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

Abstract

Introduction and importance: 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.

Case presentation: 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.

Clinical discussion: 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.

Conclusion: 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.

Keywords: Case report; Liposarcoma; Nephrectomy; Retroperitoneum; Surgery.

Fig. 1

CECT showing huge retroperitoneal liposarcoma (white arrow) with high-fat attenuation and septation. The tumor is encasing the right kidney (blue arrow) and displaces the viscera (yellow arrow). (A-axial, B-sagittal, C-coronal view). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

Fig. 2

Intra-operative view showing tumor in -situ (white arrow).

Fig. 3

Gross picture showing huge tumor including kidney (yellow arrow). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

Fig. 4

Hematoxylin and eosin stain (magnification ×100) showing atypical adipocytes with eccentric nuclei.

Fig. 5

CECT of abdomen and pelvis showing heterogeneously enhancing soft tissue lesion (white arrow) in the right side of abdominopelvic cavity abutting and displacing adjacent bowel loops and urinary bladder.