Ribeiro Karina Braga, Degar Barbara, Antoneli Célia Beatriz Gianotti, Rollins Barrett, Rodriguez-Galindo Carlos
Faculdade de Ciências Médicas da Santa Casa de São Paulo, Department of Social Medicine, São Paulo, Brazil.
Pediatr Blood Cancer. 2015 Jun;62(6):982-7. doi: 10.1002/pbc.25404. Epub 2015 Jan 13.
Langerhans cell histiocytosis (LCH) is a rare disease, and its etiology is not well understood. Population-based studies may contribute to etiologic research by defining incidence patterns. This study was designed to evaluate the descriptive epidemiology of disseminated LCH in the United States, using data from population-based cancer registries.
We analyzed the incidence and survival of disseminated LCH in children and adolescents (0-19 years) from 18 SEER registries during 2000-2009. Age-standardized incidence rates (ASIR) per million and rate ratios (RR) were calculated by gender, race, ethnicity, age, and socioeconomic variables (crowding, rural/urban, education, and poverty) using the SEER*Stat software 8.0.1. Relative survival (RS) estimates were calculated using Ederer II method.
One hundred forty-five cases of disseminated LCH were recorded; ASIR was 0.70/million per year. Lower ASIR was observed for blacks (vs. whites) (RR = 0.41, 95% CI 0.18-0.81), while higher ASIR was noted for Hispanics (vs. non-Hispanics) (RR = 1.63, 95% CI 1.15-2.29). Risk of LCH was higher in crowded counties (RR = 1.84, 95% CI 1.31-2.58) and also in areas with low educational level (RR = 1.49, 95% CI 1.02-2.22). Five-year relative survival was 90.0% (95% CI 83.0-94.2). Important differences in survival were noted according to gender (male: RS = 96.0 vs. female: RS = 83.4%, P = 0.029) and age (<1 year: RS = 78.5, 1-4 years: RS = 95.6%, 5-19 years: RS = 100%, P = 0.004).
This population-based study shows significant variations in the incidence of disseminated LCH by race and ethnic group, as well as the influence of socioeconomic factors. These data may provide clues to causation and point toward the need for analytical epidemiologic studies.
朗格汉斯细胞组织细胞增多症（LCH）是一种罕见疾病，其病因尚不完全清楚。基于人群的研究可能通过确定发病率模式有助于病因学研究。本研究旨在利用基于人群的癌症登记数据评估美国播散性LCH的描述性流行病学。
我们分析了2000 - 2009年期间18个监测、流行病学与最终结果（SEER）登记处中儿童和青少年（0 - 19岁）播散性LCH的发病率和生存率。使用SEER*Stat软件8.0.1按性别、种族、族裔、年龄和社会经济变量（拥挤程度、农村/城市、教育程度和贫困状况）计算每百万人口的年龄标准化发病率（ASIR）和率比（RR）。采用埃德勒二世方法计算相对生存率（RS）估计值。
记录了145例播散性LCH病例；ASIR为每年0.70/百万。黑人（与白人相比）的ASIR较低（RR = 0.41，95%可信区间0.18 - 0.81），而西班牙裔（与非西班牙裔相比）的ASIR较高（RR = 1.63，95%可信区间1.15 - 2.29）。LCH风险在人口拥挤的县较高（RR = 1.84，95%可信区间1.31 - 2.58），在教育水平低的地区也较高（RR = 1.49，95%可信区间1.02 - 2.22）。五年相对生存率为90.0%（95%可信区间83.0 - 94.2）。根据性别（男性：RS = 96.0对女性：RS = 83.4%，P = 0.029）和年龄（<1岁：RS = 78.5，1 - 4岁：RS = 95.6%，5 - 19岁：RS = 100%，P = 0.004）观察到生存率存在重要差异。
这项基于人群的研究表明，播散性LCH的发病率在种族和族裔群体中存在显著差异，以及社会经济因素的影响。这些数据可能为病因提供线索，并表明需要进行分析性流行病学研究。
