Whittemore Alice S, Cirillo Piera M, Feldman David, Cohn Barbara A
Department of Health Research and Policy, Stanford University School of Medicine, California 94305-5405, USA.
J Urol. 2005 Sep;174(3):872-6; discussion 876. doi: 10.1097/01.ju.0000169262.18000.8a.
Prostate specific antigen (PSA) is a serine protease produced by normal and malignant prostate epithelial cells. Serum PSA increases with age, due largely to age related increases in the prevalence of benign prostatic disease. Little is known about PSA distribution in young adulthood, when benign and malignant prostatic diseases are rare, or about how PSA within the normal range in youth relates to subsequent prostate cancer risk.
We evaluated serum PSA and subsequent prostate cancer occurrence in a cohort of young black and white American men with a median age at blood draw of 34 years, who in 1959 to 1966 participated as the fathers of newborns enrolled in the Child Health and Development Study, and who were followed for several decades for prostate cancer. We examined associations between PSA in young adulthood and subsequent prostate cancer risk using a nested case-control design based on 119 black and 206 white cases with 2 control men matched to each case on race and year of birth.
Prostate cancer risk increased with increasing PSA in black and white men. The OR comparing risk in the highest to lowest quartiles of PSA was 4.4 (95% CI 2.0 to 9.6) in black men and 3.5 (95% CI 2.0 to 6.1) in white men. ORs relating risk to PSA were higher when analysis was restricted to cases diagnosed before age 65 years.
These findings suggest that PSA levels in young adulthood indicate increased risk of prostate cancer and, thus, they may be useful for targeting men for screening and early diagnosis.
前列腺特异性抗原（PSA）是一种由正常和恶性前列腺上皮细胞产生的丝氨酸蛋白酶。血清PSA水平随年龄增长而升高，这在很大程度上归因于良性前列腺疾病患病率随年龄增加而上升。对于年轻成年期（此时良性和恶性前列腺疾病罕见）的PSA分布情况，以及青年时期处于正常范围内的PSA与后续前列腺癌风险之间的关系，我们知之甚少。
我们评估了一群美国黑人和白人年轻男性的血清PSA水平以及后续前列腺癌的发生情况。这些男性抽血时的中位年龄为34岁，他们在1959年至1966年期间作为参加儿童健康与发育研究的新生儿的父亲参与了研究，并对前列腺癌进行了数十年的随访。我们采用巢式病例对照设计，以119名黑人病例和206名白人病例为基础，每例病例匹配2名在种族和出生年份上与之匹配的对照男性，研究青年成年期的PSA与后续前列腺癌风险之间的关联。
黑人和白人男性中，前列腺癌风险均随PSA水平升高而增加。PSA最高四分位数与最低四分位数相比，黑人男性的OR为4.4（95%CI 2.0至9.6），白人男性为3.5（95%CI 2.0至6.1）。当分析仅限于65岁之前确诊的病例时，风险与PSA的OR更高。
这些发现表明，青年成年期的PSA水平表明前列腺癌风险增加，因此，它们可能有助于确定需要进行筛查和早期诊断的男性对象。
