Benign Mesothelioma

Mesothelioma comes in benign and malignant forms. Benign mesothelioma is not considered life-threatening by itself; however, its presence is a risk factor for future development of the malignant form of mesothelioma.

The most important difference between benign and malignant mesotheliomas is that the benign tumors are not cancerous and do not spread to nearby tissues. They are sometimes referred to as “localized” or “solitary” mesothelioma because of their non-invasive nature. Because benign mesotheliomas are not cancerous and do not invade adjacent tissues, they are easier to control and treat than the malignant form.

Benign mesothelioma is very rare, and makes up less than 10% of all mesothelioma cases in the United States. Unlike malignant mesothelioma, which is known to be caused by asbestos exposure, the causes of benign mesothelioma are unknown, and there are no known methods for preventing the benign tumors.

Symptoms of Mesothelioma

Benign mesothelioma often has no apparent symptoms. It is frequently discovered during routine medical exams or x-rays for other health concerns. However, when symptoms are apparent, they are typically the same symptoms felt by someone with malignant mesothelioma. Both types of tumors create physical pressure on surrounding bodily organs that in-turn creates feelings of discomfort. Symptoms of benign mesothelioma of the chest cavity include shortness of breath, chest pain, chronic cough, weakness, weight loss, difficulty swallowing, raspy voice, fever, and coughing up blood. Clubbed fingers are sometimes a symptom of benign chest mesotheliomas, because they indicate a possible lack of oxygen in the blood due to pressure of the tumors on the lungs. Symptoms of benign mesothelioma of the abdominal cavity include abdominal pain or swelling, a visible mass or a mass that can be felt upon external examination, nausea and vomiting, loss of appetite, bowel obstruction, blood clotting abnormalities, fever, anemia, chest pain, and weight loss. Symptoms of benign mesothelioma around the heart include chest pain, difficulty breathing, fatigue, chronic cough, and heart palpitations.

Diagnosis of Benign Mesothelioma

Benign mesothelioma is diagnosed in the same way as malignant mesothelioma, because it is impossible to tell the two types of tumors apart without detailed testing. Diagnosis would begin with a thorough review of the patient’s medical history, asking especially about asbestos exposure to determine the likelihood that the tumor is malignant. A thorough physical examination would then be completed, most likely with x-rays of the chest or abdomen, depending on where the suspected tumor is located. A CT scan or an MRI may also be used so the patient’s health care provider can obtain a clearer visual image of the affected area than would be possible with an x-ray. The final stage in the process would be a biopsy, which is required to confirm diagnosis of mesothelioma, as well as determine whether the tumor is benign or malignant. During a biopsy, a sample of the tumor tissue is removed and examined under a microscope. There are a few different methods that may be used to remove tissue for a biopsy, and the method used depends on where the suspected tumor is located in the patient’s body. Tissue collection methods include inserting a needle into the affected area and cutting a small hole in the patient’s body and inserting a thin tube with a camera to get a closer look at the tumor. More invasive surgery may be required if a sufficient tissue sample cannot be obtained with non-invasive methods.

Treatment of Benign Mesothelioma

Benign mesothelioma requires treatment because the tumor may cause pressure damage on adjacent organs and because the tumor may become malignant if left alone. Complete surgical removal of the benign tumor is the recommended treatment, and this surgery is usually successful. For benign mesothelioma of the lungs, a possible complication of the surgery is what is known as “pleural effusion” or fluid leaking into the membranes around the lungs. Follow-up after surgery is necessary to make sure the tumor does not return, especially incase it returns as a malignant form. Recurrence can happen several years after initial discovery and removal of the tumor, so long term follow-up is often needed.