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A correction to the article "Frequent overexpression of ETS-related gene-1 (ERG1) in prostate cancer transcriptome" that was previously published in "Oncogene" is presented.

Background: The detection of prostate cancer by screening for prostate-specific antigen (PSA) in serum is improved when age-specific reference ranges are used, but these ranges have been derived from white populations. We determined the distribution of PSA and age-specific reference ranges in black men both with and without prostate cancer. Methods: From January 1991 through May 1995, we measured serum PSA in 3475 men with no clinical evidence of prostate cancer (1802 white and 1673 black) and 1783 men with prostate cancer (1372 white and 411 black). We studied the data as a function of age and race to determine the usefulness of measuring PSA in diagnosing prostate cancer. Results: Serum PSA concentrations in black men (geometric mean in controls, 1.48 ng per milliliter; in patients, 7.46) were significantly higher than those in white men (geometric mean in controls, 1.33 ng per milliliter; in patients, 6.28). The values in the controls correlated directly with age. The area under the receiver-operating-characteristic curve was 0.91 for blacks and 0.94 for whites. If traditional age-specific reference ranges were used in screening black men, with the test specificity kept at 95 percent, 41 percent of cases of prostate cancer would be missed. For the test to have 95 percent sensitivity among black men, the following normal reference ranges should be used: for men in their 40s, 0 to 2.0 ng of PSA per milliliter (test specificity, 93 percent); for men in their 50s, 0 to 4.0 ng per milliliter (specificity, 88 percent); for men in their 60s, 0 to 4.5 ng per milliliter (specificity, 81 percent); and for men in their 70s, 0 to 5.5 ng per milliliter (specificity, 78 percent). Conclusions: Serum PSA concentrations can be used to discriminate between men with prostate cancer and those without it among both blacks and whites. Over 40 percent of cases of prostate cancer in black men would not be detected by tests using traditional age-specific reference ranges, which maintain specificity at 95 percent. In this high-risk population, the alternative approach — maintaining sensitivity at 95 percent — may be used with acceptable decrements in specificity. (N Engl J Med 1996;335:304-10.) [ABSTRACT FROM AUTHOR]

Research into molecular and genetic mechanisms underlying prostate carcinogenesis would be greatly advanced by in vitro models of prostate tumors representing primary tumors. We have successfully established an immortalized human prostate epithelial (HPE) cell culture derived from a primary tumor with telomerase. The actively proliferating early passaged RC-58T cells were transduced through infection with a retrovirus vector expressing the human telomerase catalytic subunit (hTERT). A high level of telomerase was detected in RC-58T/hTERT cells but not RC-58T cells. RC-58T/hTERT cells are currently growing well at passage 50, whereas RC-58T cells senesced at passage 7. RC-58T/hTERT cells exhibit transformed morphology. More importantly, these immortalized cells showed anchorage-independent growth as they formed colonies in soft agar and grew above the agar layer. Expression of androgen-regulated prostate specific gene NKX3.1 and epithelial specific cytokeratin 8 (CK8) but not prostate specific antigen (PSA) and androgen receptor was detected in RC-58T/hTERT cells. Prostate stem cell antigen (PSCA) and p16 were also expressed in this cell line. RC-58T/hTERT cells showed growth inhibition when exposed to retinoic acid and transforming growth factor (TGF)-beta1 known potent inhibitors of prostate epithelial cell growth. A number of chromosome alterations were observed including the loss of chromosomes Y, 3p, 10p, 17p, 18q and the gain of chromosomes 16 and 20. These results demonstrate that this primary tumor-derived HPE cell line retained its transformed phenotypes and should allow studies to elucidate molecular and genetic alterations involved in prostate cancer. This is the first documented case of an established human prostate cancer cell line from a primary tumor of a prostate cancer patient with telomerase.

Quantitative expression profile of androgen-regulated genes (ARGs) was evaluated in the hormone-responsive prostate cancer cell line LNCaP by serial analysis of gene expression (SAGE). A total of 83,489 SAGE tags representing 23,448 known genes or expressed sequence tags (ESTs) and 1,655 potentially novel sequences have unraveled the transcriptome of LNCaP cells, the most common cell line used in prostate cancer research. Comparison of transcripts between control and R1881-treated LNCaP cells revealed the induction of 136 genes and repression of 215 genes in response to androgen (p < 0.05). Strikingly, a high fraction ( approximately 90%) of ARGs identified in our study has not been described as ARGs previously. A number of prostate-specific transcription factors were among the ARGs identified here. Classification of the ARGs on the basis of biochemical functions revealed that a great majority of ARGs identified in our experimental system appear to be involved in regulation of transcription, splicing, ribosomal biogenesis, mitogenesis, bioenergetics and redox processes. One of the novel aspects of androgen signaling included androgen regulation of genes involved in DNA repair/recombination process. By comparing our LNCaP-C and LNCaP-T SAGE libraries with SAGE tag libraries available at the NCBI-SAGE website, we have identified >200 potential prostate specific/abundant transcripts. The discovery of new prostate-specific genes and ARGs provides a unique opportunity to determine the role of these genes in prostate cell growth, differentiation and tumorigenesis., (Copyright 2001 Wiley-Liss, Inc.)

Objective: To review and compare the outcome of patients undergoing radical retropubic prostatectomy (RRP) or radical perineal prostatectomy (RPP) for clinically localized prostate cancer., Patients and Methods: From 1988 to 1997, 1382 men who were treated by RRP and 316 by RPP were identified from databases of the Uniformed Services Urology Research Group. The following variables were assessed; age, race, prostate-specific antigen (PSA) level before surgery, clinical stage, biopsy Gleason sum, estimated blood loss (EBL), margin-positive rate, pathological stage, biochemical recurrence rate, short and long-term complication rates, impotence and incontinence rates. To eliminate selection bias, the analysis was concentrated on pairs of patients matched by race, preoperative PSA level, clinical stage and biopsy Gleason sum., Results: In the 190 matched patients there were no significant differences between the RRP and RPP groups in either organ-confined (57% vs 55%), margin-positive (39% vs 43%), or biochemical recurrence rates (12.9% vs 17.6% at a mean follow-up of 47.1 vs 42.9 months), respectively. The mean EBL was 1575 mL in the RRP group and 802 mL in the RPP group (P < 0.001). The only significant difference in complication rates was a higher incidence of rectal injury in the RPP group (4.9%) than in the RRP group (none, P < 0.05)., Conclusions: In similar populations of patients, RPP offers equivalent organ-confined, margin-positive and biochemical recurrence rates to RRP, while causing significantly less blood loss.

