Clinicopathological features of low-grade malignant cystic mesothelioma of the peritoneum / 解放军医学杂志

ABSTRACT

Objective To study the clinicopathologic features and prognosis of low-grade malignant cystic mesothelioma of the peritoneum (LGMCMP). Methods 25 cases of LGMCMP were analyzed retrospectively on their clinicopathologic features and immunohistochemical and electron microscopic findings, therapeutic approach and prognosis were also studied. Results Of 25 cases, 18 were females and 7 were males with a mean age of 39.6 years (range 16-84 years). According to their imaging characteristics, symptoms and physical signs, three morphological patterns of these tumors were found, i.e. localized cystic mass, multiple cystic nodules and diffuse cystic nodules. Immunohistochemical staining showed that the neoplastic cells were positive for CK, Vimentin, EMA, and anti-mesothelial cell antigen. Histochemically, the tumors were positive for CI but negative for HCI. Electron microscopic study of 11 cases revealed that the neoplastic cells had profuse slender microvilli on cell surface, large amount of microfilaments (tono-filaments) and abundant desmosomes. Conclusion LGMCMP is an uncommon neoplasm of low-grade malignancy, generally occurring in young women with distinct clinicopathologic features.