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Retroperitoneal Sarcoma Surgery

The retroperitoneum refers to the “back of the abdomen.” Sarcomas in the retroperitoneum are very rare cancers for which treatment can be extremely challenging. The Retroperitoneal Sarcoma Surgery Program at the University of Southern California (USC), Keck School of Medicine offers extensive experience and the latest, integrated multidisciplinary approaches in the treatment of this disease.

Retroperitoneal sarcomaAlthough retroperitoneal sarcomas represent only 0.2% of all adult cancers, the vast majority of tumor types are either 1) liposarcoma (well differentiated / dedifferentiated) or 2) leiomyosarcoma. Other tumor types such as solitary fibrous tumor, malignant peripheral nerve sheath tumor, and undifferentiated pleomorphic sarcoma can also be seen in this body location. Tumor removal by surgery is the main treatment for all retroperitoneal sarcomas; however these tumors are usually massive in size and touch upon or invade into adjacent organs and vital structures (e.g. major blood vessels) making surgery very difficult. Effective surgical treatment of retroperitoneal sarcoma combines surgical skill and technique with an intimate knowledge of this disease and specifically, the unique tumor characteristics in each patient's situation (e.g. liposarcoma vs. leiomyosarcoma, primary vs. recurrent disease). This approach offers the patient the best chance of a good outcome from a cancer standpoint without the morbidity of unnecessarily aggressive surgery. If feasible in terms of cancer control, organs (e.g. kidney) are preserved. To help optimize outcome, sometimes chemotherapy or radiation therapy is used before or after surgery.

William Tseng, MDThe USC Retroperitoneal Sarcoma Surgery Program is led by Dr. William Tseng, a cancer surgeon whose clinical practice focuses on soft tissue sarcoma. He brings experience in this disease, particularly liposarcoma, from the University of Texas, MD Anderson Cancer Center. Dr. Tseng combines not only clinical and surgical expertise in retroperitoneal sarcoma but he is actively engaged in research to try to find alternative treatments (e.g. immunotherapy) that might someday be combined with or even replace surgery. Dr. Tseng has numerous publications about current treatment and ongoing research in retroperitoneal sarcoma. In addition, Dr. Tseng is an active member of the Trans-Atlantic Retroperitoneal Sarcoma Working Group. Through this international collaboration, Dr. Tseng is at the forefront of the field and has even helped to formulate standardized treatment guidelines for this disease.

A distinct advantage of the USC Retroperitoneal Sarcoma Surgery Program is the integrated, multidisciplinary approach to treatment that is personalized to each individual patient situation. Each patient's case is discussed at our multidisciplinary Tumor Board, with expertise input from sarcoma pathologists, radiologists, medical oncologists and radiation oncologists. If needed depending on the patient's case, in the operating room, Dr. Tseng--himself, a cancer surgeon--works together with surgical experts as part of a "second" multidisciplinary team.

The USC Retroperitoneal Sarcoma Surgery Program Team:

  • Alexander Fedenko, MD – soft tissue pathology
  • Dakshesh Patel, MD – musculoskeletal radiology
  • James Hu, MD – medical oncology
  • Omar Ragab, MD – radiation oncology, brachytherapy

Select Publications – Retroperitoneal Sarcoma

  • Tseng WW, Eichler CM, Warren RS, Nakakura EK. Complete and Safe Resection of Challenging Retroperitoneal Tumors: Anticipation of Multi-organ and Major Vascular Resection and Use of Adjunct Procedures. World J Surg Oncol 2011 Nov 4; 4(9):143. PMID: 22054416
  • Tseng WW, Demicco EG, Lazar AJ, Lev DC, Pollock RE. Lymphocyte Composition and Distribution in Inflammatory, Well-Differentiated Retroperitoneal Liposarcoma: Clues to a Potential Adaptive Immune Response and Therapeutic Implications. Am J Surg Pathol 2012 Jun; 36(6):941-4. PMID: 22446945
  • Tseng WW, Madewell JE, Wei W, Somaiah N, Lazar AJ, Ghadimi MP, Hoffman AL, Pisters PW, Lev DC, Pollock RE. Locoregional Disease Patterns in Well Differentiated and Dedifferentiated Retroperitoneal Liposarcoma: Implications for the Extent of Resection? Ann Surg Oncol 2014 Jul; 21(7): 2136-43. PMID: 24705628
  • Ikoma N, Torres KE, Somaiah N, Hunt KK, Cormier JN, Tseng W, Lev D, Pollock R, Wang WL, Feig B. Accuracy of Preoperative Percutaneous Biopsy for the Diagnosis of Retroperitoneal Liposarcoma Subtypes. Ann Surg Oncol 2015 Apr;22(4):1068-72. PMID:25354575
  • Tseng WW, Malu S, Zhang M, Chen J, Sim GC, Wei W, Ingram D, Somaiah N, Lev DC, Pollock RE, Lizee G, Radvanyi L, Hwu P. Analysis of the intratumoral adaptive immune response in well differentiated and dedifferentiated retroperitoneal liposarcoma. Sarcoma 2015: 547460. PMID:25705114
  • Olimpiadi Y, Song S, Hu JS, Matcuk GR, Chopra S, Eisenberg BL, Sener SF, Tseng WW. Contemporary Management of Retroperitoneal Soft Tissue Sarcomas. Curr Oncol Rep 2015 Aug;17(8): 39. PMID: 26092408
  • Khoury M, Sim GC, Harao M, Radvanyi L, Amini B, Benjamin RS, Pisters PWT, Pollock RE, Tseng WW. Multicystic Dedifferentiated Retroperitoneal Liposarcoma: Tumor Cyst Fluid Analysis and Implications for Management. BMJ Case Rep 2015 Jul 8;2015. PMID: 26156843
  • Tseng WW, Pollock RE, Gronchi A. The Trans-Atlantic Retroperitoneal Sarcoma Working Group (TARPSWG): “Red wine or white”? Ann Surg Oncol. 2016 Dec;23(13):4418-4420. PMID: 27613555
  • Tseng WW, Gronchi A. Surgery for recurrence in retroperitoneal leiomyosarcoma: Is it all about selection? J Surg Oncol. 2017 Sep;116(3):267-268. PMID: 28672078
  • Livingston JA, Bugano D, Barbo A, Lin H, Madewell JE, Wang WL, Lazar AJ, Tseng WW, Roland CL, Feig BW, Pollock R, Conley AP, Benjamin RS, Patel S, Somaiah N. Role of chemotherapy in dedifferentiated liposarcoma of the retroperitoneum: defining the benefit and challenges of the standard Sci Rep 2017 Sep 19;7(1):11836. PMID: 28928422
  • Tseng WW, Seo HJ, Pollock RE, Gronchi A. Historical Perspectives and Future Directions in the Surgical Management of Retroperitoneal Sarcoma J Surg Oncol (in press)
  • Tseng WW, Pollock RE, Gronchi A. Retroperitoneal Sarcomas: Big tumors that Involve More than Just “Getting It Out”. J Surg Oncol (in press)

Articles - Retroperitoneal Sarcoma




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