Forjaz de Lacerda Gonçalo, Kelly Scott P, Bastos Joana, Castro Clara, Mayer Alexandra, Mariotto Angela B, Anderson William F
Division of Cancer Control and Population Sciences, National Cancer Institute, Rockville, MD, USA; Azores Region Cancer Registry, Azores Oncological Centre, Portugal.
Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD, USA.
Cancer Epidemiol. 2018 Jun;54:12-18. doi: 10.1016/j.canep.2018.03.003. Epub 2018 Mar 13.
Female breast cancer incidence rates have been increasing in Portugal for years. We, therefore, conducted the first nationwide breast cancer study to assess regional differences.
Cases were obtained from population-based cancer registries covering the country's Mainland (South, North, Centre), as well as the two Autonomous Regions (Azores and Madeira), for the time-period 1998 through 2011. Analyses were restricted to ages 30-84 years and stratified by region. We used the age-period-cohort (APC) framework to complement standard descriptive techniques and to forecast future trends. Estimable APC parameters included net drift, longitudinal age-specific incidence rate curves, and fitted age-specific incidence rate ratios.
There were 71 545 breast cancer cases diagnosed in Portugal at ages 30-84 years from 1998 to 2011. The South presented the highest age-standardized rate (155.8/100 000), while the North presented the fastest rate of increase (3.6%/year). Age-specific statistical interactions were observed between regions. Younger women in the North revealed a decreased risk of developing breast cancer compared to women from the same age group in the South and Centre, while that risk was reversed in older women (p < 0.05). We estimate that from 2014 onwards, the North might rank first among all regions.
The variant patterns observed could be due to a combination of different screening practices and/or exposure to risk factors across regions. Disease heterogeneity among younger and older women may also explain part of the differences in age-specific rates. These results justify continued monitoring of breast cancer incidence by region.
多年来，葡萄牙女性乳腺癌发病率一直在上升。因此，我们开展了首次全国性乳腺癌研究，以评估地区差异。
病例来自覆盖该国大陆（南部、北部、中部）以及两个自治区（亚速尔群岛和马德拉群岛）的基于人群的癌症登记处，时间跨度为1998年至2011年。分析仅限于30 - 84岁年龄组，并按地区分层。我们使用年龄 - 时期 - 队列（APC）框架来补充标准描述性技术，并预测未来趋势。可估计的APC参数包括净漂移、纵向年龄别发病率曲线以及拟合的年龄别发病率比。
1998年至2011年期间，葡萄牙30 - 84岁年龄组中有71545例乳腺癌病例被诊断。南部的年龄标准化发病率最高（155.8/100000），而北部的发病率增长最快（每年3.6%）。各地区之间观察到年龄特异性统计交互作用。与南部和中部同年龄组的女性相比，北部年轻女性患乳腺癌的风险降低，而老年女性则相反（p < 0.05）。我们估计，从2014年起，北部可能在所有地区中排名第一。
观察到的不同模式可能是由于各地区不同的筛查做法和/或风险因素暴露的综合作用。年轻和老年女性之间的疾病异质性也可能解释了年龄别发病率差异的部分原因。这些结果证明有必要继续按地区监测乳腺癌发病率。
