“Mesothelioma” usually refers to malignant mesothelioma, which is a type of cancer caused by asbestos exposure. However, there is also a non-cancerous form of the disease, known as benign mesothelioma. It is a rare condition more common in men than women, but its causes are not fully understood. There are different types of benign mesothelioma and it can be an indicator for later development of malignant mesothelioma, which is why physicians continue to monitor patients.

Tumors form as healthy cells start rapidly dividing and forming a solid lump of cells, but in the benign form of the disease, these cell formations are not cancerous. Cancer is only related to malignant tumors, but not benign ones. One of the main differences between the two forms of the disease is mortality. There is currently no cure for malignant mesothelioma and it has a high mortality rate, while benign mesothelioma can be treated and usually has good prognosis.

Benign Mesothelioma Features

There are numerous types of benign mesothelioma, divided according to the characteristics of the cells, and all of them are rarer than malignant mesothelioma. Benign Multicystic Peritoneal Mesothelioma (BMPM) develops in the peritoneal cavity, particularly among young and middle-aged women, and it causes abdominal pain and swelling, while Well-Differentiated Papillary Mesothelioma (WDPM) has a greater probability of becoming malignant. The majority of the cases of WDPM occur in the peritoneum (abdominal cavity) of women 30 to 40 years of age, but it can also develop in the pericardium (heart sac), pleura, and tunica vaginalis (testicular lining), and the most common symptoms are pain and fluid buildup (effusions).

In addition, the benign mesothelioma that affects the tunica vaginalis and the uterine wall is known as an Adenomatoid Tumor (AT), while Localized Fibrous Tumor (LFT) occurs in the surface of mesothelial cells in the pleura. LFT can also develop in the pericardium, tunica vaginalis, and peritoneum. Approximately half of the patients do not experience any symptoms, but when it occurs, it can include cough, pain, and breathlessness. The diagnosis of the disease is usually conducted through physical examination and with exams like a chest x-ray, CT scan of the chest, or open lung biopsy.

Differences Between Malignant and Benign Mesothelioma

Despite both being designated as mesothelioma, there are major differences between malignant and benign mesothelioma. Benign mesothelioma is not only associated with asbestos exposure and it does not take decades to first manifest, unlike malignant mesothelioma. Another difference is that benign mesothelioma does not spread to nearby tissue, making it less severe and dangerous. As malignant mesothelioma progresses, cancer tends to spread and reach other parts of the body. However, both cause discomfort and can have other serious complications.

Both benign and malignant mesothelioma can grow to a large size in the body and reoccur, but only malignant mesothelioma damages the healthy tissue and organs and metastasizes to other body parts through the blood and lymph nodes. The symptoms of the diseases are similar, including shortness of breath, chest pain, and chronic cough, but in the case of malignant mesothelioma, patients usually experience fever, night sweats, and weight loss. As the disease progresses, the symptoms tend to become more severe. The diagnosis is also similar.

Benign Mesothelioma Treatment

The treatment for benign mesothelioma is usually based on the surgical removal of the tumors, unlike malignant mesothelioma, which often needs additional treatment with chemotherapy or radiation therapy. Given the fact that the tumors are non-cancerous and do not spread, the surgery is often effective. 75% of patients have tumors in the lungs and undergo thoracotomy surgeries, which involves the removal of a segment of the lung, a lobe, or the entire organ. Other surgical procedures are also used depending on the size and location of the tumor.

The majority of patients experience full recovery after the surgery, and 90% of them never suffer tumor reoccurrence or cancer development. However, up to 10 years after treatment, it is still possible for the disease to return. In addition, complications may also develop after the surgery, despite the fact that benign mesothelioma is a relatively harmless disease. The most common complication is fluid buildup in the pleural spaces, which results in lung and heart pressure and can be treated with a fitted chest drain following the surgery to remove excess fluid and prevent effusion.