肌肉减少症是以肌肉体积减少、肌力下降和肌肉功能减退为主要特征的临床综合征。肌肉减少症作为一个独立 的疾病体已成为近几年研究的热点，其在肿瘤患者中的地位越来越受到临床医生的重视。肌肉减少症是肿瘤恶病质的一个 重要特征，严重影响患者的生活质量和降低患者的生存期。在肿瘤患者中，发生肌肉减少症的几个主要因素包括：①高耗能； ②厌食；③炎症；④代谢不平衡。为了解肌肉减少症与肿瘤化疗之间的关系，我们从以下几个方面进行综述：肌肉减少症 在肿瘤患者中如何诊断；肌肉减少症在肿瘤患者中的发病率如何；在肿瘤患者治疗中，肌肉减少症与化疗药物之间的关系 如何；肌肉减少症对肿瘤患者预后的影响如何；肌肉减少症的干预措施及其对肿瘤患者治疗结局的影响。随着对肌肉减少 症在肿瘤患者中研究的深入，肿瘤学专家可以借鉴目前研究取得的结果应用于临床，根据每个患者的具体情况制定出个体 化的用药方案、营养治疗或物理辅助治疗策略等，最终为改善患者的预后和提高其生活质量服务。

 Sarcopenia is considered as a clinical syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength, and impaired muscular function. Sarcopenia has recently emerged as a new condition and more recently research has focused on cancer patients who appear to be especially exposed to this risk. Sarcopenia has received great attention by clinicians in the oncology field. Sarcopenia is the major feature of cancer cachexia, and is associated with reduced quality of life and survival. There are several reasons for muscle mass depletion in cancer patients, such as higher energy expenditure, anorexia, inflammation and unbalanced cancer metabolism. To explore the relationship between sarcopenia and cancer chemotherapy, purpose of this review is to define the diagnosis of sarcopenia in cancer patients, the prevalence of sarcopenia in cancer patients, its role in leading to chemotherapy toxicity and its effect on the prognosis in cancer patients. Finally, the review also aims to describe the current approaches to restore the muscle mass and the effects on the therapy in cancer patients.  Recent researches has allowed the oncologist to evaluate the muscle mass and to collect many data on the prevalence of sarcopenia and its clinical consequences. The oncologist should coordinate this multimodal approach by selecting priorities and sequences of treatments and then involving a nutrition health care professional or a physical therapist depending on the condition of the single cancer patient and improve the outcome of the cancer patients.