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J W Moul

Publications and source records attributed to J W Moul.

At least 19 recordsLinked to original sources

Prostate-specific antigen to predict outcome of external beam radiation for prostate cancer: Walter Reed Army Medical Center experience, 1988-1995.

OBJECTIVES: To assess the ability of pretreatment and post-treatment prostate-specific antigen (PSA) measurements, clinical tumor stage, tumor grade, Gleason sum, race, age, and radiation dose to predict the recurrence of prostate cancer following external beam radiation therapy (XRT) since the introduction of PSA as a tumor marker at one tertiary care center. METHODS: The recurrence of prostate cancer among 371 evaluable patients of 389 patients treated with XRT at Walter Reed Army Medical Center was analyzed using Kaplan-Meier survival methodology and Cox multivariable regression models. Serologic (PSA) recurrence was determined using three consecutive rises in PSA after a nadir value. Clinical recurrence was defined as local recurrence (palpable or positive biopsy) and/or distant (radiographically evident) recurrence. Mean and median follow-up is 40.2 and 39.4 months, respectively (range 3.0 to 89.5), and minimum follow-up is 18 months for patients who were alive at the time of analysis. No patient received adjuvant hormonal therapy. Potential prognostic factors evaluated are pretreatment PSA, PSA nadir, age, race, clinical tumor stage, tumor grade, Gleason sum, and radiation dose. RESULTS: Of the 371 evaluable patients, 125 had disease recurrence. The Kaplan-Meier 5-year disease-free survival (DFS) rates for significant pretreatment variables in univariate analyses are as follows: pretreatment PSA less than 4 (79%), 4.1 to 10 (67%), 10.1 to 20 (57%), 20.1 to 50 (27%), and more than 50 (0%); for clinical tumor Stage T1a-T1c (84%), T2a-T2c (51 %), and T3-T4 (29%); for tumor grade well (58%), moderate (58%), and poor (30%). Four-year DFS rates for Gleason sum are 2 to 4 (82%), 5 (72%), 6 (56%), and 7 to 10 (48%). In multivariable Cox regression analysis with backward elimination of nonsignificant variables, age, race, tumor grade, and radiation dose were eliminated, leaving pretreatment PSA, clinical tumor stage, and Gleason sum as significant prognostic factors. Analysis of a Cox model that included nadir PSA as a time-dependent variable showed it to be the strongest prognostic factor variable in the analysis. CONCLUSIONS: XRT remains a suitable treatment modality for patients with pretreatment PSA less than 20.0, clinical tumor Stages T1-T2, and Gleason sum 2 to 6 prostate cancer. Patients achieving a nadir value less than 0.5 have more durable treatment outcomes.

Aged

Detection of circulating prostate specific antigen expressing prostatic cells in the bone marrow of radical prostatectomy patients by sensitive reverse transcriptase polymerase chain reaction.

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.

Aged

Prognostic risk factors that identify patients with clinical stage I nonseminomatous germ cell tumors at low risk and high risk for metastasis.

