The diagnosis of mesothelioma is actually quite challenging.
It is often delayed, in fact. The patients will often present with somewhat non-specific symptoms such as chest pain or shortness of breath or even a cough, and they are found to have fluid outside of the lung but inside of the rib cage. And there are several processes that can cause this, and early on, the first steps to evaluate that are just draining that fluid out and sending it for sampling.
Unfortunately, the sensitivity of tests of that fluid to diagnose mesothelioma is not great, and so the diagnosis is frequently missed. So people will undergo repeated drainage of fluid and not get a diagnosis of cancer at all. Or if they are diagnosed with cancer, unfortunately there are some unique aspects to mesothelioma at a microscopic level that requires some expertise on the part of the pathologist or the person called a cytopathologist, who looks at cells, to evaluate.
In fact, with mesothelioma, it's often required that some tissue be evaluated, and that has a higher accuracy rate than just the fluid itself. And it really does require experience on the parts of the clinicians, a high index of suspicion on the part of the clinician evaluating the patient, and some expertise among the team--
the pathologists and cytopathologists who are looking at those samples.
