itself is a natural mineral that is very resistant to heat and corrosion and was widely used in the past and even up to the present in some countries especially many developing countries,in the construction and fireproofing industries among many other uses.Because of the long periods(latency period) between exposure and development of disease,it is usually difficult to diagnose the condition early enough.This leads to late diagnosis of mesothelioma in most patients with a very grave prognosis or outcome.

The most common form of mesothelioma is pleural mesothelioma.The pleura is the outer lining of the lungs and internal chest wall.The two most important early symptoms of pleural mesothelioma are chest pain and difficulty in breathing.They are a direct result of pleural effusion(build up of fluid in the chest) which can be seen in up to 90% of patients.Other early warning signs include dry cough or wheezing,fatigue,tightness in the chest and weight loss.

Another type of mesothelioma is peritoneal mesothelioma.The peritoneum is the inner lining of the abdominal wall.The most common early symptoms of peritoneal mesothelioma are abdominal pain,followed by abdominal enlargement and tenderness.There is also loss of appetite resulting in weight loss.

There is also pericardial mesothelioma.The pericardium is the outer covering of the heart.The most common symptoms here are chest pain and difficulty in breathing.They are as a result of the thickening of the pericardium.

For testicular mesothelioma,which is very rare,the most important and consistent symptom is a lump in the testis.

Because of the long latency period from exposure to asbestos to development of mesothelioma(mean latency for men is 48 years while for women it is 53 years),it is important that people at most risk of developing the disease should present themselves for regular screening.Usually onset of symptoms is  gradual and more often than not are attributed to less serious conditions.Many patints also have other respiratory diseases and the onset of mesothelioma is often misinterpreted as a worsening of the existing condition.Early diagnosis leads to a better prognosis and should be taken seriously by people with a history of exposure to asbestos whether or not they have any symptoms of mesothelioma.

Mesothelioma Symptoms

Mesothelioma is a rare form of cancer that is almost exclusively associated with direct or indirect exposure to asbestos.It develops from abnormal cancerous cells in the mesothelium which is the protective lining that covers many of the internal organs of the body.

The most common type of mesothelioma is pleural mesothelioma(the pleura is the outer lining of the lungs and internal chest wall).There is also peritoneal mesothelioma(the peritoneum lines the abdominal cavity).It can also affect the pericardium(the outer lining of the heart) or the tunica vaginalis(the sac that surrounds the testis).

 Mesothelioma symptoms may not appear until 20-50 years or more after exposure to asbestos.The most vulnerable group are workers in the asbestos and construction industries and their family members who come in contact with their contaminated clothing.Symptoms depend on the site or location of disease .

For mesothelioma that affects the pleura,the following symptoms may be present:

• ·        Shortness of breath.
• ·        Heavy feeling in the chest region.

These two are the most common symptoms of pleural mesothelioma and are a result of pleural effusion(build up of fluid in the chest area).They should be taken seriously especially if the individual has a history of exposure to asbestos.Other symptoms include:

• ·        Unexplained weight loss.
• ·        Chest wall pain.
• ·        Difficulty swallowing.
• ·        Cough or wheezing.
• ·        Anaemia and fatigue.
• ·        Blood in the sputum(haemoptysis)

In severe cases,there may be tumour masses,collapse of the lungs and spread to other parts of the body(metastasis).

Mesothelioma symptoms in cases of peritoneal involvement are often not detectable until in the late stages of the disease.They include:

• ·        Abdominal pain.
• ·        Weight loss.
• ·        A mass in the abdomen.
• ·        Ascites(a build up of fluid in the abdominal cavity).
• ·        Bowel obstruction.
• ·        Anaemia.

In severe cases,there may be blood clots in the veins,disseminated intravascular coagulation,a disorder characterized by bleeding in many body organs,jaundice( yellowing of the eyes and skin),hypoglycaemia(low blood sugar level),pleural effusion,pulmonary emboli(blood clots in the arteries of the lungs),severe ascites.

As with other types of cancer,early diagnosis offers better prognosis.It is therefore imperative that persons with history of exposure to asbestos whether as a factory worker or a family member of a worker in the asbestos and construction industries should present themselves for regular screening,whether or not they are experiencing any discomfort in the chest area.