目的： 对老年病人手术切除原发性腹膜后软组织肉瘤（retroperitoneal sarcoma, RPS），分析术后并发症发生的危险因素。方法： 回顾性队列研究2009年7月至2020年12月中山医院软组织肉瘤多学科团队手术切除老年病人的原发性RPS。使用Logistic回归分析寻找术后并发症发生的危险因素。结果： 入组98例，男54例，女44例，26例（26.5%）年龄≥70岁。术后5年总生存率为61.2%（60例）（95%CI：49.1~73.7）。78例（79.6%）肿瘤负荷>10 cm，87例（88.8%）肿瘤为单病灶。其中高分化脂肪肉瘤35例（35.7%），去分化脂肪肉瘤31例（31.6%），平滑肌肉瘤15例（15.3%）。96例（98.0%）病人为根治性手术切除，54例（55.1%）病人联合脏器切除数>1个。总体55例（56.1%）发生术后并发症，16例（16.3%）发生严重并发症。4例（4.1%）术后死亡。多因素分析提示肿瘤负荷≥10 cm（OR=4.597，P=0.012）及联合脏器切除数>1个（OR=4.858，P=0.003）是老年RPS病人发生术后并发症的独立危险因素。结论： 手术仍是原发性RPS老年病人的首选治疗方式，但应在高流量医院开展。

Objective: To analyze the risk factors for postoperative complications of the elderly patients with primary retroperitoneal sarcoma(RPS). Methods: A retrospective cohort study was performed for elderly patients with primary RPS treated by soft tissue sarcoma multidisciplinary team Zhongshan Hospital from July 2009 to December 2020. Logistic regression analysis was used to find risk factors for postoperative complications. Results: A total of 98 cases were enrolled including male 54 cases and female 44 cases with 26 cases (26.5%) of age 70 years or older. Five-year overall survival following surgery was 61.2% (60 cases with 95% confidence interval, 49.1-73.7). Seventy-eight cases (79.6%) had tumor burden greater than 10 cm, and 87 cases (88.8%) with single lesion. There were 35 cases (35.7%) with well-differentiated liposarcoma, 31 cases (31.6%) with dedifferentiated liposarcoma, and 15 cases (15.3%) with leiomyosarcoma. A total of 96 cases(98.0%) underwent radical resection and 54 cases (55.1%) had more than one organ resected. The postoperative complications were found 55 cases (56.1%) and severe complications 16 cases (16.3%). Four cases (4.1%) died postoperatively. It was shown by multivariate analysis that both tumor burden greater than 10 cm (OR=4.597, P=0.012) and more than one organ resected (OR=4.858, P=0.003) were independent risk factors for postoperative complications in elderly patients with RPS. Conclusions: Operative treatment remained the preferred type for elderly cases with primary RPS and the surgery should be completed in high-flow centers of RPS.