Understand how prostate-specific antigen (PSA) is used in the monitoring of prostate cancer, and controversies regarding use of PSA as a cancer screening test.
Learn how β-human chorionic gonadotropin (β-hCG), alpha-fetoprotein (AFP), and lactate dehydrogenase (LD) levels are used in the management of patients with certain germ cell testicular tumors.
Learn the potential and limitations of bladder cancer urine markers.
Learn how tests of androgen metabolism and regulation can be used in diagnosis of male gonadal dysfunction.
Learn the major causes of male infertility, and the major tests involved in semen analysis.
Learn some of the issues involved in laboratory testing of transgender individuals.
The penis, testes, epididymis, vas deferens, seminal vesicles, and the prostate comprise the male genital tract, and disorders of the urethra and urinary bladder also are a consideration in patients presenting with genital tract symptoms. Circulating markers have been identified for prostate cancer and testicular cancer, and urine biomarkers have been proposed for bladder cancers. A discussion of these tumors and their serum and urine markers is presented in this chapter. Also, laboratory tests are often used in evaluating men with gonadal dysfunction and men who may be subfertile, infertile, or sterile. A summary of these tests and their usage is also provided. The male genital tract is the site of many infectious diseases, a significant proportion of which are sexually transmitted. These are discussed in Chapter 5.
Development of new tumor markers is an active area of research, in part because of ongoing clinical need, and in part because of scientific and technological changes that allow measurement of new biomarkers. Tumor markers most used in clinical practice have consisted of proteins (including glycoproteins) and hormones measured by various immunoassays. Results from measurement of more than one analyte can be combined using various algorithms and formulas to improve clinical associations and predictions. Emerging technologies and basic scientific advancements have led to assays for nucleic acids, including mutated DNA; DNA methylation and other epigenetic changes in DNA associated with malignancy; messenger RNAs that are enriched in tumors; and microRNAs (either free or associated with vesicles) associated with malignancy. Improvement in tumor marker assays has the potential to improve screening, diagnosis, prognostication, treatment selection, and monitoring of malignancy.
TABLE 19–1Clinical Utility of Serum Tumor Markers for Prostate Cancer and Testicular Cancer |Favorite Table|Download (.pdf) TABLE 19–1 Clinical Utility of Serum Tumor Markers for Prostate Cancer and Testicular Cancer
|Cancer Purpose ||Prostate Cancer: Prostate-specific Antigen (PSA) ||Testicular Germ Cell Tumors (LD, AFP, hCG) |
|Screening ||Controversial for men older than 50 years ||Not useful |
|Establishing a diagnosis ||Not useful ||Can suggest histologic type(s) present, especially for small clusters of one tumor type that may be missed by ...|