Introduction: Lung cancer incidence is higher among non‐Hispanic (NH) blacks than among the NH white and Hispanic populations in the United States. However, national cancer estimates may not always reflect the cancer burden in terms of disparities and incidence in small geographic areas, especially urban‐rural disparities. Moreover, there is a gap in the literature regarding rural‐urban disparities in terms of cancer histologic type. Methods: Using population‐based cancer registry data—Surveillance, Epidemiology and End Results and National Program of Cancer Registries data—we present age‐adjusted histologic rates and trends by race/ethnicity and residential county location at the time of first cancer diagnosis. Rate ratios were calculated to examine racial/ethnic differences in rates. Annual percent change was calculated to measure changes in rates over time. Results: We found that declines in squamous cell carcinoma are occurring fastest in metropolitan counties, whereas rates of adenocarcinoma increased fastest in counties nonadjacent to metropolitan areas. Further, although NH black men have increased lung cancer incidence compared with NH white and Hispanic men in all geographic locations, we found that the degree of the disparity increases with increasing rurality of residence. Finally, we discovered that among women whose lung cancer was diagnosed when they were younger than 55 years, the incidence of squamous cell carcinoma and adenocarcinoma was higher for NH blacks than for NH whites. Conclusions: Our results highlight disparities among NH blacks in nonadjacent rural areas. These findings may have significant impact for the implementation of smoking cessation and lung cancer screening programs.

中文翻译：

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组织学肺癌发病率和趋势因种族/民族和居住县而异

简介：在美国，非西班牙裔 (NH) 黑人的肺癌发病率高于 NH 白人和西班牙裔人群。然而，全国癌症估计并不总是反映小地理区域的差异和发病率方面的癌症负担，尤其是城乡差异。此外，关于癌症组织学类型方面城乡差异的文献存在空白。方法：使用基于人群的癌症登记数据——监测、流行病学和最终结果以及国家癌症登记计划数据——我们在首次癌症诊断时按种族/民族和居住县位置呈现年龄调整的组织学比率和趋势。计算比率以检查比率的种族/族裔差异。计算年度百分比变化以衡量速率随时间的变化。结果：我们发现鳞状细胞癌的下降在大城市县发生最快，而腺癌发病率在与大都市区不相邻的县增长最快。此外，尽管与所有地理位置的 NH 白人和西班牙裔男性相比，NH 黑人男性的肺癌发病率有所增加，但我们发现差异程度随着居住农村地区的增加而增加。最后，我们发现在 55 岁以下被诊断出肺癌的女性中，NH 黑人的鳞状细胞癌和腺癌的发病率高于 NH 白人。结论：我们的结果突出了非相邻农村地区 NH 黑人之间的差异。