Effectiveness of Multi-target FIT-DNA Analysis as a Colorectal Cancer Screening Test

Colorectal cancer is one of the most common cancer in Hong Kong. In 2018, CRC accounted for 17.4%, 5,780 cases, of the total new cancers. CRC claimed 2,279 lives (15.8%) making it the second most deadly killer in the population. Since 2010, the Cancer Expert Working Group (CEWG) has recommended that asymptomatic average-risk individuals aged 50 to 75 years should consider one of the screening methods: fecal occult blood test (FOBT) every one to two years; OR flexible sigmoidoscopy every 5 years; OR colonoscopy every 10 years. However, it poses great challenges for large scale CRC screening using colonoscopy, such as bowel preparation difficulties, complications of procedure and poor compliance. ColoClear is intended for use as an adjunctive screening test for the detection of colorectal neoplasia associated DNA markers and for the presence of occult hemoglobin in human stool. It has the potential of increasing the sensitivity of detecting CRC as compared to FOBT or faecal immunochemical test (FIT), which detects the presence of hemoglobin in stool alone. A positive result may indicate the presence of colorectal cancer or pre-malignant colorectal neoplasia. ColoClear is not intended as a replacement for diagnostic colonoscopy. A positive result in ColoClear, as with any screening test, should be followed by colonoscopy. ColoClear is intended for colorectal cancer screening in average risk individuals: adults of either sex, 40 years or older, who are at high risk for colorectal cancer.结直肠癌（Colorectal cancer, CRC）是香港最常见的癌症之一。2018年，结直肠癌新发病例占香港所有新增癌症病例的17.4%，共计5780例；同年因结直肠癌离世的病例达2279例，占癌症总死亡人数的15.8%，成为香港人群中第二大致死性癌症杀手。 自2010年起，癌症专家工作组（Cancer Expert Working Group, CEWG）建议，50至75岁的无症状平均风险人群可考虑以下任一筛查方案：每1至2年进行粪便隐血试验（fecal occult blood test, FOBT）、每5年进行软式乙状结肠镜检查，或每10年进行结肠镜检查。然而，采用结肠镜开展大规模结直肠癌筛查面临诸多挑战，例如肠道准备难度大、操作相关并发症以及受试者依从性不佳等。 ColoClear是一款辅助筛查检测试剂，用于检测人类粪便中与结直肠肿瘤相关的DNA标志物以及隐血血红蛋白。相较于仅检测粪便中血红蛋白的粪便隐血试验（FOBT）或免疫法粪便隐血试验（faecal immunochemical test, FIT），ColoClear在结直肠癌检测敏感性上具备潜在优势。若检测结果呈阳性，可能提示存在结直肠癌或癌前结直肠肿瘤病变。ColoClear并非诊断性结肠镜检查的替代方案：与任何筛查检测一致，ColoClear结果呈阳性者需进一步接受结肠镜检查。本产品适用于结直肠癌平均风险人群的筛查，即40岁及以上的两性成人，属于结直肠癌高风险人群。