Eastham James A, Riedel Elyn, Latkany Lianne, Fleisher Martin, Schatzkin Arthur, Lanza Elaine, Shike Moshe
Department of Urology, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
Urology. 2003 Oct;62(4):677-82. doi: 10.1016/s0090-4295(03)00576-4.
To examine whether a diet low in fat and high in fiber, fruits, and vegetables and ethnicity had any influence on serum prostate-specific antigen (PSA) levels, because serum PSA is a marker for the presence of prostate cancer. The incidence of prostate cancer increases with age, varies by ethnicity, and is greater among men with a first-degree relative who has had the disease. Large international variations in the rates of prostate cancer incidence and mortality, as well as the incidence changes in migrants and their offspring, also suggest that exogenous factors, including diet, have a strong influence on the development of this disease.
We used data and blood samples from the Polyp Prevention Trial, a multicenter randomized trial designed to evaluate the impact of a diet low in fat and high in fiber, fruits, and vegetables on the recurrence of colorectal adenomas. Recruitment was from 1991 through 1994. Participants were followed up from their baseline recruitment date for 4 years. From this group, we identified 1100 white men and 97 black men who were 35 years of age or older, did not have prostate cancer, and had serum samples available for study.
At baseline, no difference was present in the fat intake for the black and white men (mean +/- SE, 90 +/- 3.6 g/day and 84 +/- 1.0 g/day, respectively; P = 0.15). The baseline serum PSA levels did not vary by ethnicity. For black men, the mean serum PSA level was 2.2 +/- 0.36 ng/mL compared with 2.0 +/- 0.07 ng/mL for white men (P = 0.64). Although all men assigned to the intervention group markedly reduced their fat intake by approximately 15% and increased their fruit and vegetable intake by approximately 2.25 servings per day, no difference was noted in the kinetics of the serum PSA levels by dietary intervention or race.
Although ethnic differences in the incidence of prostate cancer are well defined, we found no difference in the baseline fat intake among black and white men that might have contributed to this difference. Serum PSA, a marker often used in early detection programs for prostate cancer, was not associated with manipulation of the amount of fat in the diet, regardless of ethnicity.
鉴于血清前列腺特异性抗原（PSA）是前列腺癌存在的一个标志物，研究低脂肪、高纤维、富含水果和蔬菜的饮食以及种族是否对血清PSA水平有任何影响。前列腺癌的发病率随年龄增长而增加，因种族而异，在有患该病的一级亲属的男性中更高。前列腺癌发病率和死亡率在国际上存在很大差异，以及移民及其后代的发病率变化，也表明包括饮食在内的外部因素对这种疾病的发展有很大影响。
我们使用了息肉预防试验的数据和血样，这是一项多中心随机试验，旨在评估低脂肪、高纤维、富含水果和蔬菜的饮食对结直肠腺瘤复发的影响。招募时间为1991年至1994年。参与者从基线招募日期开始随访4年。从这个群体中，我们确定了1100名35岁及以上、没有前列腺癌且有血清样本可供研究的白人男性和97名黑人男性。
在基线时，黑人和白人男性的脂肪摄入量没有差异（平均±标准误，分别为90±3.6克/天和84±1.0克/天；P = 0.15）。基线血清PSA水平不因种族而异。黑人男性的平均血清PSA水平为2.2±0.36纳克/毫升，而白人男性为2.0±0.07纳克/毫升（P = 0.64）。尽管所有被分配到干预组的男性明显将其脂肪摄入量减少了约15%，并将其水果和蔬菜摄入量增加了约每天2.25份，但通过饮食干预或种族在血清PSA水平的变化趋势上未发现差异。
尽管前列腺癌发病率的种族差异已明确，但我们发现黑人和白人男性的基线脂肪摄入量没有差异，而这种差异可能导致了前列腺癌发病率的不同。血清PSA是前列腺癌早期检测项目中常用的一个标志物，无论种族如何，它与饮食中脂肪量的改变均无关联。
