Lin Otto S, Gerson Lauren B, Soon Maw-Soan, Schembre Drew B, Kozarek Richard A
Gastroenterology Section, Virginia Mason Medical Center, Seattle, WA 98101, USA.
Arch Intern Med. 2005 Feb 28;165(4):382-90. doi: 10.1001/archinte.165.4.382.
Most guidelines for colorectal cancer screening do not consider distal hyperplastic polyps (HPs) to be markers for proximal colon neoplasia. However, many studies have shown an increased risk of proximal neoplasia (PN) in patients with distal HPs. We performed a systematic review to assess the association between distal HPs and PN.
We identified studies that compared the prevalence of PN and proximal advanced neoplasia in patients with distal HPs vs controls. Two masked investigators extracted data on individuals with distal HPs, distal adenomas, or no distal polyps. Using the DerSimonian and Laird method, we calculated summary risk ratios. Extensive subgroup analysis was performed.
The prevalence of PN and proximal advanced neoplasia in persons with distal HPs was 26.0% and 4.4%, respectively. In studies comparing the risk of PN in patients with distal HPs vs those with no distal polyps, the summary risk ratio was 1.81 (95% confidence interval, 1.20-2.73). However, this increased risk disappeared if only high-quality studies on screening patients were considered. The risk ratio was 0.69 (95% confidence interval, 0.60-0.80) when comparing the risk of PN in those with distal HPs vs those with distal adenomas.
Overall, patients with distal HPs have an intermediate risk of PN compared with those with distal adenomas or no distal polyps; however, in asymptomatic screening individuals, there is no increased risk of PN or proximal advanced neoplasia. The discovery of HPs on screening flexible sigmoidoscopy should not automatically prompt follow-up colonoscopy.
大多数结直肠癌筛查指南并不认为远端增生性息肉（HP）是近端结肠肿瘤的标志物。然而，许多研究表明，远端HP患者发生近端肿瘤（PN）的风险增加。我们进行了一项系统评价，以评估远端HP与PN之间的关联。
我们确定了比较远端HP患者与对照组中PN和近端进展期肿瘤患病率的研究。两名盲法研究者提取了远端HP、远端腺瘤或无远端息肉患者的数据。使用DerSimonian和Laird方法，我们计算了汇总风险比。进行了广泛的亚组分析。
远端HP患者中PN和近端进展期肿瘤的患病率分别为26.0%和4.4%。在比较远端HP患者与无远端息肉患者PN风险的研究中，汇总风险比为1.81（95%置信区间，1.20 - 2.73）。然而，如果仅考虑对筛查患者的高质量研究，这种增加的风险就会消失。比较远端HP患者与远端腺瘤患者PN风险时，风险比为0.69（95%置信区间，0.60 - 0.80）。
总体而言，与远端腺瘤患者或无远端息肉患者相比，远端HP患者发生PN的风险处于中等水平；然而，在无症状筛查个体中，PN或近端进展期肿瘤的风险并未增加。在筛查乙状结肠镜检查中发现HP不应自动促使进行后续结肠镜检查。
