Benign peritoneal mesothelioma, also known as cystic or multicystic mesothelioma, is a non-cancerous form of cancer that develops in the peritoneum; the protective layer of cells surrounding the organs within the abdomen and the lining the abdominal walls. It is a rare form of mesothelioma that is not known to be associated with asbestos exposure. Most cases (about 85% of them) occur in women and most often develop in individuals with another condition affecting the pelvic region. Cysts primarily develop in the pelvic region of the abdomen along the peritoneum surrounding the rectum, bladder, and uterus or cul-de-sac and are contained within a mesothelium of their own.
Benign peritoneal mesothelioma shares few similarities with malignant peritoneal mesothelioma (malignant cancer of the peritoneum), though both occur in or on the mesothelium and both recur after resection (surgical removal of tumors). Other conditions that may somehow trigger benign peritoneal mesothelioma include endometriosis and pelvic inflammatory disease. There are a few documented cases in which benign peritoneal mesothelioma developed following a surgical procedure in the pelvic region. In general, however, the cause and effects of the condition are still a mystery to the medical community.
Benign peritoneal mesothelioma is very rare and not as severe as malignant mesothelioma, though it is a significant and serious medical condition that must be addressed. It is not life-threatening and is typically removed through surgery. In special circumstances, chemoperfusion many be employed to help surgeons eliminate cystic cells from the abdominal cavity. It cannot metastasize, but benign peritoneal mesothelioma tumors can grow to be very large. It is at larger sizes that the individual may begin to exhibit symptoms.
Benign Peritoneal Mesothelioma Types
There are two type of benign peritoneal mesothelioma; cystic and multicystic.
There are several similarities between the two types:
- Both occur in the abdomen
- Both are contained within a mesothelial lining that surrounds the cysts or the mass
- Both are visible in image tests
- Both require the same type of diagnostic procedures and treatments
- Both are composed of fluid filled cysts
The differentiating factors between the two types involve the way that the cysts are grouped together in the abdomen.
Cystic benign peritoneal mesothelioma is usually revealed as a mass (a tumor) comprised of many small, fluid filled cysts. The cysts are lined with a mesothelial layer of cells, just like the surrounding abdominal structures. Unlike other mesothelial conditions in the abdomen, cystic benign peritoneal mesothelioma masses do not contain muscle fibers; a discovery that is useful in determining that the mass is indeed mesothelioma and not a similar condition known as lymphangioma.
Multicystic benign peritoneal mesothelioma is also revealed as a mass comprised of many small, fluid filled cysts. The cysts are also surrounded by a layer of mesothelial cells. However, multicystic mesothelioma is characterized by many small cavities that each contains a small mass of cells. Multiseptate (having many cavities) and multilocular (having many chambers) cysts are created as the tumor grows, so that each cysts is separate from another.
Though neither type is life-threatening wit treatment, medical experts consider benign peritoneal mesothelioma to be an “intermediate” condition. Intermediate conditions pose no immediate threat of death, but are still significant conditions that are detrimental to the health of the individual. They pose the threat of complication if left unmonitored and untreated. However, documented cases of death due to benign peritoneal mesothelioma seem to only occur in individuals that refuse surgery to treat the condition.
Benign Peritoneal Mesothelioma Symptoms
Benign peritoneal mesothelioma is often asymptomatic (showing no symptoms) in the earliest stages of its development. As the cysts divide and replicate, the mass grows larger. Large tumors will cause an individual to exhibit symptoms. Some of the most common symptoms of benign peritoneal mesothelioma are:
- Abdominal Pain
- Abdominal Tenderness
- Palpable Abdominal Mass
- Abdominal Swelling (Distention)
These are very common symptoms and can signal the presence of myriad conditions. Therefore, it is important that other conditions such as these be eliminated in order to conclude a proper diagnosis. A proper diagnosis typically entails images and biopsy tests to confirm the presence of benign peritoneal mesothelioma.
Benign Peritoneal Mesothelioma Diagnosis
Because symptoms are not present until the tumor mass grows to a certain size, diagnosis at an early stage is most often incidental. Benign peritoneal mesothelioma is often diagnosed during examinations for other conditions when it is discovered in the earliest stages. Diagnosis may also occur after the tumor has grown large enough to cause symptoms for which the individual seeks treatment.
Additionally, the symptoms of benign peritoneal mesothelioma are common to other conditions, as well. These may include:
- Lymphangioma
- Ovarian Crystadenoma
- Crystadenomacarcinoma
- Endometriosis
- Teratoma
- Psuedomyxoma Peritonei
- Leiomyosarcoma
- Epithelial Inclusion Cysts
- Necrotic Leiomyoma
Other possible causes of symptoms must be eliminated. The most efficient method of eliminating most other conditions is through simple image scans. Sonograms, computerized tomography scans (CT Scans), and magnetic resonance imaging scans (MRI Scans) make quick work of eliminating other conditions that are not comprised of these types of cysts. The fluid filled cyst composition of benign peritoneal mesothelioma is visible on an image of the abdominal cavity; medical experts can easily differentiate between cystic and multicystic conditions with the images, since multicystic conditions are defined by the multilocular, multiseptate cyst structure.
Determining the nature of the tumor, whether or not it is benign or malignant (cancerous), requires the employment of a biopsy test. Benign peritoneal mesothelioma is most often diagnosed using a laparoscopic biopsy procedure, during which a tiny camera outfitted with a cutting tool is inserted into the abdomen where the tumor is located. With this instrument, a surgeon may extract a sample of the tumor for examination under a microscope. The types of cells that make up the tumor provide conclusive information for the diagnosis of benign peritoneal mesothelioma.
Benign Peritoneal Mesothelioma Treatment
Treating benign peritoneal mesothelioma is typically accomplished through a surgical procedure to remove the entire mass. In some cases, tumors may grow into sensitive areas of the abdomen where complete excision would pose a significant risk to a healthy organ.
Debulking procedures may be employed to remove as much of the tumor as possible, even if removing the entire mass is not advisable. While debulking is not the preferred method of treatment for benign peritoneal mesothelioma it is still better for the individual than no treatment at all.
Once removed, however, there is approximately a 50% chance that the tumor will begin to redevelop in the same location over a period of time. Therefore, it is necessary to monitor the individual so that future tumors are controlled.
In some cases, medical experts may choose to perform another type of treatment immediately following surgery. Doctor’s may rinse the abdomen with medication intended to destroy remaining cysts in an effort to prolong the period of time before the tumor begins to redevelop. This procedure may also assist in preventing the recurrence of benign peritoneal mesothelioma in the future.