BACKGROUND: The purpose of this study was to develop a reliable model to identify clinical Stage I nonseminomatous germ cell tumors (NSGCTs) associated with low risk or high risk for occult retroperitoneal metastasis, so that the model could be used to customize the therapeutic approach for patients with these tumors. The model was to be based on pathohistologic parameters and immunohistochemical expression of proliferation markers, proteases, and adhesion molecules in the primary tumor. METHODS: One hundred forty-nine patients with clinical Stage I NSGCTs underwent retroperitoneal lymphadenectomy and were included in the study. Three to five paraffin embedded, formalin fixed tissue blocks were available from each patient and were analyzed for the following histopathologic features associated with pathologic Stage I or II disease: the presence or absence of vascular invasion (VI), the presence or absence of tunic invasion, and the percentage of each histologic type present in the primary tumor. Immunohistochemical expression of MIB-1, p53, bcl-2, cathepsin D, and E-cadherin was evaluated using a semiquantitative scoring system. Statistical analysis was performed with univariate and multivariate logistic regression models. RESULTS: The percentage of embryonal carcinoma (%EC, P < 0.001) and the presence of VI (P < 0.0001) and tunic invasion (P < 0.002) were the most significant independent risk factors associated with pathologic Stage II disease. A combination of %EC and VI allowed correct prediction of final pathologic stage for 88% of clinical Stage I patients. Cutoff values including both variables identified the correct pathologic stage for 131 of 149 patients (88%). Less than 45% EC and the absence of VI correctly identified pathologic Stage I disease in 91.5% of patients; more than 80% EC and the presence of VI correctly predicted pathologic Stage II in 88%. In univariate analysis, only p53 (P < 0.03) and E-cadherin (P < 0.001) expression were significantly different in the embryonal carcinoma component of pathologic Stage I and II NSGCT. To evaluate prospectively the clinical utility of the new derived cutoff points, the data were applied to 10 consecutive patients with clinical Stage I NSGCT who underwent retroperitoneal lymphadenectomy; pathologic Stage I and II were correctly predicted for 5 of 6 Stage I and 4 of 4 Stage II patients, respectively. CONCLUSIONS: %EC and the presence or absence of VI appear to be reliable prognosticators to identify patients at high risk and low risk for occult retroperitoneal disease. In cases of clinical Stage I NSGCT, p53, bcl-2, MIB-1, cathepsin D, and E-cadherin did not appear to be of prognostic significance. The authors recommend that all patients with clinical Stage I NSGCT have their primary orchiectomy specimens evaluated for %EC and the presence of VI to determine their risk for occult retroperitoneal metastasis.

Antigens, Nuclear

Perineal seeding of prostate cancer as the only evidence of clinical recurrence 14 years after needle biopsy and radical prostatectomy: molecular correlation.

Perineal needle tract seeding of prostate cancer is an unusual complication of perineal prostate biopsy. We report a case with the longest known interval from biopsy to perineal recurrence--14 years. The prostate-specific antigen did not become detectable until 12 years after biopsy and no other metastases were apparent, suggesting that the patient's perineal disease was an isolated recurrence. Immunohistochemical staining of the perineal recurrence and the original biopsy and prostate for the p53 tumor suppressor gene and bcl-2 oncogene proteins revealed rare/absent p53 expression but marked increased bcl-2 expression. This unusual molecular pedigree may help to explain this rare clinical scenario.

Aged

Significance of familial history of prostate cancer to traditional prognostic variables, genetic biomarkers, and recurrence after radical prostatectomy.

OBJECTIVES: Prostate cancer (PCa) has a familial predisposition imparting an increased risk of developing the disease in those with a family history. The pathologic characteristics are similar to sporadic cases; however, the disease-free survival rates of hereditary PCa have recently been disputed, with one major study suggesting that familial cases have higher recurrence rates. Our study seeks to support or refute this association and to evaluate the genetic biomarkers p53, bcl-2, Ki-67, and neovascularity between familial and sporadic disease. METHODS: We retrospectively reviewed data of 573 patients who underwent radical prostatectomy over an 11-year period. Of these, 474 patients had known family history data. Univariable statistical analysis using the Pearson chi-square test and Kaplan-Meier disease-free survival analysis was performed to identify any correlation between the tested variables and family history. Smaller subsets of this cohort that had available archival material for immunohistochemical staining and family history data were analyzed in a similar manner. RESULTS: The preoperative variables (prostate-specific antigen, prostatic acid phosphatase, clinical stage, highest biopsy Gleason sum, and glandular differentiation) and postoperative variables (stage, highest Gleason sum, and glandular differentiation) did not correlate with family history. Kaplan-Meier disease-free survival analysis revealed no differences between sporadic and familial cases. The analysis of p53, bcl-2, Ki-67, and angiogenesis revealed that only increasing p53 expression and positive family history of PCa approached significance (P = 0.057). CONCLUSIONS: Prognostic variables routinely used in PCa and selected genetic biomarker immunostaining abnormalities are not significantly different in men with and without a family history of PCa. Disease-free survival after radical prostatectomy is also unaffected by family history.

