Author(s): Jude Immanuel P. Mascariñas, MD; Vanessa Maris C. Cariño, MD; Francisco F. Firmalo III, MD, FPCS, FPUA and Glenn P. Villanueva, MD, FPCS, FPSGS

Introduction:
Liposarcoma is a malignant mesenchymal neoplasm composed of adipose tissue with varying degrees of atypia. While generally indolent, some tumors have the potential to grow enormously particularly if located in the retroperitoneum. We report a 49-year-old female generally asymptomatic except for a 1-year history of gradual abdominal enlargement. Contrast-Enhanced Computed Tomography (CT) of the abdomen showed a large retroperitoneal mass with characteristic features consistent with liposarcoma. On laparotomy, the mass was encapsulated with good plane of dissection, great vessels were preserved, however the right kidney and suprarenal gland were undetachable from the primary tumor hence was removed en bloc with the liposarcoma. The post-operative course was uneventful with excellent outcome after 6 months of follow-up. Final histopathologic diagnosis revealed low-grade, dedifferentiated liposarcoma, which has favorable prognosis following radical surgery.

Conclusion:
Retroperitoneal liposarcomas are rare, locally aggressive tumors with an indolent course. They cause mass-effect symptoms when they reach extreme dimensions. Complete surgical resection with negative margins is the mainstay of treatment and provides the best chance of attaining disease-free survival.

Key words: Liposarcoma, sarcoma, renal veins, laparotomy, nephrectomy

DOI: