Uncommon retroperitoneal tumour: follicular dendritic cell sarcoma.

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

Patients And Methods: 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.

Results: 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.

Conclusions: 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.