Gatta G, Ciccolallo L, Capocaccia R, Coleman M P, Hakulinen T, Møller H, Berrino F
Istituto Nazionale per lo Studio e la Cura dei Tumori, Division of Epidemiology, Via Venezian 1, 1-20133 Milan, Italy.
Eur J Cancer. 2003 Oct;39(15):2214-22. doi: 10.1016/s0959-8049(03)00549-5.
A previous study has shown a lower survival for colorectal cancer in Europe than in the United States of America (USA). It is of interest to examine the extent to which anatomical location and morphological type influence this difference in colorectal cancer survival. We analysed survival for 151,244 European and 53,884 US patients diagnosed with colorectal cancer aged 15-99 years during the period of 1985-1989, obtained from 40 cancer registries that contribute to the EUROCARE study from 17 countries, and nine Surveillance, Epidemiology and End-Results (SEER) registries in the USA. Cases included in the analysis were first primary malignant tumours (ICD-O behaviour code 3 or higher). Relative survival was estimated to correct for competing causes of mortality. The Hakulinen-Tenkanen multiple regression approach was used to examine the prognostic impact of sub-site and ICD-O histology codes. Relative excess risks (RERs) derived from this approach estimate the extent to which the hazard of death differs from that in a reference region after adjustment for mortality in the general population. In order to explore geographical variation, we defined three groups of European registries within which survival rates were known to be broadly similar. The proportion of cases with unspecified sub-site was higher in Europe than the USA (10% versus 2%), but sub-site distributions were broadly similar in the two populations. With the exception of appendix, 5-year survival was 13-22% higher in the USA than in Europe for each anatomical sub-site. The proportion of non-microscopically-verified cases was higher in Europe than the USA (16 versus 3%). Adenocarcinomas arising in a polyp (ICD-O-2 8210, 8261, 8263) were more frequent in the USA than Europe (13 versus 2%). Five-year survival was higher in the USA than Europe for each morphological group, with the exception of non-microscopically-verified cases. When age, gender and sub-site were considered, RERs ranged from 1.52 to 2.40 for the European populations (with the USA as a reference). After inclusion of morphology codes, the range of RERs fell to between 1.28 and 1.86, mainly because of the high frequency of adenocarcinoma in polyps in the USA. This analysis suggests that the large survival advantage for colorectal cancer patients in the USA can only marginally be explained by differences in the distribution of sub-site and morphology. The main explanatory difference is the proportion of adenocarcinoma in polyps.
先前的一项研究表明，欧洲结直肠癌患者的生存率低于美国。探究结直肠癌生存率的这种差异在多大程度上受解剖部位和形态学类型的影响很有意义。我们分析了1985年至1989年期间151244例欧洲和53884例美国15至99岁确诊为结直肠癌患者的生存率，这些数据来自17个国家参与EUROCARE研究的40个癌症登记处，以及美国的9个监测、流行病学和最终结果（SEER）登记处。分析纳入的病例为原发性恶性肿瘤（ICD - O行为代码为3或更高）。估计相对生存率以校正竞争性死亡原因。采用哈库利宁 - 滕卡宁多元回归方法来检验亚部位和ICD - O组织学代码的预后影响。从该方法得出的相对超额风险（RER）估计了在调整一般人群死亡率后，死亡风险与参考地区相比的差异程度。为了探究地理差异，我们定义了三组欧洲登记处，已知其中生存率大致相似。欧洲未明确亚部位的病例比例高于美国（10%对2%），但两个群体中亚部位分布大致相似。除阑尾外，每个解剖亚部位美国的5年生存率比欧洲高13%至22%。欧洲未经显微镜证实的病例比例高于美国（16%对3%）。息肉中发生的腺癌（ICD - O - 2 8210、8261、8263）在美国比欧洲更常见（13%对2%）。每个形态学组美国的5年生存率都高于欧洲，未经显微镜证实的病例除外。当考虑年龄、性别和亚部位时，欧洲人群的RER范围为1.52至2.40（以美国为参考）。纳入形态学代码后，RER范围降至1.28至1.86之间，主要是因为美国息肉中腺癌的发生率很高。该分析表明，美国结直肠癌患者的巨大生存优势只能部分地由亚部位和形态学分布的差异来解释。主要的解释性差异是息肉中腺癌的比例。
