Benign mesothelioma is a tumor that starts in the mesothelium, the lining of the chest and abdominal cavities. Unlike malignant mesothelioma, benign tumors do not cause cancer — they generally do not spread to other parts of the body or invade the tissues.1
Benign fibrous tumor of the pleura
When the benign mesothelioma occurs in the chest cavity along the lining of the lungs it is called a solitary fibrous tumor of the pleura.2 This type of growth occurs more often in men than women, and about half of the people who have a fibrous tumor do not experience symptoms. When there are symptoms it is because the tumor is large and presses on the lungs, causing a cough, trouble breathing or chest pain. The tumor is usually removed by surgery but can come back.
Peritoneal cystic mesothelioma is a rare tumor that grows in the lining of the abdomen, called the peritoneum. It manifests as a painful mass in the area of the stomach or pelvis, or along the lining of the organs.3 It occurs more often in women than men, and more often in the pelvic region.4 Some researchers have suggested that early removal of the tumor is important for preventing complications and aggressive growth even though cystic mesothelioma is considered benign.5
Benign multicystic mesothelioma is considered to be a gynecological tumor, though a few cases have been reported in men and outside the abdominal area. The condition may be called by other names depending on its appearance to the doctor. Multicystic mesothelioma is associated with other women’s health disorders but is a very rare tumor.6
Well differentiated papillary mesothelioma (WDPM)7,8 is a rare epithelial tumor of the pelvic region or uterus in women, though it sometimes starts in the chest cavity and has been reported in men. Papillary mesothelioma generally does not cause symptoms, but when found the tumors are surgically removed.
Benign versus malignant mesothelioma
There are key differences between benign and malignant mesothelioma:
- Malignant mesothelioma is caused by asbestos exposure, but benign mesothelioma tumors, especially papillary mesothelioma, have not been clearly linked to this cause.8
- Benign mesothelioma generally does not cause cancer, but malignant mesothelioma spreads to other parts of the body if left untreated.1
- Benign mesothelioma tumors require minimal treatment and are generally removed by surgery,1 but malignant mesothelioma may require chemotherapy and radiation or new therapies being developed in clinical trials.9