1 Alaska Native Tumor Registry, Alaska Native Epidemiology Center , Community Health Services, Alaska Native Tribal Health Consortium, Anchorage, Alaska.
2 Department of Internal Medicine, Alaska Native Medical Center , Anchorage, Alaska.
Thyroid. 2018 Apr;28(4):481-487. doi: 10.1089/thy.2017.0408. Epub 2018 Mar 19.
Nationwide, the incidence of thyroid cancer is lower among American Indian/Alaska Native (AI/AN) people than among U.S. whites (USW). However, little is known about the incidence of thyroid or other endocrine cancers specifically among Alaska Native (AN) people.
Data were examined from the National Cancer Institute's Surveillance, Epidemiology, and End Results Alaska Native Tumor Registry on endocrine cancers diagnosed among AN people from 1969-2013, with a specific focus on thyroid cancers. Frequencies of endocrine cancers by site and also of thyroid cancers by histology, size, and stage at diagnosis were evaluated. Distributions were compared to USW (Surveillance, Epidemiology, and End Results 9 Registries) using the chi-square test. Five-year average annual age-adjusted incidence rates of thyroid cancers were calculated, stratified by histology, age, and five-year period of diagnosis, and compared to those observed among USW. Five-year cause-specific survival was evaluated using cause of death data from the National Death Index Plus from the National Center for Health Statistics.
During the 45-year period (1969-2013), 224 endocrine cancers were diagnosed among AN people, of which 210 (94%) were thyroid cancers. Compared to USW, AN people were diagnosed at a slightly younger age, had a higher proportion of thyroid cancers diagnosed with a size of 20-40 mm, and a larger proportion of patients with regional metastases. More than 85% of AN thyroid cancers were of papillary histology. The incidence of thyroid cancers was similar between AN people and USW, and appeared to increase among AN people over the period of surveillance. Finally, five-year cause-specific survival rate was 100% for papillary carcinoma patients and 86.3% [confidence interval 54.7-96.5] for follicular thyroid cancer patients.
This study is the first report of endocrine cancers and the first detailed examination of thyroid cancer among AN people. The incidence of thyroid cancer was similar among AN people and USW. However, compared to USW, AN people appear to be at risk for diagnosis at a younger age, larger size, and higher stage. Further research is needed to explore the causes of these differences.
全美范围内，印第安/阿拉斯加原住民（AI/AN）人群的甲状腺癌发病率低于美国白人（USW）。然而，关于阿拉斯加原住民（AN）人群中甲状腺癌或其他内分泌癌的发病率知之甚少。
本研究利用美国国家癌症研究所监测、流行病学和最终结果阿拉斯加原住民肿瘤登记处的数据，对 1969 年至 2013 年间诊断的 AN 人群中的内分泌癌进行了研究，特别关注甲状腺癌。评估了不同部位的内分泌癌发病率，以及不同组织学类型、大小和诊断时分期的甲状腺癌发病率。使用卡方检验比较了 AN 人群与 USW（监测、流行病学和最终结果 9 个登记处）的分布情况。根据组织学类型、年龄和诊断五年期，计算了不同年龄组和五年期的甲状腺癌五年平均年龄调整发病率，并与 USW 进行了比较。利用国家卫生统计中心国家死亡指数加的死亡原因数据评估了五年特异性生存率。
在 45 年的研究期间（1969 年至 2013 年），共诊断出 224 例内分泌癌，其中 210 例（94%）为甲状腺癌。与 USW 相比，AN 人群的诊断年龄稍小，诊断为 20-40mm 大小的甲状腺癌比例较高，区域转移的患者比例较大。超过 85%的 AN 甲状腺癌为乳头状组织学类型。AN 人群和 USW 的甲状腺癌发病率相似，并且在监测期间似乎有所增加。最后，乳头状癌患者的五年特异性生存率为 100%，滤泡状甲状腺癌患者为 86.3%[置信区间 54.7-96.5]。
本研究首次报道了 AN 人群中的内分泌癌，并首次详细研究了 AN 人群中的甲状腺癌。AN 人群的甲状腺癌发病率与 USW 相似。然而，与 USW 相比，AN 人群的诊断年龄较小，肿瘤较大，分期较高。需要进一步研究以探讨这些差异的原因。
