Cancer Screening and Prevention Research Group, Department of Surgery and Cancer, Imperial College London, London, UK.
Department of Gastroenterology, University Hospital of North Tees, Stockton-on-Tees, UK.
Health Technol Assess. 2022 May;26(26):1-156. doi: 10.3310/OLUE3796.
Colonoscopy surveillance is recommended for some patients post polypectomy. The 2002 UK surveillance guidelines classify post-polypectomy patients into low, intermediate and high risk, and recommend different strategies for each classification. Limited evidence supports these guidelines.
To examine, for each risk group, long-term colorectal cancer incidence by baseline characteristics and the number of surveillance visits; the effects of interval length on detection rates of advanced adenomas and colorectal cancer at first surveillance; and the cost-effectiveness of surveillance compared with no surveillance.
A retrospective cohort study and economic evaluation.
Seventeen NHS hospitals.
Patients with a colonoscopy and at least one adenoma at baseline.
Long-term colorectal cancer incidence after baseline and detection rates of advanced adenomas and colorectal cancer at first surveillance.
Hospital databases, NHS Digital, the Office for National Statistics, National Services Scotland and Public Health England.
Cox regression was used to compare colorectal cancer incidence in the presence and absence of surveillance and to identify colorectal cancer risk factors. Risk factors were used to stratify risk groups into higher- and lower-risk subgroups. We examined detection rates of advanced adenomas and colorectal cancer at first surveillance by interval length. Cost-effectiveness of surveillance compared with no surveillance was evaluated in terms of incremental costs per colorectal cancer prevented and per quality-adjusted life-year gained.
Our study included 28,972 patients, of whom 14,401 (50%), 11,852 (41%) and 2719 (9%) were classed as low, intermediate and high risk, respectively. The median follow-up time was 9.3 years. Colorectal cancer incidence was 140, 221 and 366 per 100,000 person-years among low-, intermediate- and high-risk patients, respectively. Attendance at one surveillance visit was associated with reduced colorectal cancer incidence among low-, intermediate- and high-risk patients [hazard ratios were 0.56 (95% confidence interval 0.39 to 0.80), 0.59 (95% confidence interval 0.43 to 0.81) and 0.49 (95% confidence interval 0.29 to 0.82), respectively]. Compared with the general population, colorectal cancer incidence without surveillance was similar among low-risk patients and higher among high-risk patients [standardised incidence ratios were 0.86 (95% confidence interval 0.73 to 1.02) and 1.91 (95% confidence interval 1.39 to 2.56), respectively]. For intermediate-risk patients, standardised incidence ratios differed for the lower- (0.70, 95% confidence interval 0.48 to 0.99) and higher-risk (1.46, 95% confidence interval 1.19 to 1.78) subgroups. In each risk group, incremental costs per colorectal cancer prevented and per quality-adjusted life-year gained with surveillance were lower for the higher-risk subgroup than for the lower-risk subgroup. Incremental costs per quality-adjusted life-year gained were lowest for the higher-risk subgroup of high-risk patients at £7821.
The observational design means that we cannot assume that surveillance caused the reductions in cancer incidence. The fact that some cancer staging data were missing places uncertainty on our cost-effectiveness estimates.
Surveillance was associated with reduced colorectal cancer incidence in all risk groups. However, in low-risk patients and the lower-risk subgroup of intermediate-risk patients, colorectal cancer incidence was no higher than in the general population without surveillance, indicating that surveillance might not be necessary. Surveillance was most cost-effective for the higher-risk subgroup of high-risk patients.
Studies should examine the clinical effectiveness and cost-effectiveness of post-polypectomy surveillance without prior classification of patients into risk groups.
This trial is registered as ISRCTN15213649.
This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in ; Vol. 26, No. 26. See the NIHR Journals Library website for further project information.
息肉切除术后建议对某些患者进行结肠镜检查监测。2002 年英国监测指南将息肉切除术后患者分为低危、中危和高危，并为每个分类推荐了不同的监测策略。有限的证据支持这些指南。
根据基线特征和监测次数，检查每个风险组的长期结直肠癌发病率；研究间隔时间对首次监测时高级别腺瘤和结直肠癌检出率的影响；以及与不监测相比监测的成本效益。
回顾性队列研究和经济评估。
17 家 NHS 医院。
基线时进行结肠镜检查和至少有一个腺瘤的患者。
基线后结直肠癌的长期发病率和首次监测时高级别腺瘤和结直肠癌的检出率。
医院数据库、NHS Digital、国家统计局、苏格兰国家服务和英格兰公共卫生。
使用 Cox 回归比较存在和不存在监测时的结直肠癌发病率，并确定结直肠癌的危险因素。危险因素用于根据间隔时间将风险组分层为高风险和低风险亚组。我们通过间隔时间检查首次监测时高级别腺瘤和结直肠癌的检出率。通过比较每预防一例结直肠癌和每增加一个质量调整生命年的增量成本，评估监测与不监测的成本效益。
我们的研究包括 28972 名患者，其中 14401 名（50%）、11852 名（41%）和 2719 名（9%）分别被归类为低危、中危和高危。中位随访时间为 9.3 年。低危、中危和高危患者的结直肠癌发病率分别为每 100000 人年 140、221 和 366 例。低危、中危和高危患者中，进行一次监测就诊与结直肠癌发病率降低相关[风险比分别为 0.56（95%置信区间 0.39 至 0.80）、0.59（95%置信区间 0.43 至 0.81）和 0.49（95%置信区间 0.29 至 0.82）]。与一般人群相比，低危患者的结直肠癌发病率与不监测相似，高危患者的发病率更高[标准化发病率比分别为 0.86（95%置信区间 0.73 至 1.02）和 1.91（95%置信区间 1.39 至 2.56）]。对于中危患者，低危亚组（0.70，95%置信区间 0.48 至 0.99）和高危亚组（1.46，95%置信区间 1.19 至 1.78）的标准化发病率比值不同。在每个风险组中，高危亚组的监测每预防一例结直肠癌和每增加一个质量调整生命年的增量成本均低于低危亚组。高危患者高危亚组每增加一个质量调整生命年的增量成本最低，为 7821 英镑。
观察性设计意味着我们不能假设监测导致癌症发病率降低。一些癌症分期数据缺失，这给我们的成本效益估计带来了不确定性。
在所有风险组中，监测与结直肠癌发病率降低相关。然而，在低危患者和中危患者的低危亚组中，结直肠癌发病率并不高于无监测的一般人群，表明监测可能不是必要的。对于高危患者的高危亚组，监测的成本效益最高。
研究应检查没有预先对患者进行风险分组的情况下息肉切除术后监测的临床效果和成本效益。
本试验已在 ISRCTN 注册，注册号为 ISRCTN82004059。
本项目由英国国家卫生与保健优化研究所（NIHR）卫生技术评估计划资助，全文将在 ；第 26 卷，第 26 期。有关该项目的更多信息，请访问 NIHR 期刊库网站。
