Eaden J A, Abrams K R, Mayberry J F
Gastrointestinal Research Unit, Leicester General Hospital, Gwendolen Road, Leicester LE5 4PW, UK.
Gut. 2001 Apr;48(4):526-35. doi: 10.1136/gut.48.4.526.
Controversy surrounds the risk of colorectal cancer (CRC) in ulcerative colitis (UC). Many studies have investigated this risk and reported widely varying rates.
A literature search using Medline with the explosion of references identified 194 studies. Of these, 116 met our inclusion criteria from which the number of patients and cancers detected could be extracted. Overall pooled estimates, with 95% confidence intervals (CI), of cancer prevalence and incidence were obtained using a random effects model on either the log odds or log incidence scale, as appropriate.
The overall prevalence of CRC in any UC patient, based on 116 studies, was estimated to be 3.7% (95% CI 3.2-4.2%). Of the 116 studies, 41 reported colitis duration. From these the overall incidence rate was 3/1000 person years duration (pyd), (95% CI 2/1000 to 4/1000). The overall incidence rate for any child was 6/1000 pyd (95% CI 3/1000 to 13/1000). Of the 41 studies, 19 reported results stratified into 10 year intervals of disease duration. For the first 10 years the incidence rate was 2/1000 pyd (95% CI 1/1000 to 2/1000), for the second decade the incidence rate was estimated to be 7/1000 pyd (95% CI 4/1000 to 12/1000), and in the third decade the incidence rate was 12/1000 pyd (95% CI 7/1000 to 19/1000). These incidence rates corresponded to cumulative probabilities of 2% by 10 years, 8% by 20 years, and 18% by 30 years. The worldwide cancer incidence rates varied geographically, being 5/1000 pyd in the USA, 4/1000 pyd in the UK, and 2/1000 pyd in Scandinavia and other countries. Over time the cancer risk has increased since 1955 but this finding was not significant (p=0.8).
Using new meta-analysis techniques we determined the risk of CRC in UC by decade of disease and defined the risk in pancolitics and children. We found a non-significant increase in risk over time and estimated how risk varies with geography.
溃疡性结肠炎（UC）患者患结直肠癌（CRC）的风险存在争议。许多研究对这一风险进行了调查，报告的发病率差异很大。
使用Medline进行文献检索，通过文献追溯共识别出194项研究。其中，116项符合我们的纳入标准，从中可以提取出患者数量和检测到的癌症病例数。根据情况，在对数优势比或对数发病率尺度上，使用随机效应模型获得癌症患病率和发病率的总体合并估计值及95%置信区间（CI）。
基于116项研究，估计任何UC患者中CRC的总体患病率为3.7%（95%CI 3.2 - 4.2%）。在这116项研究中，41项报告了结肠炎病程。据此得出的总体发病率为每1000人年病程3例（95%CI 每1000人年病程2至4例）。任何儿童的总体发病率为每1000人年病程6例（95%CI 每100人年病程3至13例）。在41项研究中，19项报告了按病程10年间隔分层的结果。在最初10年，发病率为每1000人年病程2例（95%CI 每1000人年病程1至2例），在第二个十年，发病率估计为每1000人年病程7例（95%CI 每1000人年病程4至12例），在第三个十年，发病率为每1000人年病程12例（95%CI 每1000人年病程7至19例）。这些发病率对应的10年累积概率为2%，20年为8%，30年为18%。全球癌症发病率在地理上存在差异，美国为每1000人年病程5例，英国为每1000人年病程4例，斯堪的纳维亚及其他国家为每1000人年病程2例。自1955年以来，癌症风险随时间有所增加，但这一发现无统计学意义（p = 0.8）。
使用新的荟萃分析技术，我们按疾病病程的十年确定了UC患者患CRC的风险，并明确了全结肠炎患者和儿童的风险。我们发现风险随时间无显著增加，并估计了风险如何随地域变化。
