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Before your surgery you will need to take tests to make sure you are fit enough to make a full recovery.
• Blood tests to check your
general health
• A CT (CAT)
and MRI scan
• Tests to see
how well your lungs are working,
called lung function
tests
• Lung perfusion scan
• An echocardiogram
The lung function tests:
When considering surgery, the patient's overall health status should be evaluated in detail. Tests should be performed to ensure that the cancer nas not metastaticized (spread to distant organs) and to evaluate the patient's overall lung and heart function. Lung capacity and function often is reduced in patients with pleural Mesothelioma for several reasons. Often the pleural effusion (fluid collection) and the mass of the tumor caused by Mesothelioma can press against the lungs. Additionally, the gestation period of the disease may well have taken decades and the patient's lung function may have decreased, as a natural part of the aging process. Smokers often have had further decreases in lung function and capacity.
Lung tests are vital before this type of treatment. Your doctor needs to be sure that your lungs are working well enough for you to recover well from your surgery. Lung function tests measure how well your lungs take in oxygen. There are different, specific types of lung function test. The simplest involves you breathing out as hard as you can into a tube attached to a machine. This measures how much air your lungs can take in.
During another type of lung function test, you may have to breathe in a very small amount of radioactive gas. This will not harm you and carries no risks at all. It causes your airways to show up clearly on the scan. The radioactivity involved is miniscule and goes away within a couple of hours.
Finally, a lung perfusion tests look at the blood supply to the lungs. This means having a small radioactive injection. Again, this is harmless. It allows the specialist to see the blood flowing to your lungs. These 2 tests can be done together and only take about 20 minutes.
An echocardiogram takes a picture of your heart using sound. It is painless and only takes about half an hour. This procedure can show if the cancer has spread into the heart muscle. Mesothelioma can sometimes spread from the lining of the lung to the cavity at the centre of the chest ( the mediastinum), which contains the heart.
Surgery for malignant Mesothelioma is intended to acheive long-term control (described as aggressive surgery) or to give immediate relief from symptoms (define as a palliative procedure).
Aggressive Surgery - The procedure known as Extrapleural Pneumonectomy involves the removal of the pleura, the lung, including the diaphragm and the pericardium. This very aggressive, complicated surgery removes as much of the tumorous tissue as possible. Not all hospitals will perform this procedure because of its complexity, associated costs and the high risk of death within 30 days. Extrapleural Pneumonectomy is usually performed only in younger patients in the first stage of the disease's development, whose overall health is good. Prospective patients are evaluated to determine their ability to survive the surgery and surgeons at differ in their criteria for selecting candidates. It is important to check with each doctor to determine the standards that will be applied.
Palliative Procedures - When Mesothelioma is well-advanced, palliative procedures may alleviate symptoms like shortness of breath, are caused by effusion (meaning fluid collection) or the pressure of the tumor compressing the lung. This approach is not intended as a curative effort.
Another treatment for effusion-related symptoms is Thoracentesis, in which a needle is inserted into the chest to drain the fluid thereby relieving shortness of breath and discomfort. A talc-based powder may be introduced into the pleura to prevent a recurrence of the effusion. A nearly identical procedure may be used to treat ascites (fluid collection) in peritoneal region.
Pleurectal decortication involves the surgical removal of the pleura. It can reduce pain caused by the tumor mass or as a prophilactic measure to prevent the recurrence of pleural effusion. In cases of peritoneal Mesothelioma, surgery intended to provide relief from symptoms such as recurrent ascites or bowel obstructions. As with pleural Mesothelioma, complete surgical removal of the entire tumor is not usually possible.
Extrapleural pneumonectomy
Pneumonectomy is the surgical removal of an complete lung and is generally performed as a cancer treatment. There are two types of pneumonectomy: the "traditional" pneumonectomy, in which only the diseased lung is removed and by contrast the "extrapleural" pneumonectomy, the pneumonectomy frequently performed in cases of malignant Mesothelioma. Because Malignant mesothelioma is a cancer of the pleura (the membrane lining the lungs) and therefore the pneumonectomy required to treat this disease, must remove not only the diseased lung, but part of the pericardium (the membrane covering the heart), a portion of the diaphragm and the parietal pleura (the membrane lining the chest cavity) on the same side of the chest.
An extrapleural pneumonectomy is the preferred option when a tumor is located in the middle of the lung and has involved a significant portion of the pulmonary artery or veins. Because the surgery is risky and reduces by half the patient's breathing capacity, surgeons usually consider it as a last resort and will usually first consider a pleurectomy.
A Pleurectomy is a more complicated procedure, but spares the lung, involving only the removal of the pleura. Which option is chosen depends on many factors, including the stage of the tumor.
It is unclear if extra-pleural pneumonectomy provides significantly greater benefits than pleurectomy or if either approach is significantly more effective than non-surgical options.
Pleurectomy may be technically more difficult and complex than the extrapleural pneumonectomy. However, the mortality of pleurectomy is more favorable (1.5%-5% when performed by an experienced surgeon) and though extrapleural pneumonectomy may appear to be more effective in removing more of the tumor by the en-bloc resection and when performed early enough, pleurectomy is equally effective. In later stage mesothelioma, when there is a tumor invasion of the lung parenchyma, pleurectomy is no longer an available option.
A recent study designed to compare the effectiveness of pleurectomy, and extra-pleural pneumonectomy revealed that neither was more effective than the other in prolonging survival rates. Instead, other factors seemed to determine how long people survived after treatment. These factors included the stage and cell type of the tumor, the gender of the patient, and the specific choice of treatment(s) given in conjunction with the surgery.
Pleurectomy can provide some symptomatic relief and sometimes the bulk of the tumor can be removed. It is frequently used in combination with other treatments, but its value has been shown to be very limited if the tumor is near any vital organs. Additionally, it is a complex surgical procedure, beyond the skills of most surgeons. Generally, patients are referred to centers specializing in such treatments. Many of these centers also focus on other forms of mesothelioma treatment, either standalone or in combination (multi-modal therapy).
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