Background: Over the past 5 years, a steady stream of publications has discussed the use of artificial neural networks (ANNs) for urologic and other medical applications. The pace of this research has increased recently, and deployed products based on this technology are now appearing. Before these tools can be widely accepted by clinicians and researchers, a deeper level of understanding of ANNs is necessary. This article attempts to lay some of the groundwork needed to facilitate this familiarity., Methods: A short discussion of neural network history is included for background. This is followed by an in-depth discussion of how and why ANNs work. This discussion includes the relationship between ANNs and statistical regression. An investigation of issues associated with neural networks follows, applicable to both general and urologic-specific applications., Results: Neural networks are computer models that have been studied extensively for over 50 years, with prostate cancer applications since 1994. From a biological viewpoint, ANNs are artificial analogues of data structures that exist in nervous systems. From a numeric viewpoint, ANNs are matrices of numbers whose values comprise knowledge that is distilled from historic databases. Many types of neural networks are analogous to well-known statistical methods., Conclusions: ANNs are complex numeric constructs, but no more complex than similar statistical methods. However, several issues associated with neural network derivation demand that developers apply rigorous engineering practices in their studies., (Copyright 2001 Wiley-Liss, Inc.)

PSGR, a new prostate tissue-specific gene with homology to the G protein-coupled odorant receptor gene family, has been identified. Here we report the characteristics of the predicted protein sequence of PSGR and its prostate tissue specificity and expression profile in human prostate cancer and matched normal tissues. Using multiple tissue Northern blots from over 50 different tissues, PSGR expression was restricted to human prostate tissues. Paired normal and tumor specimens from 52 primary prostate cancers, obtained by laser capture microdissection or manual microdissection, were analyzed for PSGR expression by semiquantitative and real-time PCR assays. The differential expression of PSGR between normal and tumor tissues was highly significant (P < 0.001), and 32 of 52 (62%) matched prostate specimens exhibited tumor-associated overexpression of PSGR. Of note, there was very little or no expression of PSGR in many normal specimens in comparison with the generally high expression of PSGR seen in matched tumor specimens. In situ hybridization assays showed restricted PSGR expression in the epithelial cells of the normal and tumor tissue sections. Restricted expression of PSGR in prostatic epithelial cells, overexpression of the PSGR in a significant percentage of prostate cancers, and the predicted protein sequence of PSGR with seven transmembrane domains provide a foundation for future studies evaluating the potential of PSGR as a prostate cancer gene expression marker and the utility of PSGR protein as a novel target for developing immunotherapeutic strategies for prostate cancer.

A prostate-specific gene, PCGEM1, was identified by differential display analysis of paired normal and prostate cancer tissues. Multiple tissue Northern blot analysis revealed that PCGEM1 was expressed exclusively in human prostate tissue. Analysis of PCGEM1 expression in matched normal and primary tumor specimens revealed tumor-associated overexpression in 84% of patients with prostate cancer by in situ hybridization assay and in 56% of patients by reverse transcription-PCR assay. Among various prostate cancer cell lines analyzed, PCGEM1 expression was detected only in the androgen receptor-positive cell line LNCaP. Extensive DNA sequence analysis of the PCGEM1 cDNA and genomic DNA revealed that PCGEM1 lacks protein-coding capacity and suggests that it may belong to an emerging class of noncoding RNAs, also called "riboregulators." The PCGEM1 locus was mapped to chromosome 2q32. Taken together, the remarkable prostate-tissue specificity and androgen-dependent expression of PCGEM1 as well as its elevated expression in a significant percentage of tumor tissues suggest specific functions of PCGEM1 in the biology and tumorigenesis of the prostate gland.

Purpose: We performed a randomized trial to compare the efficacy and toxicity of a new dose of flutamide (500 mg QD) with the currently recommended dose (250 mg q8h) in the treatment of advanced prostate cancer. The primary endpoints were percent of patients having normalization of prostate specific antigen (PSA), time to normalization, and percent change from baseline. Secondary endpoints were quality of life and toxicity., Patients: Altogether, 440 men aged 46 to 94 years (mean 71 years) with confirmed stage M(1) disease, documented PSA rise >0.2 ng/mL, ECOG status 0 to 2, no second neoplasm, no liver function tests > or = 1.5-fold normal values, and no previous treatment for metastatic disease were entered in the trial., Results: The PSA normalized by week 12 in 71% of the patients receiving 500-mg dose and 75% of those receiving the standard dose. The percent change in PSA was 89% and 96%, respectively. The treatment groups were not significantly different with respect to the incidence of adverse events: 71% v 68% in the 500-mg and 250-mg arms, respectively (P = 0.337)., Conclusions: When combined with castration, 500 mg of flutamide appears to be equally effective in lowering serum PSA and is not significantly more toxic than conventional dosing. The use of 500 mg QD instead of the standard 250 mg q8h would result in a cost savings of 30%.

Biologic effects of androgen on target cells are mediated in part by transcriptional regulation of androgen-regulated genes (ARGs) by androgen receptor. Using serial analysis of gene expression (SAGE), we have identified a comprehensive repertoire of ARGs in LNCaP cells. One of the SAGE-derived tags exhibiting homology to an expressed sequence tag was maximally induced in response to synthetic androgen R1881 treatment. The open reading frame of the androgen-induced RNA (PMEPA1) was characterized as a 759-bp nucleotide sequence coding for a 252-amino-acid protein. The analysis of PMEPA1 protein sequence indicated the existence of a type Ib transmembrane domain between residues 9 and 25. Analysis of multiple-tissue Northern blots revealed the highest level of PMEPA1 expression in prostate tissue. PMEPA1 expression was predominately detected in glandular epithelial cells of prostate by in situ hybridization analysis. The expression of PMEPA1 in LNCaP cells was induced by androgen in a time- and dose-specific manner. Evaluation of PMEPA1 expression in androgen-dependent/independent tumors of the CWR22 xenograft model revealed that PMEPA1 was overexpressed in three of four androgen-independent tumor tissues. These observations define PMEPA1 as a novel androgen-regulated gene exhibiting abundant expression in prostate tissue. The increased expression of PMEPA1 in relapsed tumors of the CWR22 model suggests activation of androgen signaling in hormone refractory disease. PMEPA1, along with other highly androgen-induced prostate-specific genes, has potential to serve as an androgen signaling read-out biomarker in prostate tissue., (Copyright 2000 Academic Press.)

