SELDI-TOF MS Whole Serum Proteomic Profiling with IMAC Surface Does Not Reliably Detect Prostate Cancer (Proteomics and Protein Markers) (Clinical Report‪)‬

Each year prostatic adenocarcinoma is diagnosed in almost 220 000 men and is responsible for about 27 000 deaths, making it the 2nd leading cause of cancer death in men in the US (1). Because prostate cancer diagnosed while still localized to the prostate can be cured by a number of local therapies, early detection of this disease is a commonly practiced clinical strategy. Screening for increased concentrations of prostate-specific antigen [(PSA).sup.10] in serum is currently the most valuable approach for early detection of prostate cancer. Several large studies have reported that PSA alone is superior to digital rectal examination (DRE) and that PSA combined with DRE is the most effective early detection approach for prostate cancer (2-6). Widespread PSA screening programs have been associated with significant reduction in tumor stage at diagnosis and decreased numbers of cases diagnosed with metastases or poorly differentiated disease (7-9). Although the positive predictive value (PPV) of PSA has been reported as 80% for men with PSA concentrations 20 [micro]g/L, the PPV may be as low as 15% in men with serum PSA concentrations 4 [micro]g/L. Unfortunately, if diagnosed when PSA concentrations exceed 10 [micro]g/L, many men will have advanced disease (5, 7). Because PSA is prostate specific rather than prostate cancer specific, increased concentrations of PSA are found in benign prostatic hyperplasia (BPH) (10), acute and chronic prostatitis, prostatic ischemia/infarction, and prostatic intraepithelial neoplasia (PIN) (11). The Prostate Cancer Prevention Trial (PCPT) and other studies suggest that 15% of men will have prostate cancer even when their PSA is 4 [micro]g/L (2, 1214); however, dropping the cutoff value for PSA below 4 [micro]g/L may substantially increase the false-positive rate (11). Thus, there is a need for additional sensitive and specific screening tests for the early detection of prostate cancer.