Abstract

Introduction: Right retroperitoneal cyst was diagnosed in a 42 years old woman who had a previous right

nephrectomy 28 years ago. The cyst was excised by the same flank incision. Microscopic examination of cyst

wall showed that it is lined with a single cuboidal epithelium. The cells were characterized by ample eosinofilik

cytoplasm. We didn’t find any atypia or mitoses among them. Immunostaining showed that the cyst lining cells

were positive for calreitinin and pansitokeratin, PAS+alcian blue also positive in a focal area. These findings

suggest that the cyst has a mesothelial origin. In this paper we discuss the retroperitoneal cysts and their

treatments.