Purpose: We determined the incidence of patient self-reported post-prostatectomy incontinence, impotence, bladder neck contracture and/or urethral stricture, sexual function satisfaction, quality of life and willingness to undergo treatment again in a large multicenter group of men who underwent radical prostatectomy. We also determined whether the morbidities of sexual function satisfaction, quality of life and bladder neck contracture and/or urethral stricture are predictable from demographic and postoperative prostate cancer factors., Materials and Methods: A self-reporting questionnaire was completed and returned by 1,069 of 1,396 eligible patients (77%) who underwent radical prostatectomy between 1962 and 1997. Of the respondents 868 (85.7%) underwent surgery after 1990 and in all prostatectomy had been done a minimum of 6 months previously. Questionnaire results were independently analyzed by a third party for morbidity tabulation and the association of patient reported satisfaction., Results: The patient self-reported incidence of any degree of post-prostatectomy incontinence, impotence and bladder neck contracture or urethral stricture was 65.6%, 88.4% and 20.5%, respectively. The incidence of incontinence requiring protection was 33% and only 2.8% of respondents had persistent bladder neck contracture or urethral stricture. Although incontinence and impotence significantly affected self-reported sexual function satisfaction, quality of life and willingness to undergo treatment again (p = 0.001), 77.5% of patients would elect surgery again. This finding remained true even after adjusting for demographic variables, and the time between surgery and the survey by multiple logistic regression., Conclusions: Although radical prostatectomy morbidity is common and affects self-reported overall quality of life, most patients would elect the same treatment again. Impotence and post-prostatectomy incontinence were significantly associated with sexual function satisfaction, quality of life and willingness to undergo treatment again. Bladder neck contracture and/or urethral stricture was associated with willingness to undergo treatment again after adjusting for demographic variables and time from surgery to the survey.

Objectives: Urologists routinely use the systematic sextant needle biopsy technique to detect prostate cancer. However, recent evidence suggests that this technique has a significant sampling error. Recent data based upon whole-mounted step-sectioned radical prostatectomy specimens using a 3-D computer assisted prostate biopsy simulator suggests that an increased detection rate is possible using laterally placed biopsies. A new 10-core biopsy pattern was shown to be superior to the traditional sextant biopsy. This pattern includes the traditional sextant biopsy cores and four laterally placed biopsies in the right and left apex and mid portion of the prostate gland. The objective of this study is to confirm the higher prostate cancer detection rate obtained using the 10-core biopsy pattern in a small cohort of patients., Methods: We retrospectively reviewed 35 consecutive patients with a pathologic diagnosis of prostate cancer biopsied by a single urologist using the 10-core biopsy pattern. The frequency of positive biopsy was determined for each core. Additionally, the sextant and 10-core prostate biopsy patterns were compared with respect to prostate cancer detection rate., Results: Of the 35 patients diagnosed with prostate cancer, 54.3% (19/35) were diagnosed when reviewing the sextant biopsy data only. Review of the 10-core pattern revealed that an additional 45.7% (16/35) of patients were diagnosed solely with the laterally placed biopsies. The laterally placed biopsies had the highest frequency of positive biopsies when compared to the sextant cores., Conclusions: Our results suggest that biopsy protocols that use laterally placed biopsies based upon a five region anatomical model are superior to the routinely used sextant prostate biopsy pattern. Lateral biopsies in the apex and mid portion of the gland are the most important.

Transrectal Ultrasonography (TRUS) based systematic needle biopsy of the prostate has been widely used clinically in the diagnosis of prostate carcinoma. Current protocols for prostate biopsy, such as the Sextant Protocol, however, have been proven to be insufficient in cancer detection since these protocols were built without having accurate information on 3D distribution of prostate cancers. In this research, our goal is to optimize prostate biopsy protocols by statistically investigating spatial distributions of prostate cancers. Based on the low-resolution nature of ultrasound imaging and the current clinical conventions, we propose to divide each individual prostate gland into different zones that are can be recognized and accessed by the urologists with ultrasound images during biopsy. By calculating cancer appearance inside each of these zones using a large number of prostate samples, we get the overall distributions of prostate cancers based on which an optimal biopsy protocol can be developed.

Background: Black race has been associated with a significantly increased risk of prostate cancer mortality. This exploratory analysis investigated the effect of race on the clinical outcome of combined androgen blockade (CAB)., Methods: Data for analysis were obtained from a double-blind, randomized, multicenter trial comparing CAB in the form of bicalutamide (50 mg once daily) or flutamide (250 mg three times daily) plus luteinizing hormone-releasing hormone analogs (LHRHa; goserelin acetate 3.6 mg, or leuprolide acetate 7.5 mg) in 813 patients with stage D(2) prostate cancer (median follow-up, 160 weeks). Patients were analyzed according to race (African American [AA], white, or other). The primary clinical events were disease progression and survival., Results: Four hundred and four patients received bicalutamide/LHRHa and 409 received flutamide/LHRHa. Although treatment with bicalutamide/LHRHa resulted in slightly longer time to progression and survival time in white and AA males than treatment with flutamide/LHRHa, the differences between the treatment groups were not statistically significant., Conclusions: No marked effect of race on clinical outcome was observed regardless of antiandrogen, suggesting that similar treatment benefits are to be expected in either race., (Copyright 1999 Wiley-Liss, Inc.)

