School of Engineering, University of Warwick, Coventry CV4 7AL, UK.
Clinical Sciences Research Institute, University of Warwick, Coventry CV2 2DX, UK; Department of Gastroenterology, University Hospital Coventry and Warwickshire, Coventry CV2 2DX, UK.
Biosens Bioelectron. 2015 May 15;67:733-8. doi: 10.1016/j.bios.2014.10.044. Epub 2014 Oct 23.
Colorectal cancer is a leading cause of cancer death in the USA and Europe with symptoms that mimick other far more common lower gastrointestinal (GI) disorders. This difficulty in separating colorectal cancer from these other diseases has driven researchers to search for an effective, non-invasive screening technique. Current state-of-the-art method of Faecal Immunochemical Testing achieving sensitivity ~90%, unfortunately the take-up in the western world is low due to the low patient acceptability of stool samples. However, a wide range of cancers have been distinguished from each-other and healthy controls by detecting the gas/volatile content emanating patient biological media. Dysbiosis afforded by certain disease states may be expressed in the volatile content of urine - a reflection of the gut bacteria's metabolic processes. A new electronic nose instrument was developed at the University of Warwick to measure the gas/volatile content of urine headspace, based on an array of 13 commercial electro-chemical and optical sensors. An experimental setup was arranged for a cohort of 92 urine samples from patients of colorectal cancer (CRC), irritable bowel syndrome (IBS) and controls to be run through the machine. Features were extracted from response data and used in Linear Discriminant Analysis (LDA) plots, including a full 3-disease classification and one focussing on distinguishing CRC from IBS. The latter case was tested by the success of re-classification using an (n-1) K-nearest neighbour algorithm, showing 78% sensitivity and 79% specificity to CRC.
结直肠癌是美国和欧洲癌症死亡的主要原因，其症状与其他更为常见的下胃肠道（GI）疾病相似。这种将结直肠癌与其他疾病区分开来的困难促使研究人员寻找一种有效的、非侵入性的筛选技术。目前粪便免疫化学检测是最先进的方法，其灵敏度约为 90%，但由于患者对粪便样本的接受程度低，在西方世界的应用率较低。然而，通过检测患者生物介质散发的气体/挥发性物质，已经可以将广泛的癌症与彼此以及健康对照区分开来。某些疾病状态下的微生物失调可能会在尿液的挥发性物质中表现出来——这反映了肠道细菌的代谢过程。华威大学开发了一种新型电子鼻仪器，用于测量尿液顶空的气体/挥发性物质，该仪器基于 13 种商业电化学和光学传感器阵列。为 92 个来自结直肠癌（CRC）、肠易激综合征（IBS）和对照患者的尿液样本安排了一个实验装置，让这些样本通过仪器进行检测。从响应数据中提取特征，并用于线性判别分析（LDA）图，包括全 3 种疾病分类和一种专注于区分 CRC 和 IBS 的分类。后一种情况通过使用（n-1）最近邻算法对重新分类的成功进行了测试，对 CRC 的敏感性为 78%，特异性为 79%。
