Chemotherapy dosing is traditionally based on body surface area calculations; however, these calculations ignore separate tissue compartments, such as the lean body mass (LBM), which is considered a big pool of drug distribution. In our era, colorectal cancer patients undergo a plethora of computed tomography scans as part of their diagnosis, staging and monitoring, which could easily be used for body composition analysis and LBM calculation, allowing for personalised chemotherapy dosing. This systematic review aims to evaluate the effect of muscle mass on dose-limiting toxicity (DLT), among different chemotherapy regimens used in colorectal cancer patients. This review was carried out according to the PRISMA guidelines. MEDLINE and EMBASE databases were searched from 1946 to August 2019. The primary search terms were ‘sarcopenia’, ‘myopenia’, ‘chemotherapy toxicity’, ‘chemotherapy dosing’, ‘dose limiting toxicity’, ‘colorectal cancer’, ‘primary colorectal cancer’ and ‘metastatic colorectal cancer’. Outcomes of interest were – DLT and chemotoxicity related to body composition, and chemotherapy dosing on LBM. In total, 363 studies were identified, with 10 studies fulfilling the selection criteria. Seven studies were retrospective and three were prospective. Most studies used the same body composition analysis software but the chemotherapy regimens used varied. Due to marked study heterogeneity, quantitative data synthesis was not possible. Two studies described a toxicity cut-off value for 5-fluorouracil and one for oxaliplatin based on LBM. The rest of the studies showed an association between different body composition metrics and DLTs. Prospective studies are required with a larger colorectal cancer cohort, longitudinal monitoring of body composition changes during treatment, similar body composition analysis techniques, agreed cut-off values and standardised chemotherapy regimens. Incorporation of body composition analysis in the clinical setting will allow early identification of sarcopenic patients, personalised dosing based on their LBM and early optimisation of these patients undergoing chemotherapy.

化疗剂量传统上基于体表面积计算；然而，这些计算忽略了单独的组织区室，例如瘦体重 (LBM)，它被认为是一个大的药物分布池。在我们这个时代，结直肠癌患者接受大量计算机断层扫描作为诊断、分期和监测的一部分，这些扫描可以轻松用于身体成分分析和 LBM 计算，从而实现个性化的化疗剂量。本系统评价旨在评估肌肉质量对结直肠癌患者使用的不同化疗方案中剂量限制性毒性 (DLT) 的影响。本次审查是根据 PRISMA 指南进行的。从 1946 年到 2019 年 8 月搜索了 MEDLINE 和 EMBASE 数据库。主要搜索词是“肌肉减少症”、“肌减少症”、“化疗毒性”、“化疗剂量”、“剂量限制性毒性”、“结直肠癌”、“原发性结直肠癌”和“转移性结直肠癌”。感兴趣的结果是 – DLT 和与身体成分相关的化学毒性，以及 LBM 的化疗剂量。总共确定了 363 项研究，其中 10 项研究符合选择标准。七项研究是回顾性的，三项是前瞻性的。大多数研究使用相同的身体成分分析软件，但使用的化疗方案各不相同。由于显着的研究异质性，定量数据合成是不可能的。两项研究描述了基于 LBM 的 5-氟尿嘧啶和奥沙利铂的毒性临界值。其余研究表明，不同的身体成分指标与 DLT 之间存在关联。需要对更大的结直肠癌队列、治疗期间身体成分变化的纵向监测、类似的身体成分分析技术、商定的临界值和标准化的化疗方案进行前瞻性研究。在临床环境中结合身体成分分析将允许早期识别肌肉减少症患者，根据他们的 LBM 进行个性化给药，以及对这些接受化疗的患者进行早期优化。