The first step in detecting pleural mesothelioma is, typically, a
chest x-ray or CT scan. This is often followed by a bronchoscopy, using
a viewing scope to look inside the lungs.
The actual diagnosis usually requires obtaining a piece of tissue
through a biopsy. This could be a needle biopsy, an open biopsy, or
through a tube with a camera (thoracoscopy or chest scope.) If an
abnormality is seen through the camera then a tissue sample can be taken
at the same time, using the same tube. This is a hospital procedure that
requires anesthesia, but is not usually painful. The tissue sample is
tested by a pathologist.
Fluid build-up from the pleural effusion can generally be seen on a
chest x-ray and heard during a physical examination, but a firm
diagnosis of mesothelioma can only be made through a biopsy and
pathological testing.
The spread of the tumor over the pleura causes pleural thickening.
This can reduce the flexibility of the pleura and encase the lungs in an
increasingly restrictive girdle. With the lungs restricted, they get
smaller and less functional, and breathing becomes more difficult. At
first a person with mesothelioma may be breathless only when he or she
exercises, but as lung function drops, he or she can become short of
breath even while resting.
The tumor spreads by direct invasion of surrounding tissue. As it
spreads inward it can compress the lungs. As the tumor spreads outward
it can invade the chest wall and ribs, and this can be extremely
painful.