The authors address the issue of cancer detected by chance. This phenomenon, termed serendipity, occurs when a screening test (ie, digital rectal examination or prostate-specific antigen) is abnormal due to benign conditions and cancer is coincidentally detected. The authors caution us regarding the uncertainties regarding prognosis and impact of aggressive treatment on the natural history of prostate cancer. They conclude that the best approach for the early detection of prostate cancer has yet to be defined.

    Benoit RM, Naslund MJ. The economics of prostate cancer screening. Oncology (Huntingt). 1997;11:1533-1543.

    Concerns over the increased health care costs associated with widespread screening are addressed. The authors discuss models to calculate costs from screening and the impact of stage migration on these costs. They estimate that screening for prostate cancer is more cost effective than screening for cervical and breast cancer. The analysis presented in this paper suggests that screening and the consequent early treatment of prostate cancer may be cost effective.

    Carlson GD, Calvanese CB, Partin AW. An algorithm combining age, total prostate-specific antigen (PSA), and percent free PSA to predict prostate cancer: results on 4298 cases. Urology. 1998;52:455-461.

    Various means to improve the performance of PSA have been proposed. These include PSA density, PSA velocity, age-adjusted PSA, and percent-free PSA. The authors propose a model that combines age, total PSA, and percent-free PSA. In their study, this model had increased sensitivity and specificity.

    Fair WR, Fleshner NE, Heston W. Cancer of the prostate: a nutritional disease? Urology. 1997; 50: 840-848.

    The impact of nutrition in the promotion or prevention of prostate cancer has been evaluated for decades. Fat and soy intake, different vitamins, and the trace metal selenium have been previously studied. In this comprehensive review, the authors discuss the current knowledge regarding these nutritional agents.

    Dalu A, Haskell JF, Coward L, et al. Genistein, a component of soy, inhibits the expression of the EGF and ErbB2/Neu receptors in the rat dorsolateral prostate. Prostate. 1998;37:36-43.

    Asian men have a low incidence of prostate cancer. Asian diet is rich in soy. The phytoestrogen genistein, a component of soy, has been implicated as the reason for this decreased incidence. The authors demonstrate that genistein inhibits tyrosine-phosphorylated proteins in a rat model. They conclude that genistein downregulates the EGF and ErbB2/Neu receptors in the rat prostate and that it may be useful in both protecting against and treating prostate cancer.

    Bova GS, Partin AW, Isaacs SD, et al. Biological aggressiveness of hereditary prostate cancer: long-term evaluation following radical prostatectomy. J Urol. 1998;160: 660-663.

    Familial prostate cancer has been stratified recently in two types: men with a family history of prostate cancer and the hereditary prostate cancer syndrome (HPC). The former defines men with prostate cancer who have a father or at least one brother with prostate cancer. HPC is defined as a family with three generations affected, three first-degree relatives affected, or two relatives affected before age 55. The investigators compare the rate of PSA progression between men with and without a family history of prostate cancer and men with or without HPC who underwent radical prostatectomy. There was no statistically significant difference in the probability of maintaining an undetectable PSA among the groups. They conclude that there is no biologically important difference between hereditary and sporadic prostate cancers.

    Kallakury BV, Sheehan CE, Ambros RA, et al. Correlation of p34cdc2 cyclin-dependent kinase overexpression, CD44s downregulation, and HER-2/neu oncogene amplification with recurrence in prostatic adenocarcinomas. J Clin Oncol. 1998;16:1302-1309.

    As a product of the cell division control gene, p34cdc2 cyclin-dependent kinase (CDK) plays a role in the control of mammalian somatic cell-cycle progression. CD44s, a transmembrane glycoprotein, plays an important role in various cell-cell and cell-matrix interactions. The HER-2/neu oncogene encodes a transmembrane glycoprotein member of the epidermal growth-factor-receptor subgroup of the tyrosine kinase superfamily. The investigators demonstrate that these proteins and oncogene are variably expressed or amplified in prostate cancer and that such alterations may affect tumor behavior. They suggest that CDK overexpression and HER-2/neu amplification may be biologically related.

    Hedlund TE, Duke RC, Schleicher MS, et al. Fas-mediated apoptosis in seven human prostate cancer cell lines: correlation with tumor stage. Prostate. 1998;36:92-101.

    Fas, a member of the tumor necrosis factor receptor superfamily, is a cell surface receptor capable of initiating an apoptotic signaling pathway when bound to its ligand. This recent study supports previous studies suggesting that the normal, differentiated prostatic epithelium, as well as locally invasive prostate cancer, has the potential to undergo fas-mediated apoptosis. Metastatic prostate cancer have a reduced potential for apoptosis.

    D’Amico A, Whittington R, Malkowicz B, et al. Biochemical outcomes after radical prostatectomy, external beam radiation therapy, or interstitial radiation therapy for clinically localized prostate cancer. JAMA. 1998;280:969-974.

    Prostate-specific antigen (PSA) control after three treatment modalities for clinically localized prostate cancer was estimated. Patients were stratified in low-risk, intermediate-risk, and high-risk groups. Low-risk patients had similar five-year PSA outcomes regardless of treatment. Intermediate- and high-risk patients had a worst outcome when treated with brachytherapy. The reader is cautioned that this observation is currently well known and that contemporarily, patients with poor-risk cancers are not treated with brachytherapy alone but with a combination of preemptive hormonal therapy, external beam radiation therapy, and brachytherapy.

    The Medical Research Council Prostate Cancer Working Party Investigators Group. Immediate versus deferred treatment for advanced prostatic cancer: initial results of the Medical Research Council Trial. Br J Urol. 1997;79: 235-246.

    Hormonal therapy has been the mainstay for the treatment of advanced prostate cancer for over five decades. The optimal timing for instituting treatment in advanced disease is still controversial. In this randomized study of early vs deferred treatment, the investigators observed better local control and delayed progression in patients treated immediately.

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