Huge retroperitoneal liposarcoma encasing right kidney: A case report from Nepal

Retroperitoneal liposarcoma is a rare entity originating from adipocytes. Before showing any symptoms, it can grow hugely and envelop nearby structures. Surgery is the optimum course of treatment, however, well-differentiated liposarcomas make it challenging to discern between malignant and normal adipocytes during surgery.

We report a case of a 62-year-old male referred to evaluate his abdominal distention presented for four years. Recently he had developed loin pain for six months. A computerized tomography scan showed extensive tumor encompassing the right kidney and ureter, colon, and duodenum, however, exploratory laparotomy revealed free colon and duodenum. Complete resection of the mass with a right nephrectomy was performed. Subsequently, a histopathological assessment of the resected specimen confirmed the diagnosis of well-differentiated liposarcoma. Adjuvant chemotherapy was initiated as the tumor was a high-risk sarcoma but local recurrence was observed after 2 years despite surgery and chemotherapy.

Imaging modalities are the mainstay of preoperative diagnosis. Preferably, surgical resection with a tumor-free margin is recommended to avoid tumor recurrence which remains the primary challenge. This, along with the grade of the tumor, multifocal disease, and invasion of adjacent structure dictate the prognosis of the disease. Adjuvant chemotherapy and radiotherapy are not regarded as standard therapies for resectable retroperitoneal liposarcoma, although further research is still needed to determine their value in the case of high-risk sarcoma.

Retroperitoneal liposarcoma has the potential to present as huge asymptomatic masses which with an added predilection for recurrence poses a huge challenge to any surgeon.