Facts about Pleural Mesothelioma

Mesothelioma is the commonest primary tumor of the pleura. There are two main types:
1-the localized mesothelioma(bening and malignant types)
2-the diffuse malignant mesothelioma

Causes
There is a strong correlation between asbestos exposure and the development of mesothelioma, although a history of exposure is not always obtainable in patients who have mesothelioma. There are 2 types of asbestos fibres based on crystalline structure; a-serpentine (chrysolite) and b-amphibole. Included within the amphibole are amosite, tremolte, crocidolite and anthophyllite. The most harmful is the crocidolite or better known as "blue asbestos".

1-i-Localised Bening Mesothelioma

These characteristically arise from the inner layer of the pleura
Symptoms and signs:
-chest pain
-shortness of breath
-most of the times there are no symptoms (asymptomatic), these tumors are usually discovered on routine chest x-ray
-hypoglycaemia (low blood sugar) is sometimes associated

Treatment
Surgery is the main treatment, the tumor is removed by the surgeon and reccurence is rare and when it happens transition to malignant form of tumor should be suspected.

1-ii-Localised Malignant Mesothelioma

Symptoms and Signs:
-chest pain
-cough
-fever
-shortness of breath
Treatment
Surgery is also the treatment of choice, although prognosis is very poor.

2-Diffuse Malignant Mesothelioma

This type of mesothelioma can arise from any part of the pleura and often extend into the peritoneum as well as into the ribs and chest wall (peritoneal mesothelioma and pericardial mesothelioma). It also spreads commonly to the liver, brain and adrenal glands. Histologically malignant mesothelioma have both fibrous (sarcomatous mesothelioma) and epithelial(papillary) components.

Investigations
-CT scan of the chest is extremely useful in diagnosing the extent of the tumor.
-Needle biopsy (the surgeon inserts a special needle into the pleura to take samples of the tumor which is taken to the laboratory to see under the microscope) of the pleura is a must.
-Pleural fluid is aspirated and taken to the lab for microsopic examination.

Staging of Malignant Pleural Mesothelioma

Stage 1:Involvement of ipsilateral pleura and lungs (affecting just one lung either left or right lung)

Stage 2-Invlovement of chest wall, mediastinum (structure at the middle of the heart), pericardium or contralateral (opposite side)pleura

Stage 3-Distant blood spread into other organs eg brain, adrenals

Treatment
Treatment is discouragingly ineffective and survival rarely longer than 2 years with an average of 10-14 months. In selected cases with stage 1 a radical sugery-pleuropneumonectomy may be effective, but long term survival is rare. Primary radiation therapy may be used also. Combination chemotherapy using either single agent or combination protocols have also been used but the outcome remains dismal.