Aged

Reference ranges for serum prostate-specific antigen in black and white men without cancer.

OBJECTIVES: To determine the age- and race-specific prostate-specific antigen (PSA) distributions in healthy men in central South Carolina and to compare these to data from other studies. METHODS: Two thousand ninety-two black men aged 40 to 69 years and white men aged 50 to 69 years from the general population in 11 counties of central South Carolina participated in a prostate cancer educational program. Seventy-two percent of the participants were black-about double the proportion in the general population-and 63% of the men (1319 of 2092) subsequently obtained a PSA determination from their own physician. The distribution of serum PSA was compared with distributions from the Olmsted County study and from the Walter Reed Army Medical Center/Center for Prostate Disease Research study. RESULTS: Older men without cancer had higher PSA levels. Regression analyses yielded an associated increase of about 3.3% per year. Reference ranges for normal PSA in men without cancer (based on their sample 95th percentiles) were zero to 1.9, 3.8, and 5.7 ng/mL in black men aged 40 to 49, 50 to 59, and 60 to 69 years, and zero to 2.7 and 4.9 mg/mL in white men aged 50 to 59 and 60 to 69 years, respectively. CONCLUSIONS: Reference ranges for normal serum PSA levels should take into account the population from which they are derived and to which they will be applied. Reference ranges that are useful in the general population can differ from those that are appropriate in a hospital setting. For the general population in central South Carolina, reference ranges for serum PSA levels are lower than previously published reference ranges, particularly among black men.

Adult

New tumor markers of testis cancer.

Potential tumor markers for testis cancer have become numerous with the new molecular techniques available. New protein markers have been evaluated, and histologic factors have shown correlations with stage of disease. Cytogenetic analysis studies have also shown associations with stage progression. Chromosomal markers, oncogenes, and tumor suppressor genes are possible candidates for tumor markers. These new potential tumor markers may become as commonplace as the established markers and may enhance diagnosis, staging, and treatment of testis cancer.

Biomarkers, Tumor

Efficacy of multiple administrations of a recombinant adenovirus expressing wild-type p53 in an immune-competent mouse tumor model.

Infection of Renca cells in vitro with a recombinant adenovirus expressing a marker gene beta-galactosidase resulted in high level of the transgene expression. Renca tumors grown in Balb/C mice were also infectable with this recombinant adenovirus. The transgene expression in the tumors lasted for about 7 days, however, administration of another dose of Ad-beta gal, on day 7 produced beta-galactosidase expression. To investigate the effect of antibodies to adenovirus, animals were injected with multiple doses of adenovirus to produce neutralizing antibodies. To these animals Renca cells were injected and tumors formed. Interestingly, when Ad beta-gal was administered into these tumors, a high level of transgene expression was still observed. We next explored the utility of a recombinant adenovirus expressing p53 (AdWTp53) in the Renca tumor model. Renca cells when exposed to an adenovirus expressing p53 (AdWTp53) produced a high level of p53 protein, a p53-inducible gene p21/WAF1/Cip1 and underwent apoptosis. A single injection of AdWTp53 (10(9) plaque forming units) resulted in significant inhibition of tumor growth. However, multiple administrations (four doses of 2.5 x 10(8) plaque forming units) of AdWTp53 were needed for tumor cures. Mixing uninfected and AdWTp53-infected cells showed a bystander effect of AdWTp53-infected Renca cells. Based on these results we believe that an appropriate dose scheduling of AdWTp53 can be efficacious for cancer gene therapy in immune-competent tumor-bearing animals.

Adenoviridae

Immunohistochemical expression of monoclonal antibody 43-9F in testicular germ cell tumours.

