Multicystic mesothelioma is an intermediate, benign (non-cancerous), and rare form of mesothelioma that develops in the pelvis of females. Most cases (85%) occur in or on a part of the pelvic peritoneum in young and middle-aged women. The pelvic peritoneum includes the uterus, bladder, rectum, or cul-de-sac.
Multicystic mesothelioma is classified as a form of mesothelioma because it originates in or on the mesothelium. There are few similarities with other forms of mesothelioma regarding cause and effect. According to reports published by the National Institute for Biotechnology Information, it has not been definitively linked to asbestos exposure and its cause is unclear. It is speculated that it may develop because of another condition such as endometriosis. It may also develop following a surgical procedure in the pelvic region.
Unlike malignant peritoneal mesothelioma (malignant abdominal mesothelioma), multicystic mesothelioma is not life-threatening and is not able to metastasize, though it is slightly more invasive than a benign adenomatoid. It requires no chemotherapy or radiation, though short term chemotherapy drugs may be introduced in some cases, and is only removed if convenient or necessary to the patient’s overall health and well being.
Multicystic Mesothelioma Symptoms
It is the size of the mass that determines the type of symptoms associated with multicystic mesothelioma and ultimately determines the necessity for treatment. As cysts divide over time, the mass of cysts will grow larger. When the mass comes to interfere with other organs or applies pressure to nerves, for example, the following symptoms may be presented in a patient with multicystic mesothelioma.
- Abdominal Pain
- Abdominal Tenderness
- Abdominal Mass
Multicystic mesothelioma may be asymptomatic for a very long time, revealing no symptoms at all. In fact, the multicystic mesothelioma cysts are often found (18% of cases, according to one study) while looking for other conditions and through image scans of the abdomen.
Multicystic Mesothelioma Diagnosis
It is often impossible to discern the difference between multicystic mesothelioma and other conditions without an operative procedure to obtain a sample of the cyst of biopsy. Some of the other possible conditions include:
- Lymphangioma
- Ovarian Crystadenoma
- Crystadenomacarcinoma
- Endometriosis
- Teratoma
- Psuedomyxoma Peritonei
- Leiomyosarcoma
- Epithelial Inclusion Cysts
- Necrotic Leiomyoma
Images of the abdomen prior to biopsy reveal multiseptate (multiple cavities), multilocular (divided into many small chambers) cysts. In other words, each new division of a cyst grows into a small cavity that separates it from the other cyst. Medical experts may employ a variety of imaging tests to gain a complete illustration of the multicystic mesothelioma’s composition, as described in the table below.
| Multicystic Mesothelioma Diagnostic Image Testing |
|---|
| Sonogram | A sonogram shows multicystic mesothelioma as a multiseptate cystic mass, having many dividing “walls”. |
| Computerized Tomography (CT) Scan | A computerized tomography scan shows multicystic mesothelioma with a clearly visible multilocular mass, with each cysts being self-contained in its own chamber. |
| Magnetic Resonance Imaging (MRI) Scan | A magnetic resonance imaging scan shows multicystic mesothelioma with clearly visible lesions that are hypointense on the image. (The lesions appear stark in comparison to nearby tissue.) |
Since multicystic mesothelioma shares common characteristics with other conditions in the peritoneum, a biopsy is required to make a proper diagnosis. In other types of mesothelioma, this is usually accomplished (at least initially) through a needle biopsy in which a small sample is draw out through a long surgical needle. This isn’t as appropriate for multicystic mesothelioma, a sample of which is taken most commonly through laparoscopy. (This involves a small incision in the skin through which tiny, laparoscopic instrument such as a camera and special tool for removing a sample may be inserted.) Laparoscopy may also be utilized to remove cysts later, if treatment is necessary.
Multicystic Mesothelioma Treatment
Treatment for multicystic mesothelioma is often conducted based on necessities, since the cysts are not life threatening. Because they can cause pain and other complications when the cysts amass, a number of treatment options may be employed to either reduce the size of the mass or remove the mass entirely. Surgery is the primary method through which debulking or removal of the mass is accomplished.
If multicystic mesothelioma is limited to a local area of the abdomen and has not grown into delicate areas where resection (removal) becomes risky, a total excision of the mass is preferred. In cases where the mass is very large, a debulking operation may be more appropriate. Through debulking, a procedure also known as “cytoreduction”, surgeons remove a large portion of the mass, but not all of it.
The complications or side effects of tumor resection or excision are those carried by any form of open surgery and are general to all abdominal surgeries, including:
- Anesthetic Allergies
- Infection
- Bleeding
- Sore throat
- Difficulty in urination or constipation
- Hypertension
- Pain and discomfort
Multicystic mesothelioma can redevelop after complete excision and may grow large again following a debulking surgery. Therefore, some medical experts prefer to perform a follow-up procedure involving a non-systemic chemotherapy treatment that is still considered an experimental therapy. Traditional chemotherapy treatments for malignant mesothelioma are introduced into the veins of the patient, where the chemotherapy drugs flow through the body and into the cancer cells. This causes widespread damage to healthy cells and results in the many common side effects of chemotherapy.
Non-systemic chemotherapy treatments for multicystic mesothelioma are not introduced into the blood stream. Often immediately following resection, while the abdominal cavity is still open, doctors wash the interior of the abdominal cavity with a heated chemotherapy drug solution. The solution is much more concentrated than systemic chemotherapy solutions and is only allowed to remain in the cavity for a short period of time. It is not pooled in the cavity, rather used as a rinsing agent to kill any remaining cystic cells in the abdominal cavity to prevent or prolong the redevelopment of cysts. This treatment may simply be referred to as “chemoperfusion”. Officially, this experimental multicystic mesothelioma treatment is called intraperitoneal hyperthermic chemoperfusion and may also be referred to as hyperthermic intraperitoneal chemotherapy or intraoperative chemohyperthermic peritoneal perfusion.