Purpose: Black men with and without prostate cancer in general have higher prostate specific antigen (PSA) before screening and treatment than other racial groups. A preliminary study suggested that higher PSA levels may be primarily due to greater tumor burden. We compared PSA and 3-dimensional (D) tumor volume in a consecutive cohort of black and white radical prostatectomy patients in an equal access military health care setting to determine racial differences in these parameters., Materials and Methods: Prospective data collection, 2.25 mm. step section whole mount specimen processing and 3-D tumor volume assessment were performed in 226 patients with clinical stage T1-T3 prostate cancer undergoing radical prostatectomy at our center between April 1993 and March 1997. Of the patients 25 were excluded from further analysis because of neoadjuvant hormone treatment, T3 disease or Asian race. A total of 155 white and 46 black patients were compared., Results: There was no significant racial difference in the distribution of patients by age, clinical stage, pathological stage, Gleason sum or benign prostate gland volume. A significant racial difference was noted for pretreatment PSA and 3-D tumor volume. PSA values were higher in black men than in white men, and the racial difference remained statistically significant in multivariate analysis adjusting for 3-D tumor volume, benign gland volume, age, stage and Gleason sum., Conclusions: Racial difference in PSA persists, despite rigorous covariate adjustment, and further study is needed to explain this PSA difference.

Molecular genetic analyses of human prostate cancer (CaP) has revealed frequent loss of specific chromosome regions suggesting the presence of putative tumor suppressor gene(s) (TSG) on these chromosome loci whose inactivation may play a role in prostate tumorigenesis. To understand the role of 6q alterations in CaP, we have undertaken a comprehensive analysis of proximal 6q. Genomic DNA from tumor and normal prostate tissues from radical prostatectomy specimens of 38 patients were analyzed by polymerase chain reaction (PCR) for 13 polymorphic microsatellite loci on 6q. Allelic losses of 1 or more polymorphic loci were detected in 11 of 38 patients (29%). Six of 11 tumors showing any 6q deletion were found to have allelic losses at D6S1056 and D6S300 loci. Our results revealed a 1.5 megabase interval between D6S1056 and D6S300 at 6q16.3-21 as the minimal region of deletion, which may contain the putative TSG involved in prostate tumorigenesis. One of the tumor samples demonstrated homozygous deletion at a distal location D6S314 (6q23-24), suggesting another locus potentially associated with CaP. Although the relationship of 6q loss of heterozygosity (LOH) with various clinico-pathologic variables, i.e., cancer recurrence or pathologic stage, did not reveal a statistically significant association, the risk for 6q LOH to non-organ confined (pT3) disease was 5-fold higher than for organ confined disease.

Purpose: The reverse transcriptase polymerase chain reaction (RT-PCR) assay for prostate specific antigen (PSA) expressing cells in the blood circulation has been under intense investigation since 1992. Although it has been suggested that this technology could be used as molecular staging for occult prostatic hematogenous metastases, we have been unable to confirm RT-PCR PSA positivity of peripheral blood to predict stage or recurrence in radical prostatectomy cases. We performed bone marrow RT-PCR PSA assay on a large cohort of radical prostatectomy cases and evaluate the use of this assay in improving prostate cancer staging and detecting early recurrence., Materials and Methods: Unilateral anterior iliac crest bone marrow aspirates were performed on 116 patients immediately before radical prostatectomy between February 1995 and September 1997. Radical prostatectomy specimens were processed as whole mounts. A sensitive nested RT-PCR assay with specific primers derived from the PSA sequence was used, which enabled us to detect PSA expressing LNCaP prostate cancer cells at the sensitivity of 1 cancer cell per 10 million lymphocytes (1/10(7)). A minimum of 3 RT-PCR PSA reactions were performed on all patients and at least 2 positive tests were required to define positivity. Patients were followed for PSA recurrence (mean followup 14.7 months)., Results: PSA expressing cells were detected in bone marrow of 51 of 116 patients (44.0%) when at least 2 of 3 RT-PCR PSA assays per patient were positive. A much higher rate of RT-PCR PSA positivity was noted (77/116 patients, 66.3%) when any RT-PCR PSA positivity was considered. In 10 randomly selected cases the RT-PCR product was confirmed as PSA by deoxyribonucleic acid sequencing. Of 51 bone marrow RT-PCR positive cases 25 (49%) had organ confined disease and 26 (51%) had nonorgan confined disease. Similarly, bone marrow RT-PCR PSA was not associated with age, race, grade, pretreatment PSA or prostatic acid phosphatase value, clinical stage or margin status. However, the 2-year disease-free survival was 96.6% in RT-PCR negative patients versus 77.5% in RT-PCR positive patients (p = 0.054), and bone marrow RT-PCR PSA was an independent prognostic factor in multivariate analysis including PSA, Gleason grade and pathological stage., Conclusions: Bone marrow RT-PCR PSA positivity in this study did not predict pathological stage, grade or margin positivity as determined from whole mount prostate cancer specimens. Furthermore, no relationship with age, grade or serum markers and bone marrow RT-PCR PSA positivity was noted. However, bone marrow RT-PCR PSA was associated with early disease recurrence. Further studies and longer followup are warranted to define the metastatic potential of the PSA expressing cells in the bone marrow of prostate cancer patients.

Background: Combined androgen blockade for the treatment of metastatic prostate cancer consists of an antiandrogen drug plus castration. In a previous trial, we found that adding the antiandrogen flutamide to leuprolide acetate (a synthetic gonadotropin-releasing hormone that results in medical ablation of testicular function) significantly improved survival as compared with that achieved with placebo plus leuprolide acetate. In the current trial, we compared flutamide plus bilateral orchiectomy with placebo plus orchiectomy., Methods: We randomly assigned patients who had never received antiandrogen therapy and who had distant metastases from adenocarcinoma of the prostate to treatment with bilateral orchiectomy and either flutamide or placebo. Patients were stratified according to the extent of disease and according to performance status., Results: Of the 1387 patients who were enrolled in the trial, 700 were randomly assigned to the flutamide group and 687 to the placebo group. Overall, the incidence of toxic effects was minimal; the only notable differences between the groups were the greater rates of diarrhea and anemia with flutamide. There was no significant difference between the two groups in overall survival (P=0.14). The estimated risk of death (hazard ratio) for flutamide as compared with placebo was 0.91 (90 percent confidence interval, 0.81 to 1.01). Flutamide was not associated with enhanced benefit in patients with minimal disease., Conclusions: The addition of flutamide to bilateral orchiectomy does not result in a clinically meaningful improvement in survival among patients with metastatic prostate cancer.

