Primary retroperitoneal mucinous cystadenoma with sarcoma-like mural nodule : a case report and review of the literature

Abstract

Primary retroperitoneal cystadenomas are extremely rare. This is the first report in literature to describe a primary retroperitoneal cystadenoma with a sarcoma-like mural nodule. A 45-year-old woman complained of a left-sided abdominal mass. A computed tomography scan revealed a cystic mass with a mural nodule, which seemed to originate from the tail of the pancreas. At laparotomy the cyst was not adhered to the pancreas but localized retroperitoneally. Histologic examination showed a mucinous cystadenoma with only foci of borderline malignancy with a mural "sarcoma-like" nodule. In view of the surgical and histopathological findings, the mucinous cystadenoma was regarded as primary retroperitoneal. This case demonstrates that in the era of radiological preoperative refinement, pathological diagnosis remains of utmost importance, especially for rare cases.

Fig. 1

Contrast enhanced CT scan shows images of a pancreatic cyst (arrowheads) originating from the tail of the pancreas (a) and a mural nodule within the wall of the cystic mass (b)

Fig. 2

Cyst wall with typical tall columnar mucous-secreting epithelium and fibrous wall (a). Low cellular proliferation with some stratification of the cells and slight nuclear atypia (b). Heterogenous proliferation of pleomorphic cells, spindle cells, osteoclast-like giant cells, and some mononuclear cells with some pigment (c). Detail of sarcoma-like nodule (d)