Objective: To compare the detection rate of advanced neoplasia and the number of people needing endoscopy in colorectal cancer screening giving at different starting age in population at high risk. Methods: Based on the screening project of early diagnosis and treatment of colorectal cancer in Jiashan county, Zhejiang province, two rounds of colorectal cancer screening were conducted between January 2007 and December 2020. After excluding participants who were not at high risk or had incomplete information, 27 130 participants and 31 205 participants were finally enrolled in round one and in round two, respectively. The spline analysis based on the generalized additive model was used to describe the trend of detection rate of advanced neoplasia with age. The detection rate and number of people needing endoscopy for the groups with starting age at 50, 45 and 40 years were calculated, and the differences in the detection rate were tested by χ2 goodness of fit test. Results: A total of 21 077 (77.69%) participants in round one and 25 249 (80.91%) participants in round two received endoscopy, in whom 1 097 (detection rate=52.05‰) and 1 151 (detection rate=45.59‰) had advanced neoplasia (cancers and advanced adenomas), respectively. The detection rate increased significantly with age, and the detection rate in round one were significantly higher than that in round two (P<0.05). The overall detection rates of advanced neoplasia for the groups with starting age at 50, 45 and 40 years were 61.11‰, 56.14‰ and 52.05‰ in round one, and 49.10‰, 46.75‰ and 45.59‰ in round two, respectively. The rates were significantly higher for the group with starting age at 50 years than that with starting age at 40 years in both round one and round two (P<0.05). The numbers of people needing endoscopy of advanced neoplasia for the groups with starting age at 50, 45 and 40 years were 17, 18, and 20 in round one, and 21, 22 and 22 in round two. Conclusions: The detection rate of advanced neoplasia increased with age. Starting screening at lower age might contribute to decreased detection rate and increased number of people needing endoscopy. However, the difference was limited.
目的： 比较不同筛查起始年龄对结直肠癌高危人群的进展期病变检出的影响。 方法： 基于浙江省嘉善县结直肠癌早诊早治筛查项目，以2007年1月至2020年12月两轮筛查中初筛阳性的结直肠癌高危人群为研究对象，剔除信息不全者后，最终分别纳入27 130例和31 205例。采用基于广义加性模型的样条分析拟合高危人群进展期病变检出率的年龄变化趋势。进一步计算50、45和40岁3种不同起始年龄的进展期病变检出率和需镜检人数，并采用χ2拟合优度检验比较检出率差异。 结果： 两轮筛查分别有21 077例（77.69%）和25 249例（80.91%）参与了肠镜检查，分别检出结直肠进展期病变（癌与进展期腺瘤）1 097例（52.05‰）和1 151例（45.59‰）。结直肠癌和进展期腺瘤的检出率均随年龄增长而显著增加（趋势检验P<0.05），且第一轮检出率显著高于第二轮（P<0.05）。分别以50、45和40岁为起始年龄的结直肠进展期病变检出率在第一轮筛查中依次为61.11‰、56.14‰和52.05‰，在第二轮中依次为49.10‰、46.75‰和45.59‰。χ2拟合优度检验表明，以40岁为起始年龄的进展期病变检出率显著低于以50岁为起始年龄的进展期病变检出率（P<0.05）。相应地，50、45和40岁3种起始年龄每检出1例进展期病变的需镜检人数在第一和第二轮筛查中分别为17、18、20人和21、22、22人。 结论： 结直肠进展期病变检出率随年龄增长而增大。因此，筛查起始年龄提前会使进展期病变检出率减小，但实际差异有限。.