Fecal occult blood test (FOBT) screening for colorectal cancer (CRC) is implemented in several countries. Approximately half of all FOBT‐positive persons have screen‐detected adenomas. Despite removal of these, patients with large/multiple adenomas have increased risk of later developing new advanced adenomas and CRC. International guidelines exist for colonoscopic surveillance following adenoma removal. These divide patients into low‐, intermediate‐ and high‐risk groups. We followed 711 FOBT‐positive patients with screening adenoma identified during population‐based CRC screening in two Danish counties in 2005–2006. As reference population, we included 1,240,348 persons in the same age group from the rest of Denmark not included in the screening. We estimated the long‐term CRC risk stratified by adenoma findings during screening and compared to the reference group. After 12 years follow‐up, the CRC incidence among all adenoma patients was 322 cases per 100,000 person‐years (95% confidence interval [CI]: 212–489) ranging from 251 (95% CI: 94–671) to 542 (95% CI: 300–978) cases per 100,000 person‐years in the low‐ and high‐risk groups, respectively. In the reference population, the CRC incidence was 244 (95% CI: 242–247) per 100,000. Patients with screen‐detected high‐risk adenomas after a positive FOBT had an almost doubled risk of CRC compared to the reference population (adjusted hazard ratio [aHR] 1.95, 95% CI: 1.08–3.51), and the incidence in those with no follow‐up visits was over 3.6 (aHR 3.64, 95% CI: 1.82–7.29) times the incidence in the reference population. The increased CRC risk could be controlled if high‐risk patients underwent follow‐up colonoscopy (aHR 0.87, 95% CI: 0.28–2.69).

中文翻译：

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经筛查的腺瘤后结直肠癌的长期风险：丹麦gFOBT阳性筛查队列的经验。

在多个国家/地区实施了针对大肠癌（CRC）的粪便潜血测试（FOBT）筛查。所有FOBT阳性患者中约有一半患有筛查腺瘤。尽管切除了这些腺瘤，但患有大/多个腺瘤的患者后来发生新的晚期腺瘤和CRC的风险增加。去除腺瘤后，存在用于结肠镜检查的国际指南。这些将患者分为低，中，高风险组。在2005-2006年间，我们追踪了丹麦两个县基于人群CRC筛查发现的711例FOBT阳性腺瘤筛查患者。作为参考人群，我们纳入了来自丹麦其他地区的相同年龄组的1,240,348人，但未包括在筛查中。我们估计了筛查过程中腺瘤的发现分层的长期CRC风险，并与参考组进行了比较。随访12年后，所有腺瘤患者的CRC发生率为每100,000人年322例（95％置信区间[CI]：212-489），范围从251（95％CI：94-671）到542（在低风险和高风险人群中，每100,000人年分别有95％CI：300-978）例。在参考人群中，CRC发生率为每100,000例244（95％CI：242–247）。与参考人群相比，FOBT阳性后筛查出的高危腺瘤患者发生CRC的风险几乎翻倍（调整后的危险比[aHR] 1.95，95％CI：1.08-3.51），而未进行筛查的高危腺瘤患者的发生率随访是参考人群发生率的3.6倍（aHR 3.64，95％CI：1.82-7.29）。