Bowerman R J
Department of Health and Social Services, Barrow, Alaska 99723, USA.
Public Health. 1998 Jan;112(1):7-13. doi: 10.1016/s0033-3506(98)00199-1.
Cancer incidence and its possible relation to environmental contaminants, including radiation, continues to be a perceived health threat for the arctic-dwelling Alaska Native (Inupiat Eskimo) people despite the lack of a direct link to high-dose exposure. To better understand this concern, all known malignancies diagnosed in this population (n = 177) in three consecutive eight-year periods (1971-1994) were evaluated. The most recent average incidence rate (age-adjusted to world standard population) of 315 per 100,000 (95% confidence interval, CI = 248-382) represents a 33% surge (albeit non-significant) in Alaska Native cancer incidence over the initial period studied. The male rate 366 (95% CI = 266-466) for the same period exceeds the female rate 258 (95% CI = 169-347) by 42%. Two patterns of cancer incidence are seen at the village level. One, a 24 y upward trend found in the villages of Barrow, Point Hope and Kaktovik (combined rate of increase significant [P = 0.047]) associated with lung cancer; and the other, a stable trend over the past 16 y, associated with colon and rectal cancer. Lung cancer is the predominant cancer by site and is primarily a male disease. The recent male lung cancer incidence rate of 137 (95% CI = 73-201) exceeds the female rate by greater than five times. Total lung cancer cases are primarily confined to four villages where the incidence significantly (P = 0.0043) exceeds the remaining population. The major female cancers are colon/rectal and breast with cancer of the cervix virtually eliminated. Breast cancer is found primarily in two villages where its excess is significant (P = 0.025). Inupiat Eskimo cancer epidemiology is unique, differing from both the Alaska Native and other Circumpolar populations. At present, this uniqueness cannot be explained by an overt environmental contaminant exposure. Although tobacco very likely plays a central role, it by itself cannot fully explain the extremely high male lung cancer rate and why only specific villages are affected. Genetic predisposition and environmental factors may play a synergistic role as cofactors. A cooperative investigative effort with the Inupiat population is indicated and may go a long way in reducing cancer concern in the region.
尽管缺乏与高剂量暴露的直接联系，但癌症发病率及其与包括辐射在内的环境污染物的可能关系，仍然被认为是对居住在北极地区的阿拉斯加原住民（因纽皮特爱斯基摩人）的健康威胁。为了更好地理解这一问题，对该人群在连续三个八年期间（1971 - 1994年）诊断出的所有已知恶性肿瘤（n = 177）进行了评估。最近的平均发病率（年龄调整至世界标准人口）为每10万人315例（95%置信区间，CI = 248 - 382），表明阿拉斯加原住民癌症发病率在研究初期基础上激增了33%（尽管不显著）。同期男性发病率为366（95%CI = 266 - 466），比女性发病率258（95%CI = 169 - 347）高出42%。在村庄层面可见两种癌症发病模式。一种是在巴罗、希望角和卡克托维克村发现的24年上升趋势（合并增长率显著[P = 0.047]），与肺癌相关；另一种是过去16年的稳定趋势，与结肠癌和直肠癌相关。肺癌是主要的癌症类型，且主要是男性疾病。近期男性肺癌发病率为137（95%CI = 73 - 201），超过女性发病率五倍多。肺癌病例主要集中在四个村庄，其发病率显著（P = 0.0043）高于其他人群。女性主要的癌症是结肠癌/直肠癌和乳腺癌，宫颈癌几乎消失。乳腺癌主要在两个村庄发现，其发病率过高具有显著性（P = 0.025）。因纽皮特爱斯基摩人的癌症流行病学是独特的，既不同于阿拉斯加原住民，也不同于其他环北极人群。目前，这种独特性无法用明显的环境污染物暴露来解释。尽管烟草很可能起核心作用，但它本身无法完全解释男性极高的肺癌发病率以及为何只有特定村庄受到影响。遗传易感性和环境因素可能作为辅助因素发挥协同作用。需要与因纽皮特人群开展合作调查，这可能在很大程度上减少该地区对癌症的担忧。