The aim of this study was to evaluate the clinical utility of immunohistochemical staining of human testicular germ cell tumours with the monoclonal antibody 43-9F to distinguish embryonal carcinoma (EC) from other malignant germ cell components in order to facilitate pathohistological assessment of prognostic risk factors for metastatic disease in clinical stage I NSGCT. Archival, formalin-fixed, paraffin-embedded tissue blocks of 24 classical seminomas, 7 spermatocytic seminomas, and 20 non-seminomatous germ cell tumours were stained for 43-9F, AFP, hCG and PLAP expression. Immunohistochemical expression was graded using a semi-quantitative scoring system: 1+ = 0-25%, 2+ = 26-50%, 3+ = 51-75% and 4+ = 76-100%. Positive immunohistochemical staining for 43-9F was found in all embryonal carcinomas and yolk sac tumours (YST); staining intensity was not statistically different between the two tumours (3.8 +/- 1.2 vs. 3.1 +/- 0.9). Classical seminomas and seminomatous components of NSGCT stained positive in 13/24 cases (54%); staining intensity was weak to moderate (1.1 +/- 0.7) in all but two cases (4+). Spermatocytic seminomas demonstrated weak positive immunostaining in 2/7 cases (29%). Adjacent CIS was found in 33/54 (61.1%) of tumours and 24/33 (72.7%) of CIS cells exhibited a weak to moderate staining intensity (1.4 +/- 0.7). AFP expression was found in 93% of YST and in only 10% of EC; however, based on the focal staining pattern, adequate differentiation of YST and EC was not possible. Positive PLAP staining was observed in 75% of EC, 79% of seminomas and in 88% of CIS cells. We did not find 43-9F staining clinically useful to distinguish embryonal carcinoma from other germ cell tumour components such as yolk sac tumour. The detection rate of CIS by 43-9F immunohistochemical staining was low and combination of PLAP staining with light microscopy was even superior. Additionally, our study confirms the link between pre-invasive CIS and embryonal carcinoma and suggests the possible direct development of embryonal carcinoma from CIS.

Alkaline Phosphatase

Molecular analysis of P16(Ink4)/CDKN2 and P15(INK4B)/MTS2 genes in primary human testicular germ cell tumors.

PURPOSE: p16 (MTS 1) and p15 (MTS 2) are negative regulators of cell cycle progression at the G1 cell cycle checkpoint and function as tumor suppressor genes (TSG). Both p15 and p16 are located on chromosome 9p21 and alterations have been demonstrated in a variety of human malignancies and human cancer cell lines. In testicular germ cell tumors (TGCT) loss of heterozygosity of 9p21 to 23 has been observed in 41% to 72% of informative cases. The aim of our study was to examine TGCT and testicular cancer cell lines for deletions and mutations of the p15 and p16 genes. MATERIALS AND METHODS: 24 testicular germ cell tumors, 4 testicular cancer cell lines (TERA I, TERA II, HTE, HTH), 8 benign testicular tumors and 9 samples of normal testicular parenchyma were examined. Examinations for loss of heterozygosity (LOH) on 9p21 were performed for IFNA, D9S171, D9S126, D9S161, D9S1748 and PKY9 locus using Southern Blot analysis. Southern Blot analysis of the p16 gene to examine gross alterations was done using random primer labeled p16 cDNA. In addition all samples were examined for mutations of exons 1 to 3 of p16 and exons 1 to 2 of p15 by polymerase chain reaction (PCR) followed by single strand conformation polymorphism (SSCP) analysis on MDE-gels. All observed band shifts on SSCP were further evaluated by direct DNA sequencing techniques. RESULTS: No major deletions were detected for p16 and p15. 42% of all TGCT demonstrated LOH of the IFNA locus, 16% of the D9S161 locus and 5.5% of the D9S171 locus. No LOH was seen for the D9S126 locus. 5/24 TGCT (21%) and 1 testicular cancer cell line (TERA II) demonstrated band shifts for exon 2, 8/24 TGCT (33%) and 1 testicular cancer cell line (TERA I) showed band shifts for exon 3; 4 TGCT had an allelic loss for exon 3 on SSCP. DNA sequencing analysis for exon 2 demonstrated a single base substitution (G-->A) in codon 140 resulting in an amino acid exchange (ala-->thre) in 4 cases and a single base deletion with frame shift mutation in codon 142 in 2 cases. DNA sequencing analysis for exon 3 demonstrated a polymorphism in intron 2 in all cases. For p15 no band shifts were observed for exons 1 to 2 in TGCT or testicular cancer cell lines; none of benign testicular tumors or normal control tissues demonstrated any band shifts for p15 or p16. DISCUSSION: We demonstrated a high frequency of mutations for exon 2 in specimens of primary testicular germ cell tumors, but not in benign tumors or normal controls. We therefore believe that p16 might be involved in the pathogenesis of human TGCT. The polymorphisms described for exon 3 might be utilized for further LOH studies. The absence of mutations in p15 gene in TGCT specimens suggests that p15 might not play an important role in the pathogenesis of testicular germ cell tumors.

