Alexander Dominik, Jhala Nirag, Chatla Chakrapani, Steinhauer Jon, Funkhouser Ellen, Coffey Christopher S, Grizzle William E, Manne Upender
Department of Epidemiology, University of Alabama-Birmingham, Birmingham, Alabama 35294-7331, USA.
Cancer. 2005 May 15;103(10):2163-70. doi: 10.1002/cncr.21021.
To identify the factors that contribute to poorer colon carcinoma survival rates for African Americans compared with Caucasians, the authors evaluated survival differences based on the histologic grade (differentiation) of the tumor.
All 169 African Americans and 229 randomly selected non-Hispanic Caucasians who underwent surgery during 1981-1993 for first primary sporadic colon carcinoma at the University of Alabama at Birmingham or its affiliated Veterans Affairs hospital were included in the current study. None of these patients received presurgery or postsurgery therapies. Recently, the authors reported an increased risk of colon carcinoma death for African Americans in this patient population, after adjustment for stage and other clinicodemographic features. The authors generated Kaplan-Meier survival probabilities according to race and tumor differentiation and multivariate Cox proportional hazards models to estimate hazard ratios (HR) with 95% confidence intervals (95% CI).
There were no differences in the distribution of pathologic tumor stage between racial groups after stratifying by histologic tumor grade. Among patients with high-grade tumors, 54% of African Americans and 21% of Caucasians died within the first year after surgery (P = 0.007). African Americans with high-grade tumors were 3 times (HR = 3.05; 95% CI, 1.32-7.05) more likely to die of colon carcinoma within 5 years postsurgery, compared with Caucasians with high-grade tumors. There were no survival differences by race among patients with low-grade tumors.
These findings suggested that poorer survival among African-American patients with adenocarcinomas of the colon may not be attributable to an advanced pathologic stage of disease at diagnosis, but instead may be due to aggressive biologic features like high tumor grades.
为了确定与白种人相比，导致非裔美国人结肠癌生存率较低的因素，作者基于肿瘤的组织学分级（分化程度）评估了生存差异。
本研究纳入了1981年至1993年间在阿拉巴马大学伯明翰分校或其附属退伍军人事务医院接受手术治疗的首例原发性散发性结肠癌的所有169名非裔美国人和229名随机选取的非西班牙裔白种人。这些患者均未接受术前或术后治疗。最近，作者报道了在对分期和其他临床人口统计学特征进行调整后，该患者群体中非裔美国人结肠癌死亡风险增加。作者根据种族和肿瘤分化情况生成了Kaplan-Meier生存概率，并使用多变量Cox比例风险模型来估计风险比（HR）及95%置信区间（95%CI）。
按组织学肿瘤分级分层后，种族群体之间的病理肿瘤分期分布没有差异。在高级别肿瘤患者中，54%的非裔美国人和21%的白种人在术后第一年内死亡（P = 0.007）。与高级别肿瘤的白种人相比，高级别肿瘤的非裔美国人术后5年内死于结肠癌的可能性高3倍（HR = 3.05；95%CI，1.32 - 7.05）。低级别肿瘤患者中，不同种族的生存率没有差异。
这些发现表明，非裔美国结肠癌腺癌患者生存率较低可能并非归因于诊断时疾病的晚期病理分期，而是可能由于高肿瘤分级等侵袭性生物学特征。
