罕見案例報告 – 後腹腔去分化性脂肪肉瘤與未被侵犯之腎臟
鍾尚融、薛又仁、蕭毅君、賴昱維、黃建榮、陳建成1、周榮茂2
台北市立聯合醫院仁愛院區 泌尿科，1消化外科，2病理科
Retroperitoneal dedifferentiated liposarcoma with a compressed invasion-free kidney - a rare case report
Shang-Rong Zhong, Thomas Y. Hsueh, Yi-Jiun Hsiao, Yu-Wei Lai, Andy C. Huang, Chien-Cheng Chen, Jung-Mao Chou
Divisions of Urology, Gastrointestinal Surgery1 and Pathology2, Ren-Ai Branch, Taipei City Hospital, Taipei, Taiwan
Introduction: Retroperitoneal soft tissue sarcoma (RPS) is an uncommon disease, making up 10-15 percent of all soft tissue sarcomas. RPS consists of liposarcoma, leiomyosarcoma and unclassified soft tissue sarcoma. Among them, liposarcoma is the most common type. Dedifferentiated liposarcomas have a poorer progress because they feature a higher metastatic, local recurrence rate and mortality.
Case report: A 68-year-old female patient first presented an evident drop of weight in months. A heterogeneous huge tumor was found in the left retroperitoneal space via non-enhanced abdominal CT. The tumor contributed mass effect on adjacent organs and structures, with equivocal left kidney outline. Enhanced kidney MRI illustrated its hypervascular content and clear border. Radical excision was performed via open approach. The mass was 25cm in lengh and weighed about 5kg. Grossly, it accompanies a compressed but invasion-free kidney. The diagnosis of dedifferentiated liposarcoma was made, and focally involved margin was identified.
Discussion: The average annual incidence of retroperitoneal sarcomas was 2.7/million. RPS seldom induces symptoms until the tumor grows mass effect on adjacent organs. The tumor of our patient stands out as the compressed, yet invasion-free left kidney. Surgical resection is regarded as the only potential curative therapy. Due to the large size at presentation and wide extent of the tumor, it often results in limited resectability or positive margin. Important prognostic factors of retroperitoneal sarcoma involve surgical margin, tumor grade, differentiation, and histiologic subtype. Dedifferentiated liposarcoma has a worse prognosis. Positive gross margin implies a higher chance of local recurrence and mortality rate.