Mesothelioma’s tendency toward presenting symptoms that are easily mistaken for less serious illnesses (such as viral pneumonia) can create a diagnostic challenge for physicians. Further complicating the issue is that some people may never experience any symptoms at all.  Frequently, a protracted period of latency occurs between a person’s exposure to factors that contribute to mesothelioma and its development; this latency period can be as long as twenty or thirty years in some cases.  While the possibility exists for an obscuration or even complete lack of symptoms, there are certain factors that can be distinctly indicative of potential mesothelioma. 

Pleural Mesothelioma
In the case of pleural mesothelioma, which attacks the covering of the lungs, a person may experience bouts involving shortness of breath.  Physicians refer to this symptom as dyspnea; the person suffering from dyspnea feels that they are unable to get enough air into their lungs despite attempts at compensating.  Dyspnea can be accompanied by a persistent cough, and fluid may also accumulate in the lungs of a person with pleural mesothelioma, contributing to the patient’s shortness of breath and causing chest pains.  Chest pains and shortness of breath are the two most commonly presented symptoms by patients who eventually receive a mesothelioma diagnosis, and a fever may also be present.  For some patients, pains may be limited to the area under the rib cage, while others may experience pains that radiate to the upper abdomen, back, shoulder, and arm. 

Peritoneal Mesothelioma
With peritoneal mesothelioma, which involves the covering of organs in the abdominal area, a person may experience pain and swelling in the abdominal region due to an accumulation of fluid.  The abdomen may appear enlarged or distended, and tumor masses may be detected through visual examination.  Peritoneal mesothelioma can also lead to a bowel obstruction, which produces similar symptoms of abdominal pain and possibly diarrhea, nausea and vomiting, and/or constipation, depending on the location, severity, and timing of the obstruction.  The most common symptoms presented in patients with malignant peritoneal mesothelioma include tenderness of the abdomen, abdominal masses, sudden weight loss, and fluid retention in the abdominal area.

Pericardial Mesothelioma
Pericardial mesothelioma is the rarest form of this already rare cancer, and involves the membranes that surround the heart.  Mesotheliomas very rarely originate in the pericardium, but rather spread there from other areas.  Symptoms in the pericardial form of mesothelioma include chest pain and shortness of breath as is seen in the peritoneal and pleural forms; however, this patient may also experience heart palpitations.  This form of the disease is often seen as the direct extension of primary pleural or peritoneal mesotheliomas.  Since mesothelioma is most frequently pleural in origin, it is often associated with the lungs and chest area.

Benign vs. Malignant
Mesotheliomas can be benign or malignant.  The term “benign” is used to describe a tumor which is not cancerous and is likely to allow the patient’s recovery.  A benign mesothelioma may be less likely to manifest symptoms than other types, and in the pleural area, it can produce a slow growing tumor which may reach very large dimensions, possibly filling the entire pleural cavity. 
A malignant mesothelioma is one which is cancerous and growing uncontrollably.  Unfortunately, mesotheliomas are most often of the malignant variety.  This type of cancer will cause the associated pain and other symptoms specific to its location in the body.  All types of mesothelioma can cause a person to experience sudden, unexplainable weight loss.