Adipose tissue density on CT as a prognostic factor in patients with cancer: a systematic review

Predicting oncologic outcomes is essential for optimizing the treatment for patients with cancer. This review examines the feasibility of using Computed Tomography (CT) images of fat density as a prognostic factor in patients with cancer. A systematic literature search was performed in PubMed, Embase and Cochrane up to March 2020. All studies that mentioned using subcutaneous or visceral adipose tissue (SAT and VAT, respectively) CT characteristics as a prognostic factor for patients with cancer were included. The primary endpoints were any disease-related outcomes in patients with cancer. After screening 1043 studies, ten studies reporting a total of 23 – ten for SAT and thirteen for VAT – comparisons on survival, tumor recurrence and postsurgical infection were included. All ten studies included different types of malignancy: six localized, two metastatic disease, and two both. Five different anatomic landmarks were used to uniformly measure fat density on CT: lumbar (L)4 (<i>n</i> = 4), L3 (<i>n</i> = 2), L4-L5 intervertebral space (<i>n</i> = 2), L5-S1 intervertebral space (<i>n</i> = 1), and the abdomen (<i>n</i> = 1). Overall, six of ten SAT comparisons (60%) and six of thirteen VAT comparisons (46%) reported a significant (<i>p</i> This review may support the feasibility of using SAT or VAT on CT as a prognostic tool for patients with cancer in predicting adverse outcomes such as survival and tumor recurrence. Future research should standardize radiologic protocol in prospective homogeneous series of patients on each cancer diagnosis group in order to establish accurate parameters to help physicians use CT scan defined characteristics in clinical practice.

预测肿瘤相关结局对于优化癌症患者的治疗方案至关重要。本综述探讨了以脂肪密度的计算机断层扫描（Computed Tomography，CT）图像作为癌症患者预后因素的可行性。本研究于2020年3月前在PubMed、Embase及Cochrane数据库中开展了系统性文献检索。所有提及将皮下脂肪组织（subcutaneous adipose tissue, SAT）或内脏脂肪组织（visceral adipose tissue, VAT）的CT特征作为癌症患者预后因素的研究均被纳入。本研究的主要结局指标为癌症患者的各类疾病相关结局。在筛选1043项研究后，最终纳入10项研究，共包含23组比较——其中皮下脂肪组织相关比较10组、内脏脂肪组织相关比较13组——比较内容涵盖生存情况、肿瘤复发与术后感染。这10项研究均纳入了不同类型的恶性肿瘤：6项为局限性恶性肿瘤，2项为转移性恶性肿瘤，另有2项同时包含上述两类肿瘤。研究采用了5种不同的解剖标志来统一测量CT图像中的脂肪密度：第4腰椎（L4，n=4）、第3腰椎（L3，n=2）、L4-L5椎间隙（n=2）、L5-S1椎间隙（n=1）以及腹部（n=1）。总体而言，10组皮下脂肪组织比较中有6组（60%）、13组内脏脂肪组织比较中有6组（46%）报告了具有统计学意义的（p。本综述结果表明，利用CT图像中的皮下脂肪组织或内脏脂肪组织特征作为癌症患者预后工具，预测生存情况不佳、肿瘤复发等不良结局具备可行性。未来研究应针对各癌症诊断组的前瞻性同质患者队列，统一影像学检查方案，以确立精准的参数标准，帮助临床医师将CT扫描定义的特征应用于临床实践。