This is a report of a low-grade ureteral carcinoma presenting as a pelvic mass in a postmenopausal woman with a prolonged history of lower back pain. A right complex adnexal mass and right hydroureter and hydronephrosis in an atrophic nonfunctioning right kidney was found during evaluation for the back pain. Operative evaluation revealed a normal uterus and ovaries; however, a 2 x 3-cm mass in the right ureter was found at the level of the uterine arteries. A total abdominal hysterectomy, bilateral salpingo-oophorectomy, and right nephroureterectomy were performed with pathology returning grade I papillary transitional cell carcinoma of the ureter.

Objectives: To describe current results with Western blot assay for prostate specific membrane antigen (PSMA) using 7E11.C5 antibody and the development of an additional antibody measurement for PSMA by a new sandwich immunoassay., Methods: A population of patients from a screening group, from a difficult diagnostic group, from a pre- and postoperative radical prostatectomy group, and from a group with metastatic disease followed for a serial period, provided the serum values for a prospective assessment of PSMA by Western blot assay. A new monoclonal antibody was sought, reacting to the C-terminal region of PSMA in order to develop a sandwich radioimmunoassay., Results: PSMA values in screened patients correlate with the more advanced stage of the cancers determined. In postprostatectomy patients, the PSMA value corresponds more with preoperative values and with the values of those with a poor clinical course. In difficult diagnostic cases, the PSMA value is increased, specifically in hormone-refractory cases and particularly in those cases judged by other criteria, such as the National Prostatic Cancer Project, to be in clinical progression compared with those judged to be in clinical remission. The level of PSMA value appears to be independent of homogeneous tumor volume and to be more related to that of prior hormone treatment, or to where prostate cancer cells can be documented to be outside the prostate. A new monoclonal antibody, 3F5.4G6, reacts with the extracellular domain of PSMA near the C-terminal region. This is in contrast to the previously measured antibody 7E11.C5, which reacts with an N-terminal epitope. 3F5.4G6 recognizes the same PSMA protein as does 7E11.C5. The epitopes are essentially at opposite ends of the molecule. The 3F5.4G6 antibody reacts with the LNCaP line but not with DU145, or PC3. These two antibodies to PSMA are well suited for use in a new sandwich immunoassay., Conclusions: PSMA provides a prostatic cancer serum test by using Western blot, which suggests a clinical prognostic value not seen with other markers. New antibodies, such as 3F5.4G6, reacting with the extracellular domain of PSMA combined with 7E11.C5, appear to offer an opportunity for a new sandwich immunoassay.

Purpose: Biostatistical models predicting the risk of recurrence after radical prostatectomy for clinically localized prostate cancer are necessary. Identifying these high risk patients shortly after surgery, while tumor burden is minimal, makes them candidates for possible adjuvant therapy and/or investigational phase II clinical trials. This study builds on previously proposed models that predict the likelihood of early recurrence after radical prostatectomy., Materials and Methods: In our analysis we evaluate age, race, prostatic acid phosphatase and nuclear grade with the established prognostic variables of pretreatment prostate specific antigen, postoperative Gleason sum and pathological stage., Results: After multivariable Cox regression analysis using only statistically significant variables that predicted recurrence we developed an equation that calculates the relative risk of recurrence (Rr) as: Rr = exp[(0.51 x Race) + (0.12 x PSAST) + (0.25 x Postop Gleason sum) + (0.89 x Organ Conf.). These cases are then categorized into 3 distinct risk groups of relative risk of recurrence of low (< 10.0), intermediate (10.0 to 30.0) and high (> 30.0). Kaplan-Meier survival analysis of these 3 risk groups reveals that each category has significantly different risks of recurrence (p < 0.05). This model is validated with an independent cohort of radical prostatectomy patients treated at a different medical center by multiple primary surgeons., Conclusions: This model suggests that race, preoperative prostate specific antigen, postoperative Gleason sum and pathological stage are important independent prognosticators of recurrence after radical prostatectomy for clinically localized prostate cancer. Race should be considered in future models that attempt to predict the likelihood of recurrence after surgery.

Purpose: We examine the clinical prognostic value of the currently available simple and inexpensive immunoenzymatic prostatic acid phosphatase (PAP) assay for the staging and prognosis of radical prostatectomy cases., Materials and Methods: Between February 1, 1990 and May 3, 1996 pretreatment PAP was measured in 295 patients who underwent radical prostatectomy. From February 1, 1990 to May 17, 1992 the Hybritech Tandem-E assay was used in 75 cases, from May 18, 1992 to February 28, 1993 the Abbott EIA assay was used in 49 and from March 1, 1993 to May 3, 1996 the Abbott IMx assay was used in 171. PAP assays were analyzed individually and the results were combined with pretreatment prostate specific antigen (PSA) values to assess the ability to predict organ confined prostate cancer and serological recurrence after radical prostatectomy., Results: PAP testing was not of value for predicting organ confined disease or positive margins. However, this test was useful for predicting the first serological PSA recurrence in the 3 periods (77 to 85% correct) and overall (82% correct, p < 0.001, odds ratio 6.06). The Kaplan-Meier disease-free survival rate at 4 years was 78.8% for men with PAP less than 3 ng./ml. and 38.8% for those with PAP 3 ng./ml. or greater, which was significant when pretreatment PSA was less than 10 ng./ml. (p = 0.047), 10 ng./ml. or greater (p = 0.012) and overall (p < 0.001). PAP testing added prognostic information to pretreatment PSA values and it was an independent predictor of recurrence., Conclusions: The widely available and inexpensive PAP assays of the 1990s are predictors of recurrence after radical prostatectomy. They should be included in future studies of prostate cancer recurrence modeling. However, they do not predict pathological stage or margin status.

