Epithelial splenic cysts.

BACKGROUND Epithelial splenic cysts (ESC) are uncommon lesions of the spleen. The etiopathogenesis of these cysts is controversial, even if Burrig's theory is the most accredited. The histological distinction between epidermoid and mesothelial cysts may be difficult, particularly for monostratified epithelium. PATIENTS AND METHODS In the period between January 1986 and February 2004, 11 patients with ESC were studied. The history, physical findings, all relevant diagnostic studies and treatment were reviewed. All histological material was reviewed in detail with immunohistochemistry for CEA, CA 19-9, cytokeratin and calretinin. RESULTS Epidermoid cysts were positive for CEA, CA 19-9, and cytokeratin, but negative for calretinin. Mesothelial cysts were positive for cytokeratin and calretinin, but negative for CEA and CA 19-9. CONCLUSION Immunohistochemistry allows differential diagnosis between epidermoid and mesothelial cysts. With regard to etiopathogenesis, these data could mean that epidermoid and mesothelial cysts have distinct origins, though at variance with Burrig's theory. Although the ESC in this series were treated by open splenectomy, the recent approach by conservative and laparoscopic techniques offers great promise.