Urethral anastomotic healing after radical retropubic prostatectomy: impact of positive urethral margin

OBJECTIVES

To determine the time course of urethral anastomotic healing after radical retropubic prostatectomy and its relationship to a positive margin at the anastomosis, the type of suture used, and the incidence of bladder neck contracture.

METHODS

In 119 consecutive patients a pericatheterogram was performed at 15.5 +/- 0.5 days postoperatively. A second pericatheterogram was obtained at 22.3 +/- 0.7 days for those anastomoses that were not healed, and a third pericatheterogram at 32.1 +/- 2.5 days for the remainder. Maxon sutures were used for 63 anastomoses, Dexon for 14, and chromic catgut for 42.

RESULTS

Sixty-five anastomoses (55%) were healed at the first pericatheterogram and 104 (87%) by 22 days. Microscopic tumor at the apical cut end of the prostate was found in 20% of specimens; the healing period for these patients was 21.0 +/- 2.0 days compared with 21.1 +/- 0.8 days for those with a negative margin. The healing time for Maxon, Dexon, and chromic catgut was 21.6, 24.6, and 19.5 days, respectively. Of the 108 evaluable patients, in 10 (9.3%) significant bladder neck contracture developed at a mean of 15 weeks; 6 (10.7%) were associated with Maxon anastomoses, 1 with Dexon (8.3%), and 3 (7.5%) with chromic sutures. Five of 10 bladder neck contractures were in 11 patients with previous prostate surgery (45%).

CONCLUSIONS

The presence of microscopic tumor at the urethral margin did not increase the risk of extravasation. There was no correlation between extravasation and bladder neck contracture, but less extravasation was associated with chromic sutures. Previous transurethral resection appeared to be a risk factor for the development of bladder neck contracture.

Pharmacotherapy for benign prostatic hyperplasia

Benign prostatic hyperplasia is a benign neoplasm of the prostate seen in men of advancing age. Microscopic evidence of the disorder is seen in about 70% of men by 70 years of age, whereas symptoms requiring some form of surgical intervention occur in 30% of men during their lifetime. Although the exact cause of benign prostatic hyperplasia is not clear, it is well recognized that high levels of intraprostatic androgens are required for the maintenance of prostatic growth. In recent years, extensive surveys of patients undergoing transurethral resection of the prostate reveal an 18% incidence of morbidity that has essentially not changed in the past 30 years. This procedure is also the second highest reimbursed surgical therapy under Medicare. These findings have resulted in an intensive search for alternative therapies for prostatic hyperplasia. An alternative that has now been well defined is the use of alpha-adrenergic blockers to relax the prostatic urethra. This is based on findings that a major component of benign prostatic hyperplasia symptoms is spasm of the prostatic urethra and bladder neck, which is mediated by the alpha-adrenergic nerves. A second approach is to block androgens involved in maintaining prostate growth. Several such drugs are now available for clinical use, and we discuss their side effects and use. We also include the newer recommendations on evaluating benign prostatic hyperplasia that are cost-effective yet comprehensive.

Inhibition of tumorigenic potential and prostate-specific antigen expression in LNCaP human prostate cancer cell line by 13-cis-retinoic acid

Prostate-specific antigen (PSA) is a member of the kallikrein family and has been an important biological marker for prostate cancer. The mechanisms regulating PSA expression in prostatic cancer cells are unclear. The present study was designed to elucidate the role of 13-cis-retinoic acid (RA) in regulation of PSA and the tumorigenic potential of the human prostate cancer cell line LNCaP. The growth regulation of LNCaP cells was examined by DNA synthesis and doubling time. The tumorigenic potential of prostate cancer cells was analyzed by soft agar colony-forming assay, in vitro invasion assay, type IV collagenase assay and binding to extracellular matrix assay. The nuclear receptors for retinoic acid (RAR alpha, -beta, -gamma and RXR alpha, -beta, -gamma) as well as PSA mRNA were determined by Northern blot using specific oligonucleotide probes. Our results suggest that 13-cis-RA significantly inhibits PSA secretion and expression both at the mRNA and protein levels compared with untreated cells. Electron microscopic studies suggest that after 13-cis-RA treatment, cells become more differentiated as they contain lumina, lined by plasma membrane and microvilli. Prostate cancer cell growth and tumorigenic potential after 13-cis-RA treatment was significantly decreased compared with controls. Nude mice tumorigenicity studies showed that 13-cis-RA-treated cells produced significantly smaller tumors compared with untreated cell tumors. There was also a significant increase in the expression of RXRa mRNA after 13-cis-RA treatment compared with untreated cells.