Background: Clinical and pathological staging of prostate cancer has been, and remains, problematic. Since prostate-specific antigen (PSA)-detected tumors are often discerned during "screening," what are their significance?, Methods: We analyzed 67 consecutive patients with stage T1c prostate cancer undergoing radical prostatectomy at our institution from August 1, 1991-September 12, 1995, and who had whole-mount specimen processing. Diagnosis was determined in all cases by transrectal ultrasound-guided biopsy., Results: The mean age of our patients was 63 years, and the mean PSA at time of diagnosis was 8.6 ng/ml (median, 7.2 ng/ml). There was organ-confined cancer in 31/67 (46%) patients; 17/67 (25%) had periprostatic fat infiltration, and of these 5(7%) had seminal vesicle involvement. Thirty-one of 67 (46%) had positive surgical margins. Twenty-two (33%) had a Gleason sum of > or = 7 in the final pathological specimen. Insignificant tumors (dominant tumor volume < 0.20 cc) were found in only 4 cases. Smaller tumors were more likely to be found when the PSA was < 10 ng/ml. Multifocal disease was found in 64/67 (96%) prostate specimens., Conclusions: This study adds impetus to the growing realization that nonpalpable prostate cancer, detected because of elevated PSA, is rarely insignificant. Our findings add further emphasis to the fact that patients diagnosed by PSA elevation have, for the most part, significant cancer that should be treated aggressively.

We have previously described potent growth-inhibitory effect of a recombinant adenovirus expressing wild type p53 (AdWTp53) in metastatic prostate cancer cells via activation of cellular p53 pathways. We have extended these observations to analyze the effects of AdWTp53 on primary cultures of radical prostatectomy specimens (RPS) and have also evaluated the gene therapeutic potential of the AdWTp53 in a nude mice model. Infection of primary cultures of prostate cancer specimens resulted in about 80% cell growth inhibition in comparison with cultures treated with control adenovirus dl312. Single injection of AdWTp53 into pre-established tumor nodules of DU145 prostate cancer cells suppressed tumor growth significantly (p = 0.0407) as determined by comparison of tumor volumes of the AdWTp53-treated vs. control vector (dl312) or PBS-treated groups. Moreover, there was no significant difference in tumor growth inhibition between single vs. multiple injections of AdWTp53. Our observations support the potential of AdWTp53 for gene therapy of prostate cancer.

Background: Approximately 50-60% of patients treated with radical prostatectomy for clinically localized prostate carcinoma are found to have microscopic disease that is not organ-confined, and a significant portion of these patients will relapse. Multiple studies have attempted to identify these high risk patients by evaluating many potential prognostic variables. These studies, however, have not included the more recent molecular biomarkers found to be independent predictors of disease recurrence., Methods: One hundred thirty-two patients who underwent radical prostatectomy at one center between 1986 and 1993 were subjected to a multivariable Cox regression analysis to determine the preoperative and postoperative variables that remain significant predictors for the likelihood of serologic recurrence. The preoperative variables included in the model were age, race, and prostate specific antigen(PSA); the postoperative variables were Gleason sum, nuclear grade, pathologic stage (capsular status), p53 tumor suppressor gene expression, bcl-2 protooncogene expression, and proliferative biomarker Ki-67 expression. Biomarkers were also evaluated separately., Results: A model was developed using only variables that remained significant predictors for the likelihood of recurrence. The following equation calculated the relative risk of recurrence: Rw = exp [(0.70 x Race) + (0.79 x PSA[4.1-10]) + (1.34 x PSA[>10]) + ( 0.91 x Organ confinement) + (0.65 x p53[1,2+]) + (1.45 x p53[3,4+]) + (0.70 x bcl-2)]. This equation categorized men into 3 distinct risk groups (low: Rr < 5.0; intermediate: Rr = 5.0-15.0; high risk: Rr > 15.0)., Conclusions: This equation allows patients at high risk for PSA recurrence to be identified shortly after radical surgery. These patients at high risk for serologic recurrence and eventual progression may be considered for currently accepted adjuvant therapy or enrollment in clinical trials for the newer investigational therapies for locally advanced prostate carcinoma.

Background: The p16 gene product is a negative regulator of cell cycle and has been shown to be deleted or mutated in a number of tumor cell lines and primary tumors. The role of p16 in prostate cancer is not defined. Prostate cancer tissues and cell lines were evaluated for p16 gene alterations., Methods: Five metastatic prostate cancer cell lines were analyzed for p16 gene structure and its expression by Southern and Northern blot analyses. Forty-one DNA specimens from 18 microdissected primary tumor specimens, adjacent normal tissues, and cell lines were amplified by polymerase chain reaction for p16 protein coding and splice junction sequences. Mutations were analyzed by single strand conformation polymorphism and DNA sequencing., Results: DU 145 cell line exhibited a missense mutation in codon 84 (GAC to TAC). With the exception of previously reported polymorphism, no mutation was detected in p16 coding or splice junction sequences in primary prostate cancer specimens., Conclusions: Inactivation of p16 gene by mutations in the protein coding sequence does not play a major role in the genesis of primary prostate cancer.

Purpose: Pure testicular teratoma is rare in adulthood with an incidence of 5%. Pure teratoma is considered less aggressive and less likely to metastasize than other nonseminomatous germ cell tumors. Therefore, patients with mature teratoma have been considered candidates for surveillance protocols. We report our experience with 44 cases of primary pure testicular teratoma., Materials and Methods: We retrospectively identified 44 patients (5.7%) with primary pure teratoma of the testis of the 772 treated for testicular germ cell tumors at our institutions. Archival tumor blocks were available for pathological reevaluation and serial sections were obtained in all cases. A total of 35 patients (79.5%) who presented with clinical low stage disease, including stage I in 26 (59.1%) and stage IIA/B in 9 (20.4%), underwent radical orchiectomy followed by retroperitoneal lymphadenectomy. Nine patients (20.5%) who presented with clinically advanced disease (stages IIC to IV) were treated with primary chemotherapy and secondary retroperitoneal lymphadenectomy of residual masses., Results: The frequency of lymph node metastases was 19.2% in clinical stage I disease and 66% in stage IIA/B. Histopathological diagnosis of mature teratoma was confirmed in all cases. However, of 20 patients 16 (80%) had scars or calcifications in the adjacent parenchyma, indicating a burned out tumor, and 4 (20%) had microfocal embryonal carcinoma. None of the patients with clinical stage I disease had relapse during followup and the relapse rate in those with stage IIA/B disease was 33%. Median followup was 97 months (range 24 to 250). Overall 43% of patients with pure teratoma presented with metastatic disease., Conclusions: Our data demonstrate the malignant potential of pure testicular mature teratoma. Based on our results metastases in testicular mature teratoma seem to result from metastasizing nongerm cell components undergoing early regression, as demonstrated by the high frequency of burned out tumors. We recommend that serial sections be taken of the orchiectomy specimen in all cases of pure mature teratoma to determine adequate management: retroperitoneal lymphadenectomy in cases of associated scars, calcifications or microfocal malignant germ cell components and surveillance in cases of pure mature teratoma.

