IgG4-associated XXXX : clinicopathologic and immunohistochemical study of 3 cases.

@entity1 @entity66 @entity706 @entity3527 @entity5 @entity6437 @entity469 @entity812 @entity262 @entity189 @entity1698
@entity6437 are lesions characterized by proliferation of fibroblasts/myofibroblasts with variable chronic inflammatory cell infiltration. Recent studies have suggested that @entity6437 with abundant IgG4-positive plasma cells may be a unique entity associated with systemic @entity66 and should be distinguished from other similar lesions such as @entity5 and fibrohistiocytic-type @entity6437 . Localized @entity6437 has been rarely reported in the ureter, and IgG4-associated @entity1698 has not been described. We describe herein 3 cases of ureteral @entity6437 of IgG4-associated lymphoplasmacytic type, focusing on density of IgG4-positive plasma cells; infiltration pattern of eosinophils and histiocytes; presence of obliterative @entity3527 ; and immunohistochemical profiles of smooth muscle actin, @entity706 kinase, and @entity469 . Three @entity1 , 45- and 47-year-old @entity1 and 84-year-old @entity1 , all presented with @entity812 and ureteral narrowing by a mass effect. Microscopic examination of the resected ureters showed suburothelial masslike lesions with fibroblasts/myofibroblasts without atypia, abundant plasma cells, and scattered eosinophils and histiocytes. The lesion of the 47-year-old @entity1 showed obliterative @entity3527 in addition to the above findings. The lesion of the 84-year-old @entity1 was accompanied by @entity189 in situ in the overlying urothelium. Spindle cells were diffusely or focally positive for smooth muscle actin but negative for @entity706 kinase in all 3 cases. For each case, respectively, an average of 154, 112, and 50 plasma cells per high-power fields were immunoreactive for IgG4, a diagnostic feature of IgG4 @entity6437 . We described 3 cases of IgG4-associated @entity1698 with pathologic and immunohistochemical features that are compatible for lymphoplasmacytic type of @entity6437 . Further study is needed to characterize any relationship between this entity and @entity262 and/or urothelial carcinogenesis.
