Postgraduate Program in Surgical Sciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
Postgraduate Program in Epidemiology, Department of Statistics, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
Int J Colorectal Dis. 2023 Sep 15;38(1):230. doi: 10.1007/s00384-023-04524-4.
Anal bleeding is a frequent complaint in the coloproctological practice. Although usually associated with common anorectal disorders, it may represent a sign of an occult colorectal carcinoma. Our purpose was to evaluate the accuracy of the colonoscopy for detection of neoplastic lesions in patients under 50 years of age with rectal bleeding.
This systematic review and meta-analysis searched publications in PubMed, Web of Science, and Cochrane Library databases up to August, 2023. Cross-sectional and case-control studies including patients under 50 years with rectal bleeding evaluated by colonoscopy were included. Primary outcome was prevalence of neoplastic lesions (adenomas and adenocarcinomas). Secondary outcomes were prevalence of those lesions according to age and anatomic location. The study was registered on PROSPERO (CRD42021257859) on July 5, 2021.
Nine studies comprising 4162 patients were analyzed. A total of 398 patients with adenomas and 40 patients with adenocarcinoma were identified. Prevalence of neoplastic lesions (adenomas and carcinomas) was 10%. In patients under 40 years, the prevalence of neoplastic lesions was 7% (6% of adenomas, 1% of carcinomas). Among patients aged 40-50 years the prevalence was 15%, 14%, and 1%, respectively. Most lesions (71%) were located distally to splenic flexure.
About 10% of patients under 50 years with anal bleeding will have a neoplastic lesion detected through colonoscopy. The greatest benefit of the procedure is observed between 40 and 50 years. Almost 30% of the neoplastic lesions were found in the proximal colon and could not be detected without the performance of a complete colonoscopy.
肛门出血是肛肠病学实践中的常见主诉。尽管通常与常见的肛门直肠疾病相关，但它也可能是隐匿性结直肠癌的征象。我们的目的是评估结肠镜检查在 50 岁以下直肠出血患者中对肿瘤性病变的检测准确性。
本系统评价和荟萃分析检索了截至 2023 年 8 月在 PubMed、Web of Science 和 Cochrane Library 数据库中的出版物。纳入了年龄在 50 岁以下、接受结肠镜检查评估的直肠出血患者的横断面和病例对照研究。主要结局为肿瘤性病变（腺瘤和腺癌）的检出率。次要结局为按年龄和解剖部位划分的这些病变的检出率。该研究于 2021 年 7 月 5 日在 PROSPERO（CRD42021257859）上注册。
共分析了 9 项纳入 4162 例患者的研究。共发现 398 例腺瘤患者和 40 例腺癌患者。肿瘤性病变（腺瘤和癌）的检出率为 10%。40 岁以下患者的肿瘤性病变检出率为 7%（6%为腺瘤，1%为癌）。40-50 岁患者的检出率分别为 15%、14%和 1%。大多数病变（71%）位于脾曲远端。
50 岁以下肛门出血患者中约有 10%通过结肠镜检查可发现肿瘤性病变。该检查的最大获益见于 40-50 岁之间。近 30%的肿瘤性病变位于近端结肠，如果不进行完整的结肠镜检查，这些病变可能无法被发现。