There is no debate that both the earlier diagnosis and the treatment of men with cancer of the prostate (CaP) are having an impact on patients with this disease. In many practices there are fewer and fewer patients presenting with the classic diagnosis of 'advanced disease', i.e., stage M (D2). Only a few years ago, a large percentage of men with CaP had bony metastases when they presented to a physician. Hormonal ablation was the optimal treatment, and the only question was whether bilateral orchiectomy or medical castration should be used. The median time to progression with either type of monotherapy was 12-18 months, and the median time to survival was 24-36 months. Unfortunately, in many parts of the world, this scenario is still the norm. In the United States, Europe, and an increasing number of other countries, improved methods of detection with transrectal ultrasound and prostate-specific antigen (PSA) have resulted in a dramatic shift in the stage of disease at diagnosis. It is safe to say that in these countries the majority of prostate cancers are now being clinically diagnosed while still localized, and many organ-confined tumors are being definitively treated and cured. Nevertheless, many of these patients will be understaged at the time of diagnosis and will show progression following definitive therapy. In most surgical series approximately one half of patients will be found on pathologic examination to have pT3 disease. The use of PSA in the diagnosis of CaP has been mentioned, and it is being used extensively to monitor recurrent/residual disease. Hormonal therapy is being employed earlier in numerous clinical situations, and its use is no longer reserved solely for patients with metastatic disease. In this context combined androgen blockade has become the gold standard of treatment in neoadjuvant situations as well as for advanced CaP. Newer advances, including 3-month depot formulations of luteinizing hormone-releasing hormone analogues, the reversibility of medical castration, the preference of most patients to have medical castration, and the approval of other antiandrogens in the United States, all have further strengthened the use of combined androgen blockade. Hormonal therapy in adjuvant settings, when there is a high likelihood of disease recurrence, is also being used in many clinical situations. In addition, there appears to be a role for certain types of hormonal therapy in chemoprevention.

Objectives: We prospectively evaluated whether free PSA improves the specificity of PSA and can be useful as a clinical guide to avoid repeat prostate biopsies in patients with persistent PSA elevations, normal digital rectal examinations, and previous negative prostate biopsies., Methods: Sixty-seven men with persistent PSA elevations (median 9.5, range 4.1-24.8 ng/mL), normal digital rectal examinations and two or more prior sextant biopsies (mean 2.8) had serum collected for measurement of total and free PSA. All patients were rebiopsied to determine the receiver operating characteristics of total PSA versus percent free PSA for prostate cancer detection., Results: The study biopsy identified 11 prostate cancer cases. The median percent free PSA was significantly higher at 18.0% among men without prostate cancer compared to 6.7% in men with prostate cancer (P < 0.00005). When sensitivity was plotted against 1-specificity, the area under the receiver operating characteristic curve for percent free PSA was 0.93, compared to 0.69 for free PSA density, 0.66 for PSA density, and 0.51 for PSA. In patients with elevated total PSA levels, normal digital rectal examinations and two prior negative sets of sextant prostate biopsies, a cutoff of 10% free PSA would maintain sensitivity at 91% with a corresponding specificity of 86%., Conclusions: Selective measurement of percent free PSA can significantly improve the specificity of prostate cancer screening with PSA. A low percent free PSA (< 10%) appears to be a powerful predictor of prostate cancer even after two negative prostate biopsies.

Purpose: The tumor suppressor gene (TSG) p53 and the proto-oncogene bcl-2 have been shown to be involved in the regulation of cell growth and apoptosis and have been implicated in hormone refractory prostate cancer (PC) and poor prognosis. The goal of this study was to determine the clinical utility of the presence of p53 and bcl-2 immunohistochemical (IHC) protein in the primary tumor as predictors of disease progression following radical prostatectomy (RP)., Materials and Methods: The expression of p53 and bcl-2 was evaluated in archival paraffin-embedded RP specimens from 175 patients followed from 1 to 9 years (mean = 4.6 years) and correlated with stage, grade, race and serologic (PSA) recurrence following surgery., Results: Overexpression of bcl-2 was noted in 47 of 175 (26.9%) patients; these patients had a significantly higher 5-year failure rate than those who did not overexpress bcl-2 (67.0% versus 30.7%). Expression of p53 was noted in 114 of 175 (65.1%) patients with a 5-year failure rate of 51.1% compared with a 5-year failure rate of only 22% in p53 negative patients. When expression rates for p53 and bcl-2 were combined, the 5-year failure rate was 75.3%. Conversely, when both p53 and bcl-2 IHC staining were negative, the 5-year failure rate was 20.4%. Univariate Kaplan-Meier analysis showed a statistically significant difference between p53 and bcl-2 positive and negative patients (p < 0.001). Multivariate Cox Regression Analysis with backward elimination controlling for age, race, stage and grade showed both p53 (p = .0185) and bcl-2 (p = .004) to be independent predictors of disease-free survival., Conclusion: p53 and bcl-2 appear to be important biomarkers that predict recurrence in clinically localized PC after RP.

Purpose: We assessed the cellular proliferation of clinically localized prostate cancer by immunohistochemistry using the monoclonal antibody MIB to Ki-67 antigen in an attempt to identify associations between proliferative indexes and disease progression following radical prostatectomy., Materials and Methods: Ki-67 proliferative antigen was evaluated using MIB 1 monoclonal antibody in archival paraffin embedded radical prostatectomy specimens from 180 patients followed for 1 to 9 years (mean 4.4). The percentage of tumor nuclei expressing Ki-67 antigen was measured and assigned and MIB 1 score (none or rare--negative, 1+--low score and 2 to 4+--high score) and analyzed for prostate specific antigen, stage, age, race, grade and serological recurrence postoperatively., Results: There was a significant association between MIB 1 score and nuclear grade (p < 0.001), Gleason score (p < 0.001) and pathological stage (p = 0.01). Patients with a high MIB 1 score had earlier progression and a lower 5-year recurrence-free survival rate (44%) than those with negative MIB 1 scores (71%, p < 0.001). In multivariate Cox regression analysis with backward elimination, pathological stage (p < 0.01), pretreatment prostate specific antigen (p = 0.04) and MIB 1 score (p = 0.05) were statistically significant predictors of disease-free survival, and patients with a high MIB 1 score were 3.1 times as likely to have recurrence as those with a negative score. Controlling for stage, patients with organ confined disease and a high MIB 1 score had a lower 5-year disease-free survival rate (68%) than those with a low MIB 1 score (95%, p < 0.01)., Conclusions: Proliferative activity as measured by the Ki-67 proliferative antigen, MIB 1, appears to be a prognostic marker of recurrent prostate cancer after radical prostatectomy.

