Sclerosing angiomatoid nodular transformation of the spleen related to IgG 4 -associated disease: report of a case

Sclerosing angiomatoid nodular transformation (SANT) of the spleen is a rare benign vascular mass, with fewer than 100 cases documented. It is generally recognized as a vascular lesion that develops in the red pulp of the spleen; however, its pathogenesis is not clearly defined. We report a case of SANT of the spleen, which presents evidence to support the hypothesis that this disease entity is associated with IgG 4 -associated disease. Microscopically, the tumor was composed of multiple vascular structures separated by fibrous connective tissue and immunohistochemical examination revealed positive staining for CD31, CD34, factor VIII, and IgG 4 . Further research based on large number of cases is warranted to clarify the pathogenesis of this tumor.