14. Sclerosing angiomatoid nodular transformation (SANT) of the spleen: A perth experience

Background Sclerosing angiomatoid nodular transformation of the spleen (SANT) is an uncommon, usually incidental, nonneoplastic vascular splenic lesion first described in 2004 1 . Recent articles have suggested association of SANT with IgG4-related sclerosing disease and with Epstein-Barr virus RNA expression 2 . Aim A retrospective review of SANT cases reported in three Perth metropolitan hospitals over the past 20 years. Methods A computer-assisted search of all reported SANT cases from the Perth metropolitan hospital Anatomical Pathology database for the period 1992-2012 was performed. Slides were reviewed from the identified cases and, where formalin-fixed paraffin-embedded (FFPE) tissue was available, further immuno-histochemical stains were performed including CD8, CD30, CD31, CD34, D2-40, ERG, CD138, IgG, IgG4 and EBV-encoded small RNA (EBER). Results Four cases were identified, including three splenectomy specimens and one post-mortem specimen. All had the characteristic CD31/CD34/CD8 vascular immunophenotype 1 . Endothelial expression of CD30 was found in two of the cases. Architectural derangement was highlighted by an altered pattern of ERG immu-noperoxidase nuclear expression in the sinusoidal epithelium of SANT angiomatoid nodules. EBER was negative in the three cases with available FFPE material and no convincing evidence for IgG4-related sclerosing disease was identified. Conclusion Four cases of SANT are described, including immunohistochemical adjuncts to their diagnosis. No evidence for an association with EBV infection or IgG4-related sclerosing disease is identified in these cases.