Extremity liposarcoma represents 25% of extremity soft tissue sarcoma and has a better prognosis than liposarcoma occurring in other anatomic sites. The purpose of this study was to develop two nomograms for predicting the overall survival (OS) and cancer-specific survival (CSS) of patients with extremity liposarcoma. A total of 2170 patients diagnosed with primary extremity liposarcoma between 2004 and 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox analyses were performed to explore the independent prognostic factors and establish two nomograms. The area under the curve (AUC), C-index, calibration curve, decision curve analysis (DCA), Kaplan-Meier analysis, and subgroup analyses were used to evaluate the nomograms. Six variables were identified as independent prognostic factors for both OS and CSS. In the training cohort, the AUCs of the OS nomogram were 0.842, 0.841, and 0.823 for predicting 3-, 5-, and 8-year OS, respectively, while the AUCs of the CSS nomogram were 0.889, 0.884, and 0.859 for predicting 3-, 5-, and 8-year CSS, respectively. Calibration plots and DCA revealed that the nomogram had a satisfactory ability to predict OS and CSS. The above results were also observed in the validation cohort. In addition, the C-indices of both nomograms were significantly higher than those of all independent prognostic factors in both the training and validation cohorts. Stratification of the patients into high- and low-risk groups highlighted the differences in prognosis between the two groups in the training and validation cohorts. Age, sex, tumor size, grade, M stage, and surgery status were confirmed as independent prognostic variables for both OS and CSS in extremity liposarcoma patients. Two nomograms based on the above variables were established to provide more accurate individual survival predictions for extremity liposarcoma patients and to help physicians make appropriate clinical decisions.

中文翻译：

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用于预测四肢脂肪肉瘤患者总体生存率和癌症特异性生存率的线型图：一项基于人群的研究。

肢体脂肪肉瘤占肢体软组织肉瘤的25％，其预后要好于其他解剖部位的脂肪肉瘤。这项研究的目的是开发两个列线图，以预测四肢脂肪肉瘤患者的总体生存期（OS）和癌症特异性生存期（CSS）。从监测，流行病学和最终结果（SEER）数据库中提取了2004年至2015年之间共诊断为原发性肢端脂肪肉瘤的2170例患者。进行单因素和多因素Cox分析以探讨独立的预后因素并建立两个诺模图。曲线下面积（AUC），C指数，校准曲线，决策曲线分析（DCA），Kaplan-Meier分析和子组分析用于评估列线图。六个变量被确定为OS和CSS的独立预后因素。在训练队列中，用于预测3年，5年和8年OS的OS诺模图的AUC分别为0.842、0.841和0.823，而用于预测3年，5和8年的CSS诺模图的AUC分别为0.889、0.884和0.859。 3年，5年和8年CSS。校准图和DCA显示，列线图具有令人满意的预测OS和CSS的能力。在验证队列中也观察到了以上结果。此外，在训练和验证队列中，两个列线图的C指数均显着高于所有独立预后因素的C指数。将患者分为高风险组和低风险组，这突显了训练和验证队列中两组之间预后的差异。年龄，性别，肿瘤大小，分级，M分期和手术状态被确认为四肢脂肪肉瘤患者OS和CSS的独立预后变量。建立了基于上述变量的两个列线图，以为肢体脂肪肉瘤患者提供更准确的个体生存预测，并帮助医生做出适当的临床决策。