Background: Two new prostate cancer markers, free-prostate specific antigen (f-PSA) and prostate specific membrane antigen (PSMA) were recently introduced. This report summarizes a prospective two-year multicenter test of their diagnostic or prognostic capabilities. Total PSA was also measured., Methods: There were four clinical groups studied: (1) 226 individuals from a screening project undergoing ultrasound and biopsy evaluation had markers obtained: (2) 68 patients suspected of having prostate cancer and undergoing 2 or more biopsies had the markers obtained on multiple occasions: (3) 100 patients undergoing radical prostatectomy had markers obtained pre- and post-operatively: and (4) 31 patients with metastatic prostate cancer each had multiple samples for marker assay obtained over a 2-year period. In all, 465 patients had one or more samples obtained and studied., Results: Free-PSA affords little additional diagnostic advantage compared with total PSA in the screening population. The receiver operating characteristic curves for diagnostic accuracy were ranked: (1) PSA density; (2) total PSA; (3) f-PSA; and (4) PSMA, PSMA showed the best correlation with stage of the primary tumor in the screened group. In the multiple negative biopsy group, f-PSA varied from 12 to 21%. PSMA values were evaluated in all histologic categories. PSA density was > or = 0.15 in all categories. In the prostatectomy cases PSA values postoperatively were quite low in Stage II; f-PSA was of no value. Later, f-PSA was increased in association with elevated total PSA values. Mean PSMA values were above normal in all postoperative time periods except in Stage III patients at 6 months to 1 year postoperatively. PSA densities were all > or = 0.15. In patients with metastatic carcinoma, elevated PSMA values correlated best with a poor prognosis (clinical progression), as has been described., Conclusions: These data suggest that f-PSA values do not provide additional diagnostic benefit compared with total PSA in screening populations, in the presence of suspected cancer, postprostatectomy, or in metastatic disease. PSMA is of prognostic significance, especially in the presence of metastatic disease, and correlates well with the stage of disease in cancers detected in a screened population.

Background: Protein expression in the primary tumor of the tumor suppressor gene p53 and the proto-oncogene bcl-2 have been shown to be prognostic biomarkers of cancer recurrence after radical prostatectomy in patients with clinically localized prostate cancer. Cancer cell proliferation as measured by immunohistochemical markers such as the MIB-1 antibody for Ki-67 has recently been suggested to be of prognostic value in prostate cancer. The goal of this study was to determine the clinical use of p53, Ki-67 (MIB-1), and bcl-2 immunohistochemical protein expression in the primary tumor as combined predictors of disease progression after radical prostatectomy (RP)., Methods: Protein expressions of p53, Ki-67, and bcl-2 were evaluated in archival paraffin-embedded RP specimens from 162 patients monitored from 1 to 10 years (mean, 4.5 years) and correlated to stage, grade, race, and serologic (prostate-specific antigen) recurrence after operation., Results: Expression was detected in 112 (69.1%), 44 (27.2%), and 62 (38.3%) of 162 patients for p53 (1+ or greater), bcl-2 (1+ or greater), and Ki-67 (2+ or greater), respectively. Biomarker expressions were not correlated to age and race; however, all increased with increasing stage and grade. The degree of expression by percentage of malignant cells staining correlated to recurrence for p53 and Ki-67 but not for bcl-2. All three markers were correlated to raw and Kaplan-Meier recurrence by means of univariate analysis with recurrence estimates at 6 years of 60.7% versus 24.2%, 84.2% versus 38.6%, and 72.4% versus 30.6% comparing positive versus negative expression of p53, bcl-2, and Ki-67, respectively. p53 and bcl-2 remained as independent prognostic markers by Cox multivariate regression analysis. Although Ki-67 did not remain an independent marker, it added prognostic use in certain subsets of patients., Conclusions: p53, bcl-2, and Ki-67 (MIB-1) appear to be important biomarkers to predict recurrence in patients with clinically localized prostate cancer after RP, and all three biomarkers deserve further study.

Objectives: To analyze the relationship of age and race to prostate-specific antigen (PSA) levels among participants in a community-based study., Methods: A total of 77,700 records of men aged 40 to 79 years were analyzed from a longitudinal study of PSA conducted during Prostate Cancer Awareness Week 1993 and 1994. Records from 1994 were not included for men who were tested in 1993. All cases of prostate cancer were excluded. Records with outlier PSA values greater than 20 ng/mL were eliminated from the analysis (n = 190; 24%)., Results: Mean PSA values (ng/mL) of 10-year age groups differed significantly (P < 0.0001) between each group (ages 40-49, 0.83; 50-59, 1.23; 60-69, 1.83; 70-79, 2.31). In each successively older age group, PSA variance increased significantly (P = 0.0001). Standard deviations (SD) by age group were: 40-49, 0.79; 50-59, 1.33; 60-69, 1.94; and 70-79, 2.35. Significant differences in mean PSA by race were found. Pairwise differences in mean PSA were found between whites and blacks, whites and Latinos, blacks and Asians, and Asians and Latinos (P < 0.0001). No statistically significant differences in PSA variance between racial groups were found. Age-within-race analysis resulted in consistent statistical significance when comparing variance among age cohorts in each race., Conclusions: Age-specific PSA reference ranges are a result of the increasing mean PSA and increasing PSA variance in successively older cohorts of men. Mean PSA values differ significantly by race, but differences in PSA variance do not. The clinical significance of race-specific PSA reference ranges has yet to be determined.