Baseline sarcopenia and postoperative changes in muscle mass are independently associated with overall survival (OS) in patients with metastatic renal cell carcinoma (mRCC) undergoing cytoreductive nephrectomy (CN). Here we examine the relationships between preoperative (baseline), postoperative changes in muscle quantity, and survival outcomes following CN as determined by linear segmentation, a clinic-friendly tool that rapidly estimates muscle mass. Our nephrectomy database was reviewed for patients with metastatic disease who underwent CN for RCC. Linear segmentation of the bilateral psoas/paraspinal muscles was completed for baseline imaging within 60 days of surgery and imaging 30 to 365 days postoperatively. Kruskal-Wallis for numerical and Fisher's exact test for categorical variables were used to test for differences between groups according to percent change in linear muscle index (LMI, cm/m). Multivariable Cox proportional hazards models evaluated associations between LMI percent change and cancer-specific (CSM) and all-cause mortality (ACM). Kaplan Meier curves estimated cancer-specific (CSS) and overall survival (OS). From 2004-2020, 205 patients were included of whom 52 demonstrated stable LMI (25.4%; LMI change < 5% [0Δ]), 60 increase (29.3%; LMI +5% [+Δ]), and 92 decrease (44.9%; LMI -5% [-Δ]). Median time from baseline imaging to surgery was 18 days, and time from surgery to postoperative imaging was 133 days. Median CSS and OS were highest among patients with 0Δ LMI (CSS: 133.6 [0Δ] vs. 61.9 [+Δ] vs. 37.4 [-Δ] months; 0018 || OS: 67.2 [0Δ] vs. 54.8 [+Δ] vs. 29.5 [-Δ] months; 0007). Stable LMI was a protective factor for CSM (HR 0.48; 024) and ACM (HR 0.59; 040) on multivariable analysis. Change in muscle mass after CN, as measured by the linear muscle segmentation technique, is independently associated with OS and CSS in patients following CN. Of note, lack of change was associated with longer survival.

中文翻译：

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转移性肾细胞癌的线性肌肉分割：临床友好估计的变化可预测减瘤性肾切除术后的生存率

接受减瘤性肾切除术 (CN) 的转移性肾细胞癌 (mRCC) 患者的基线肌少症和术后肌肉质量变化与总生存期 (OS) 独立相关。在这里，我们检查了术前（基线）、术后肌肉数量变化和 CN 后生存结果之间的关系，线性分割是一种快速估计肌肉质量的临床友好工具。我们对因 RCC 接受 CN 治疗的转移性疾病患者的肾切除数据库进行了审查。双侧腰肌/椎旁肌的线性分割在手术后 60 天内完成基线成像，并在术后 30 至 365 天进行成像。使用 Kruskal-Wallis 数值检验和 Fisher 精确检验分类变量，根据线性肌肉指数（LMI，cm/m）的百分比变化来检验组间差异。多变量 Cox 比例风险模型评估了 LMI 百分比变化与癌症特异性 (CSM) 和全因死亡率 (ACM) 之间的关联。 Kaplan Meier 曲线估计了癌症特异性 (CSS) 和总生存期 (OS)。从 2004 年到 2020 年，纳入了 205 名患者，其中 52 名患者 LMI 稳定（25.4%；LMI 变化 < 5% [0Δ]），60 名患者 LMI 增加（29.3%；LMI +5% [+Δ]），92 名患者 LMI 下降（44.9%）。 %；LMI -5% [-Δ])。从基线成像到手术的中位时间为 18 天，从手术到术后成像的时间为 133 天。中位 CSS 和 OS 在 0Δ LMI 患者中最高（CSS：133.6 [0Δ] vs. 61.9 [+Δ] vs. 37.4 [-Δ] 个月；0018 || OS：67.2 [0Δ] vs. 54.8 [+Δ] 个月vs. 29.5 [-Δ] 个月；0007)。在多变量分析中，稳定的 LMI 是 CSM（HR 0.48；024）和 ACM（HR 0.59；040）的保护因素。 CN 后肌肉质量的变化（通过线性肌肉分割技术测量）与 CN 后患者的 OS 和 CSS 独立相关。值得注意的是，缺乏变化与更长的生存期有关。