Division of Geriatrics, Department of Internal Medicine, Istanbul Medical School, Istanbul University, Capa, 34093, Istanbul, Turkey.
Department of Radiation Oncology, Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey.
Aging Clin Exp Res. 2022 Aug;34(8):1747-1759. doi: 10.1007/s40520-022-02085-0. Epub 2022 Feb 15.
Previous studies have evaluated the prognostic effects of sarcopenia in cancer patients receiving various treatments, including chemotherapy and surgery, but few studies have focused on radiotherapy (RT).
We aimed to investigate the prevalence of sarcopenia and the relationship between sarcopenia and outcomes in older cancer patients who underwent RT without chemotherapy.
A systematic review of the literature was conducted in Pubmed/Medline and Cochrane databases in September 2021. We used the search terms and medical subject heading terms "sarcopenia," "low muscle mass (LMM)," "low muscle strength," "LMM and low muscle strength," "LMM and low muscle strength and low physical performance," and "RT." Outcomes were overall survival (OS), progression-free survival, non-cancer death, cancer death, disease-specific survival, local failure-free survival, distant failure-free survival, and RT-related toxicities.
Among 460 studies, 8 studies were eligible for inclusion. The prevalence of sarcopenia was between 42.8% and 72%. Sarcopenia was not associated with OS or OS at 3 years in seven studies in which it was defined as the presence of LMM, while it was related in one study, in which it was defined as the concomitant presence of LMM and muscle strength/function.
There was heterogeneity between the studies because there was diversity in their inclusion criteria, definition and assessment methods used for detection of sarcopenia, considered cutoffs for low muscle mass and strength, cross-sectional locations on imaging to assess muscle mass and included covariates. The discrepancy in the results of the studies may also result from the variations in diagnoses, sample sizes, and treatment modalities. The low number of included studies and a small number of patients in each study limited generalizability.
Sarcopenia may be a prognostic factor, especially in OS when low muscle strength/function is integrated into its definition. We suggest that clinicians focus on muscle strength/function while considering sarcopenia and its association with cancer and RT-related outcomes.
先前的研究已经评估了在接受包括化疗和手术在内的各种治疗的癌症患者中，肌肉减少症的预后影响，但很少有研究关注放射治疗（RT）。
我们旨在调查未接受化疗的接受 RT 的老年癌症患者中肌肉减少症的流行情况以及其与结局之间的关系。
我们于 2021 年 9 月在 Pubmed/Medline 和 Cochrane 数据库中进行了文献的系统性回顾。我们使用了以下检索词和医学主题词：“肌肉减少症”、“低肌肉量（LMM）”、“低肌肉力量”、“LMM 和低肌肉力量”、“LMM 和低肌肉力量和低身体机能”以及“RT”。结局为总生存期（OS）、无进展生存期、非癌症死亡、癌症死亡、疾病特异性生存期、局部失败无复发生存期、远处失败无复发生存期和 RT 相关毒性。
在 460 项研究中，有 8 项研究符合纳入标准。肌肉减少症的流行率在 42.8%至 72%之间。在其中 7 项将 LMM 定义为肌肉减少症的研究中，肌肉减少症与 OS 或 3 年 OS 无关，而在其中 1 项将 LMM 与肌肉力量/功能并存定义为肌肉减少症的研究中，肌肉减少症与 OS 相关。
由于纳入标准、用于检测肌肉减少症的定义和评估方法、肌肉质量和力量的低值截断、影像学上评估肌肉质量的横截面积位置以及纳入的协变量存在差异，因此研究之间存在异质性。研究结果的差异也可能是由于诊断、样本量和治疗方式的变化所致。纳入研究的数量较少，每项研究中的患者数量较少，限制了研究结果的普遍性。
肌肉减少症可能是一个预后因素，尤其是在将低肌肉力量/功能纳入其定义时，与 OS 相关。我们建议临床医生在考虑肌肉减少症及其与癌症和 RT 相关结局的关系时，关注肌肉力量/功能。
