Bright C J, Rea D W, Francis A, Feltbower R G
Centre for Childhood Cancer Survivor Studies, Institute Applied Health Research, Robert Aitken Building, University of Birmingham, Birmingham B15 2TT, UK.
Cancer Research UK Clinical Trials Unit (CRCTU), Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham B15 2TT, UK.
Cancer Epidemiol. 2016 Oct;44:186-194. doi: 10.1016/j.canep.2016.08.019.
UK breast cancer incidence rates suggest that upper outer quadrant (UOQ) cancers have risen disproportionately compared with other areas over time. We aimed to provide a comparison of the trend in quadrant-specific breast cancer incidence between the United States (US) and England, and determine whether a disproportionate UOQ increase is present.
Surveillance Epidemiology and End Results (SEER) cancer registry data were obtained on 630,007 female breast cancers from 1975 to 2013. English cancer registry data were obtained on 1,121,134 female breast cancers from 1979 to 2013. Temporal incidence changes were analysed using negative binomial regression. Interaction terms determined whether incidence changes were similar between sites.
English breast cancer incidence in the UOQ rose significantly from 13% to 28% from 1979 to 2013 whereas no significant increase was observed among SEER data. The significant interaction between quadrant and year of diagnosis (p<0.001) in both SEER and English data indicates that breast cancer incidence in each quadrant changed at a different rate. Incidence in the UOQ rose disproportionately compared to the nipple (SEER IRR=0.81, p<0.001; England IRR=0.78, p<0.001) and axillary tail (SEER IRR=0.87, p=0.018; England IRR=0.69, p<0.001) in both SEER and England. In addition, incidence rose disproportionately in the UOQ compared to non-site-specific tumours in England (Overlapping lesions IRR=0.81, p=0.002; NOS IRR=0.78, p<0.001). The proportion of non-site-specific tumours was substantially higher in England than SEER throughout the study period (62% in England; 39% in SEER).
Breast cancer incidence in the UOQ increased disproportionately compared to non-site-specific tumours in England but not in SEER, likely due to the decrease in non-site-specific tumours observed in England over time. There may be real differences in incidence between the two countries, possibly due to differences in aetiology, but is much more likely to be an artefact of changing data collection methods and improvements in site coding in either country.
英国乳腺癌发病率数据显示，随着时间推移，乳腺上外象限（UOQ）癌症发病率的上升幅度高于其他区域。我们旨在比较美国和英国特定象限乳腺癌发病率的变化趋势，并确定UOQ发病率是否存在不成比例的增长。
获取了监测、流行病学和最终结果（SEER）癌症登记处1975年至2013年期间630,007例女性乳腺癌的数据。获取了英国癌症登记处1979年至2013年期间1,121,134例女性乳腺癌的数据。使用负二项回归分析发病率随时间的变化。交互项用于确定不同部位的发病率变化是否相似。
1979年至2013年期间，英国UOQ乳腺癌发病率从13%显著上升至28%，而SEER数据中未观察到显著增加。SEER和英国数据中象限与诊断年份之间的显著交互作用（p<0.001）表明，每个象限的乳腺癌发病率变化速率不同。在SEER和英国的数据中，与乳头（SEER发病率比值比[IRR]=0.81，p<0.001；英国IRR=0.78，p<0.001）和腋尾部（SEER IRR=0.87，p=0.018；英国IRR=0.69，p<0.001）相比，UOQ发病率的上升幅度不成比例。此外，在英国，与非特定部位肿瘤相比，UOQ发病率上升幅度不成比例（重叠病变IRR=0.81，p=0.002；非特定部位IRR=0.78，p<0.001）。在整个研究期间，英国非特定部位肿瘤的比例显著高于SEER（英国为62%；SEER为39%）。
与非特定部位肿瘤相比，英国UOQ乳腺癌发病率上升幅度不成比例，而SEER数据中并非如此，这可能是由于英国非特定部位肿瘤发病率随时间下降所致。两国发病率可能存在实际差异，可能是由于病因不同，但更有可能是数据收集方法变化以及两国部位编码改进导致的人为结果。
