Vijayakumar S, Karrison T, Weichselbaum R R, Chan S, Quadri S F, Awan A M
Michael Reese/University of Chicago Center for Radiation Therapy 60616.
Cancer Epidemiol Biomarkers Prev. 1992 Nov-Dec;1(7):541-5.
Prostate cancer is a significant health problem for blacks. The incidence and mortality rates are higher in blacks than in whites; blacks often present with a higher stage. Prostate-specific antigen (PSA) is a very useful serum marker in prostate cancer. We analyzed data from a cohort of 161 patients to determine whether there were any racial differences in PSA levels prior to treatment in local-regional prostate cancer. The immunoradiometric method was used to determine the PSA values. The mean PSA levels were significantly higher in blacks than in whites (P = 0.022), and the difference remained significant in multivariate analysis after adjusting for stage and grade (P = 0.020). However, when analyzed further, the difference was statistically significant in one hospital (P = 0.001) and not in another (P = 0.493). Thus, our results are not unequivocal, but our data do suggest that racial differences in PSA levels not accounted for by tumor stage or grade may exist. Assuming that the data truly reflect a racial difference, the cause(s) of this difference remains to be determined. It may exist because, within each clinical stage, blacks are presenting with a higher tumor cell burden, or it may be indicative of more aggressive biological behavior. The possibility that racial differences are due to socioeconomic factors was considered by estimating median income level from zip code of residence; although a correlation between socioeconomic status and PSA level was found, racial differences remained borderline significant (P = 0.055) after adjusting for income level (in addition to stage and grade).
前列腺癌是黑人面临的一个重大健康问题。黑人的发病率和死亡率高于白人；黑人通常就诊时分期较高。前列腺特异性抗原（PSA）是前列腺癌中一种非常有用的血清标志物。我们分析了161例患者队列的数据，以确定局部区域前列腺癌患者治疗前PSA水平是否存在种族差异。采用免疫放射分析法测定PSA值。黑人的平均PSA水平显著高于白人（P = 0.022），在调整分期和分级后进行多变量分析时，差异仍然显著（P = 0.020）。然而，进一步分析时，在一家医院差异具有统计学意义（P = 0.001），而在另一家医院则无统计学意义（P = 0.493）。因此，我们的结果并不明确，但我们的数据确实表明，可能存在未被肿瘤分期或分级所解释的PSA水平种族差异。假设这些数据真实反映了种族差异，这种差异的原因仍有待确定。可能是因为在每个临床分期内，黑人的肿瘤细胞负荷更高，或者这可能表明其生物学行为更具侵袭性。通过根据居住邮政编码估算收入中位数水平，考虑了种族差异是否由社会经济因素导致；尽管发现社会经济地位与PSA水平之间存在相关性，但在调整收入水平（以及分期和分级）后，种族差异仍接近显著水平（P = 0.055）。
