Multicystic mesotheliomas are a rare benign subtype of mesothelioma.
The nomenclature for this condition can be confusing due to the use of multiple interchangeable different synonyms that put it together with the peritoneal inclusion cysts. Although there is still some debate on this matter, this article will refer to multicystic mesotheliomas as true neoplasms, distinguishing it from peritoneal inclusion cysts, a term reserved for those cysts secondary to intra-abdominal inflammation and with its fluid content originated from the ovarian stroma.
Different from malignant peritoneal mesothelioma, there is no association with asbestos exposure 5,8,9.
Patients generally present with non-specific symptoms such as abdominal or pelvic pain, or distension. A palpable abdominal or pelvic mass may eventually be felt on clinical examination.
Typically comprises multiple grape-like clusters of cysts which are lined with mesothelium and separated by fibrous tissue components.
Primarily occurs in the pelvic peritoneum, but can be multicompartmental 2.
May appear as a multicystic pelvic mass 2,3.
- typically seen as a well-defined low attenuating (cystic) pelvic mass
- calcification is generally not a feature
Can better delineate the pelvic cystic mass. Reported signal characteristics include:
- T1: fluid components show low signal
- T2: fluid components show high signal
- C+ (Gd): may show enhancement of septa
Treatment and prognosis
Surgery is the preferred option for localized lesions. The tumor tends to recur locally (25-50% of cases) 3,6. Not thought to be chemo- or radiosensitive 2. May respond to hormonal therapy 5.
The general differential includes:
- peritoneal inclusion cysts
- abdominopelvic cystic lymphangioma: tends to affect younger patients
- ovarian cystadenoma
- ovarian cystadenocarcinoma
- cystic teratoma
- pseudomyxoma peritonei
- cystic mucinous tumor of the pancreas
- 1. Koo PJ, Wills JS. Case 146: Benign multicystic mesothelioma. Radiology. 2009;251 (3): 944-6. doi:10.1148/radiol.2513071235 - Pubmed citation
- 2. Bui-mansfield LT, Kim-ahn G, O'bryant LK. Multicystic mesothelioma of the peritoneum. AJR Am J Roentgenol. 2002;178 (2): 402. AJR Am J Roentgenol (full text) - Pubmed citation
- 3. O'Neil JD, Ros PR, Storm BL et-al. Cystic mesothelioma of the peritoneum. Radiology. 1989;170 (2): 333-7. Radiology (abstract) - Pubmed citation
- 4. Wong WL, Johns TA, Herlihy WG et-al. Best cases from the AFIP: multicystic mesothelioma. Radiographics. 24 (1): 247-50. doi:10.1148/rg.241035068 - Pubmed citation
- 5. Park JY, Kim KW, Kwon HJ et-al. Peritoneal mesotheliomas: clinicopathologic features, CT findings, and differential diagnosis. AJR Am J Roentgenol. 2008;191 (3): 814-25. doi:10.2214/AJR.07.3628 - Pubmed citation
- 6. Pickhardt PJ, Bhalla S. Primary neoplasms of peritoneal and sub-peritoneal origin: CT findings. Radiographics. 25 (4): 983-95. doi:10.1148/rg.254045140 - Pubmed citation
- 7. Elsayes KM, Staveteig PT, Narra VR et-al. MRI of the peritoneum: spectrum of abnormalities. AJR Am J Roentgenol. 2006;186 (5): 1368-79. doi:10.2214/AJR.04.1522 - Pubmed citation
- 8. Ruri Lee, Angela Tong, Boaz Kurtis, Anthony G. Gilet. Benign Multicystic Peritoneal Mesothelioma: AIRP Best Cases in Radiologic-Pathologic Correlation. (2016) RadioGraphics. 36 (2): 407-11. doi:10.1148/rg.2016150157 - Pubmed
- 9. Park JY, Kim KW, Kwon HJ et-al. Peritoneal mesotheliomas: clinicopathologic features, CT findings, and differential diagnosis. AJR Am J Roentgenol. 2008;191 (3): 814-25. doi:10.2214/AJR.07.3628 - Pubmed citation