Disparities in Kaposi sarcoma incidence and survival in the United States: 2000-2013

ObjectiveGeographic and racial disparities may contribute to variation in the incidence and outcomes of HIV-associated cancers in the United States.MethodUsing the Surveillance, Epidemiology, and End Results (SEER) database, we analyzed Kaposi sarcoma (KS) incidence and survival by race and geographic region during the combined antiretroviral therapy era. Reported cases of KS in men from 2000 to 2013 were obtained from 17 SEER cancer registries. Overall and age-standardized KS incidence rates were calculated and stratified by race and geographic region. We evaluated incidence trends using joinpoint analyses and calculated adjusted hazard ratios (aHR) for overall and KS-specific mortality using multivariable Cox proportional hazards models.ResultsOf 4,455 KS cases identified in men younger than 55 years (median age 40 years), the annual percent change (APC) for KS incidence significantly decreased for white men between 2001 and 2013 (APC -4.52, p = 0.02). The APC for AA men demonstrated a non-significant decrease from 2000–2013 (APC -1.84, p = 0.09). Among AA men in the South, however, APC has significantly increased between 2000 and 2013 (+3.0, p = 0.03). In addition, compared with white men diagnosed with KS during the same time period, AA men were also more likely to die from all causes and KS cancer-specific causes (aHR 1.52, 95% CI 1.34–1.72, aHR 1.49, 95% CI 1.30–1.72 respectively).ConclusionAlthough overall KS incidence has decreased in the U.S., geographic and racial disparities in KS incidence and survival exist.

研究目的：美国艾滋病相关癌症的发病率与临床转归或存在地理与种族差异。
研究方法：本研究依托监测、流行病学与最终结果（Surveillance, Epidemiology, and End Results, SEER）数据库，分析联合抗逆转录病毒治疗时代下不同种族与地理区域的卡波西肉瘤（Kaposi sarcoma, KS）发病率及生存情况。我们从17家SEER癌症登记处提取2000年至2013年的男性卡波西肉瘤报告病例，计算总体及年龄标化的卡波西肉瘤发病率，并按种族与地理区域进行分层分析。采用连接点回归分析评估发病率变化趋势，通过多变量Cox比例风险模型计算全因死亡与卡波西肉瘤特异性死亡的校正风险比（adjusted hazard ratios, aHR）。
研究结果：本研究共纳入4455例55岁以下的男性卡波西肉瘤病例，中位年龄为40岁。2001年至2013年间，白人男性的卡波西肉瘤发病率年变化率（annual percent change, APC）显著下降（APC=-4.52，p=0.02）；非裔美国男性（African American, AA）的发病率年变化率在2000年至2013年间呈不显著下降趋势（APC=-1.84，p=0.09）。但美国南部地区的非裔美国男性（African American, AA），其发病率年变化率在2000年至2013年间显著上升（APC=+3.0，p=0.03）。此外，与同期确诊卡波西肉瘤的白人男性相比，非裔美国男性（African American, AA）的全因死亡及卡波西肉瘤特异性死亡风险均显著升高，校正风险比分别为1.52（95%置信区间1.34~1.72）、1.49（95%置信区间1.30~1.72）。
研究结论：尽管美国整体卡波西肉瘤发病率呈下降趋势，但该病的发病率与生存结局仍存在地理与种族差异。