Blotting, Southern

Immunohistochemical and mutational analysis of the p53 tumour suppressor gene and the bcl-2 oncogene in primary testicular germ cell tumours.

The role of p53 in testicular germ cell tumours is still contradictory based on the finding of immunohistochemical overexpression at the protein level, but lack of mutations at the DNA level. In addition, p53 wild-type activity has been demonstrated in cell culture experiments. Overexpression of the proto-oncogene bcl-2 might block p53-induced apoptosis and might inhibit p53 functional activity. To clarify the apparent paradox with respect to p53 overexpression and lack of mutations, an immunohistochemical and mutational analysis of p53 and bcl-2 in TGCT was performed. Ten normal testes, 52 CIS and 151 clinical stage I nonseminomatous GCTs were included in our study. A commercially available anti-p53 polyclonal rabbit antibody and an anti-bcl-2-mouse monoclonal antibody were used to stain the 5pm sections. Staining was assessed by counting at least 500 cells from the area of the most intense staining in each tumour cell type, and this was scored semiquantitatively for intensity of staining on a 4 point scale. In addition, 30 primary GCTs were included in the mutational analysis: areas with p53 overexpression were identified and microdissected prior to DNA extraction. p53 exons 5-8 were amplified by polymerase chain reaction (PCR) followed by single strand conformation polymorphism analysis. Templates demonstrating band shifts on SSCP were subjected to direct DNA sequence analysis. None of the normal testes, 32/52 (62%) CIS, and 142/151 (94%) germ cell tumours exhibited p53 overexpression. p53 expression was significantly lower in mature teratomas (0.8 +/- 0.2) than in other germ cell tumour components (2.8 +/- 1.2, p > 0.001). PCR-SSCP did not reveal any missense mutations or deletions for the p53 gene. Bcl-2 protein expression was observed in none of the normal testes, in none of the CIS, and in 14/151 (9.3%) germ cell tumours. 13/14 germ cell tumours demonstrated bcl-2 expression only in the glandular and stromal elements of their teratomatous components whereas all other components were negative for bcl-2. Our results--p53 overexpression, lack of p53 mutations, undetectable bcl-2--are consistent with recent in vitro studies. High susceptibility of testicular cancer to drug-induced apoptosis appears to be the result of wild-type p53 and lack of bcl-2. Radiation and chemotherapeutic insensitivity of mature teratomas might be the result of bcl-2 overexpression and lack of p53 overexpression. Therefore, chemoresistance to DNA damaging agents might be reflected by the expression of p53 and bcl-2 and it might be useful to evaluate p53 and bcl-2 in primary tumours and metastatic lesions in order to identify patients early with primary or secondary chemoresistance.

Animals

Biostatistical modeling using traditional preoperative and pathological prognostic variables in the selection of men at high risk for disease recurrence after radical prostatectomy for prostate cancer.

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.

Aged

The contemporary value of pretreatment prostatic acid phosphatase to predict pathological stage and recurrence in radical prostatectomy cases.

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.

Acid Phosphatase

Applications of neural networks in urologic oncology.

