Uncommon retroperitoneal tumour: follicular dendritic cell sarcoma

Retroperitoneal Follicular Dendritic Cell Sarcomas represents rare tumours with aggressive biologic behaviour. Accurate diagnosis requires a combination of both morphological and immunohistochemical analyses.

A 61-year-old man was referred to our Department with a left perinephric mass. Computed tomography scan showed a 5.5 cm circumscribed mass in front of the left renal vein abutting the first jejunal loop, with moderate heterogeneous contrast enhancement. Positron emission/computed tomography showed increased focal uptake in the lesion.

A retroperitoneal tumor located behind the first jejunal loop was found at laparotomy, encompassing the superior mesenteric vessels. Excision with en-bloc segmental small bowel resection was performed. Morphological and immunohistochemical analyses were consistent with Follicular Dendritic Cell Sarcoma.

Complete surgical resection in specialized multidisciplinary centers represents the treatment of choice for both primary or recurrent lesions since there is still no consensus on the role of adjuvant radio-chemotherapy.