Case Report Simultaneous Renal Cell Carcinoma and Giant Retroperitoneal Liposarcoma Involving Small Intestine Aleksandr A. Reznichenko Division of Transplant Surgery, Department of Surgery, University of Cincinnati, 231 Albert Sabin Way, Suite 1555, Cincinnati, OH 45267-0519, USA Correspondence should be addressed to Aleksandr A. Reznichenko; areznik9@yahoo.com Received 23 May 2016; Accepted 25 July 2016 Academic Editor: Robert Stein Copyright © 2016 Aleksandr A. Reznichenko. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background. Te concomitant occurrence of a renal cell carcinoma and retroperitoneal sarcoma is extremely rare with only few cases being reported. Methods. We present a case of simultaneous renal cell carcinoma and exceptionally large size retroperitoneal sarcoma involving small intestine. Surgical resection of retroperitoneal sarcoma and simultaneous right nephrectomy were performed. Results. Patient developed recurrent and metastatic disease and underwent debulking surgery following by chemotherapy. Despite aggressive behavior of the retroperitoneal sarcomas, patient is currently (7 years afer simultaneous resection and nephrectomy) recurrence-free. Conclusions. Complete surgical resection is the mainstay of therapy for both renal cell carcinoma and retroperitoneal sarcoma. We present a case of simultaneous renal cell carcinoma and exceptionally large size retroperitoneal sarcoma. Debulking surgery and chemotherapy were helpful in our case. 1. Case Presentation A 61-year-old woman with history of morbid obesity, open cholecystectomy, and sarcoma excision from right lower extremity and from lef buttock (6 and 3 years ago, resp.) developed fatigue, abdominal pain, and large palpable mass occupying entire abdomen and right fank. A computer tomography (CT) scan showed 27 × 20 cm multilobular abdominal mass and 2.5 × 2.5 cm solid mass in the middle pole of the right kidney (Figures 1 and 2). Laboratory data was unremarkable, and serum creatinine was 0.7 mg/dL. Patient underwent exploratory laparotomy, resection of large retroperitoneal tumor (weight 5621 gm) en block with small intestine (Figure 3), and primary small bowel to small bowel anastomosis. Te mass in right kidney was resected and sent for frozen section, which revealed a malignant neoplasm of uncertain etiology. Right nephrectomy was performed. Final pathology showed renal cell carcinoma and myxoid liposarcoma involving small bowel and mesentery, with clear resection margins. Patient had uneventful recovery. Eight months later, the patient developed intraperitoneal recurrence of sarcoma and underwent debulking surgery. Subsequently, she developed recurrent and metastatic disease involving spleen, mesentery, liver, pelvis, and lungs and received multiple courses of chemotherapy, including Gemcitabine, Taxotere, and a clinical trial of Yondelis. Fol- lowing the chemotherapy treatment described above, the patient had near complete resolution of all intra-abdominal and pulmonary nodules and currently (7 years afer resection of retroperitoneal mass and nephrectomy) is recurrence- free. Liposarcoma is one of the most common sof tissue sarco- mas found in adults. It has a predilection for retroperitoneal space. Renal cell carcinoma is the most common tumor of the kidney [1]. Patients with primary malignant fbrous histiocytoma demonstrate a risk for developing a renal cell carcinoma [2]. Te concomitant occurrence of a renal cell carcinoma and retroperitoneal sarcoma is extremely rare with only few cases being reported [3, 4]. Surgical resection is the mainstay of therapy for both renal cell carcinoma and retroperitoneal sarcoma [1, 3, 4]. Tis case is noticeable because of the good outcome in our patient despite extremely aggressive behavior of the tumor Hindawi Publishing Corporation Case Reports in Surgery Volume 2016, Article ID 6021909, 2 pages http://dx.doi.org/10.1155/2016/6021909