Detection of bowel cancer using urinary biomarkers

Background and study aims
Bowel cancer is diagnosed in 40,000 people each year in the UK. Early detection and treatment of bowel cancer is important as it improves survival. This has led to a “fast-track” system to speed up waiting times and access to hospital tests. Deciding who to test is a hard for GPs and hospital doctors because bowel symptoms are common and are not usually due to cancer. In addition, not all people with a bowel cancer develop symptoms. Therefore, at present the vast majority of patients are required to undergo testing. An internal camera examination of the large bowel (colonoscopy) is the best way to look at the large bowel. This is invasive, can be uncomfortable and needs strong laxatives to prepare the bowel. There is a risk of unplanned admission to hospital and surgery. This test is also expensive and the demand is increasing in the NHS. In the UK, 300,000 people a year are referred through the fast-track system for suspected bowel cancer. Over 90% of these have normal results, meaning they have undergone unpleasant testing that did not help them. It is now possible to look at natural chemicals, produced by normal bacteria that live in everybody’s bowel, to help diagnose bowel conditions. Bowel cancer alters the chemical “signature”. The aim of this study is to test the urine of 600 people referred by their GP to the fast-track pathway for these chemicals to see how good they are at predicting bowel cancer.
Who can participate?
Patients aged 18 and over, referred by their GP for fast-track assessment due to symptoms of colorectal cancer
What does the study involve?
Participants provide a urine sample when they attend the hospital for colonoscopy or CT scanning. Participants are also asked to complete a short questionnaire collecting demographic information and some data about lifestyle including smoking status, alcohol use and dietary habit (meat eating, vegetarian or vegan diet). From that point on their clinical pathway is unaffected by participation in the study and the results of the volatile compound testing are not be available to the clinical team. At the end of their investigations (maximum of 63 days), a member of the research team accesses patient notes to collect disease outcome data coded as cancer, polyp or normal. The participants receive treatment as normal judged on the clinical data available to the clinicians caring for them. The urine samples are sent for analysis at the University of the West of England. They are analysed using three separate machines to identify which of these machines is the best for use in a clinical setting, to take forward into a larger study. Data from the testing are then analysed along with the data about disease status in order to assess the sensitivity and reliability of the testing for the identification of patients at high risk of having colon cancer.

研究背景与研究目标
英国每年有4万人被诊断为肠癌。早期检出与治疗肠癌可提升患者生存率，为此当地建立了快速转诊系统以缩短等待时长、加快医院检查流程。对于全科医生（General Practitioner, GP）与医院医师而言，筛选适宜检测人群颇具挑战：肠道症状较为常见，但大多并非癌症所致；且并非所有肠癌患者都会出现症状。因此，当前绝大多数疑似患者均需接受检查。大肠内部摄像检查（colonoscopy）是检视大肠的最优手段，但该检查具有侵入性，可能引发不适，且需服用强效泻药清理肠道，还存在意外住院与手术的风险。此外，该检查成本高昂，且英国国民保健署（National Health Service, NHS）的相关需求正持续增长。英国每年有30万名疑似肠癌患者通过快速转诊系统接受评估，其中超过90%的检查结果为正常，这意味着他们接受了无获益的不适检查。
如今，借助人体肠道共生细菌产生的天然化学物质，已可辅助诊断肠道疾病，而肠癌会改变这类物质的化学特征谱。本研究旨在检测600名经全科医生转诊进入快速转诊通道的患者的尿液样本，分析其中的相关化学物质，以评估其预测肠癌的效能。

参与人群
年龄18岁及以上、因结直肠癌（colorectal cancer）症状经全科医生转诊接受快速评估的患者。

研究流程
参与者在前往医院接受结肠镜检查或CT扫描时提供尿液样本，同时需填写一份简短问卷，内容涵盖人口统计学信息，以及吸烟状态、饮酒习惯、饮食结构（肉食、素食或纯素饮食）等生活方式相关数据。此后，参与者的临床诊疗路径不会因本研究的参与情况受到影响，临床团队也无法获取挥发性化合物检测的结果。在所有检查完成后（最长耗时不超过63天），研究团队成员将查阅患者病历，收集编码为癌症、息肉（polyp）或正常的疾病转归数据。参与者将根据接诊医师掌握的临床数据接受常规治疗。
尿液样本将被送往西英格兰大学（University of the West of England）进行分析，研究人员将使用三台独立设备开展检测，以确定哪台设备最适合应用于临床场景，为后续开展更大规模的研究奠定基础。随后，研究人员将结合检测数据与疾病状态数据开展分析，以评估该检测方法识别结直肠癌高风险患者的灵敏度与可靠性。