Artificial neural networks are computer-based statistical models that can be used to imitate biologic neural processes. They have been applied to a variety of problems in medicine, including diagnosis and outcomes predictions. In the area of urologic oncology, these neural networks have been used to assist in the diagnosis of prostate cancer, predicting response to therapy and recurrence in prostate cancer, predicting the presence of renal cell carcinoma in cystic renal lesions, and predicting the presence of occult metastatic disease in nonseminomatous testicular germ cell tumors. This article reviews the basic concepts of artificial neural networks and summarizes their application in urologic oncology. Neural network technology remains in its infancy in urologic oncology, and many more retrospective and prospective studies are needed to determine its clinical utility.

Computer Simulation

Contemporary hormonal management of advanced prostate cancer.

The traditional definition of "advanced" prostate cancer includes only patients with widespread osteoblastic or soft-tissue metastases (clinical or pathologic stage T any N any M1; or stage D2). Current evidence indicates that this definition should be broadened. Because many patients with T3 disease or local lymph node metastases progress to distant metastases, the concept of advanced prostate cancer should also include stages C and D1 (T3, T4, and any T N1). Furthermore, based on pretreatment prostate-specific antigen (PSA) levels, many men treated for clinically localized disease will progress rapidly and, depending on their age and general health, should be included in the advanced-disease category. Also, using prognostic marker modeling with PSA, tumor grade, and other factors, recurrences can be predicted even earlier in many cases. This may be particularly significant in light of recent clinical data indicating that early androgen ablation therapy delays disease progression and improves survival in patients with advanced (M0 or M1) disease. The luteinizing hormone-releasing hormone (LHRH) agonists have become the preferred method of androgen ablation in patients with advanced prostate cancer. Use of an LHRH agonist, alone or combined with an antiandrogen, is more acceptable to many patients than orchiectomy and lacks the potential cardiotoxicity associated with estrogens. Combined hormonal therapy remains controversial but may provide a modest survival benefit, especially in men with minimal metastatic disease. Intermittent hormonal therapy has great appeal, particularly because of the potentially deleterious effects of long-term hormonal therapy; however, its efficacy has yet to be proven.

Antineoplastic Agents, Hormonal

CD34 immunohistochemical assessment of angiogenesis as a prognostic marker for prostate cancer recurrence after radical prostatectomy.

PURPOSE: We assess the neovascularity of clinically localized prostate cancer by immunohistochemistry using the monoclonal antibody CD34 in an attempt to identify associations between angiogenesis and disease progression following radical prostatectomy. MATERIALS AND METHODS: Microvascularity was evaluated using the CD34 monoclonal antibody in archival paraffin embedded radical prostatectomy specimens from 149 patients followed from 3 to 10 years (mean 6.6). Vessels were quantified by counting a minimum of 2 selected microscopic fields (200x, 0.754 mm.2) from each tumor, area of prostatic intraepithelial neoplasia and prostatic hyperplasia, and given a numerical value representing the microvessel density count. RESULTS: Mean microvessel density count did not vary significantly with age or race. There was a significant association between the count and nuclear grade, Gleason sum and pathological stage. Cox survival analysis shows that microvessel density is significantly related to time to recurrence when considered as a continuous variable (p=0.03) as well as dichotomous variable (p=0.007) (microvessel density count less than 90 and 90 or greater). The 5-year recurrence-free survival was significantly higher for patients with a count less than 90 (71%) than for those with a count 90 or greater (51%) (p=0.006). The 5-year recurrence-free survival was also significantly different when microvessel density was used as a continuous variable (p=0.02). Controlling for stage, Gleason sum, race and nuclear grade, microvessel density remained significant in predicting recurrence (p=0.03) but when pretreatment prostate specific antigen was included in the model the count was no longer significant. The microvessel density count in the tumor area significantly increased with increasing Gleason sum and nuclear grade but it did not increase significantly in the adjacent benign prostate or areas of prostatic intraepithelial neoplasia in the same specimen. CONCLUSIONS: Microvascularity or neovascularity as measured by the CD34 antigen may be a prognostic marker of recurrence for prostate cancer patients after radical prostatectomy but more study in prostate specific antigen era patients with sufficient followup is needed.

Age Factors