Utility of preoperative serum prostate-specific antigen concentration and biopsy Gleason score in predicting risk of pelvic lymph node metastases in prostate cancer

OBJECTIVES

To determine the accuracy of the preoperative serum concentration of prostate-specific antigen (PSA) plus the Gleason pathology score of biopsy specimens in predicting the presence of disease in the pelvic lymph nodes in patients with prostate cancer.

METHODS

The medical records of all patients treated for prostate cancer at eight medical centers from January 1988 to June 1993 were reviewed. There were 932 patients with newly diagnosed prostate cancer for whom all relevant data were available who had undergone pelvic lymphadenectomy with (n = 912) or without (n = 20) radical prostatectomy. The rate of false-negative predictions of metastases based on combined preoperative biopsy Gleason score and serum PSA concentration was analyzed. A multivariate logistic regression analysis was performed to assess the value of preoperative serum PSA and biopsy Gleason scores individually and in combination in predicting pelvic lymph node metastases.

RESULTS

The false-negative rate of metastases was 0% for preoperative PSA concentrations < or = 6 ng/mL and biopsy Gleason scores < or = 5 (n = 142) and 1.0% for PSA concentrations < or = 10 ng/mL and Gleason scores < or = 6 (n = 388). The 95% upper confidence limit for the rate of false negativity at this PSA cut-off level was 2.0%. A combination of preoperative serum PSA levels and biopsy Gleason scores provided the best prediction for the false-negative rates.

CONCLUSIONS

For patients with newly diagnosed prostate cancer who have biopsy Gleason scores < or = 6 and preoperative PSA concentrations < or = 10 ng/mL (42% of our series), a staging pelvic lymphadenectomy appears to be unnecessary. The substantial cost associated with both cross-sectional imaging and staging lymphadenectomy may therefore be avoidable in this group of patients.

Indications for and the significance of seminal vesicle irradiation during 3D conformal radiotherapy for localized prostate cancer

PURPOSE

To evaluate the use of pretreatment prostate specific antigen, Gleason score, and clinical stage as predictors of the risk of seminal vesicle involvement in patients with clinically localized prostatic cancer, and to determine the impact of excluding the seminal vesicles on the dose received by surrounding normal tissues.

METHODS AND MATERIALS

An empirically derived equation combining the preoperative prostate specific antigen and Gleason score was applied to 188 patients treated with radical prostatectomy, for whom pathologic evaluation of the seminal vesicles was available. High and low risk groups for seminal vesicle involvement were defined using this equation. The observed risks of seminal vesicle involvement was compared to the predicted risk using the preoperative prostate specific antigen, Gleason score or clinical stage alone or using the empirical equation. Dose-volume histograms for five patients treated using six-field conformal radiotherapy were compared including and excluding the seminal vesicles.

RESULTS

Using the empirically derived equation, a low risk group of 109 patients was identified with a calculated risk of seminal vesicle involvement of < or = 13% and an observed incidence of 7.3%. Among the high risk group of 79 patients, which included all patients with a calculated risk > 13%, 37% had seminal vesicle involvement (p < 0.001 low vs. high risk). Twenty percent of the rectal volume received on average above 86% of the total dose for the five plans which included the seminal vesicles compared to 68% for the five plans excluding the seminal vesicles. The doses to 40% of the rectal volume were 64% and 37% if the seminal vesicles were included and excluded, respectively. The dose to the bladder and femoral heads was also decreased but to a lesser extent.

CONCLUSION

The empirical formula predicts risk of seminal vesicle involvement with a higher degree of significance for a larger number of patients than either Gleason score, clinical stage, or prostate specific antigen alone. Based on an analysis of our first 100 patients treated with definitive conformal therapy alone, approximately 47% of those patients could have been treated excluding the seminal vesicles. Excluding the seminal vesicles may allow us to go to a higher total dose with less rectal toxicity.

Comparison of prostate specific antigen with prostate specific antigen density for 3 clinical applications

We compared prostate specific antigen (PSA) to PSA density for 3 clinical uses: detection of nonpalpable prostate cancer, staging of clinically localized prostate cancer and prediction of PSA detectability following radical prostatectomy. Of 153 men with normal digital rectal examinations undergoing prostate biopsy 25% had prostate cancer. Analysis of receiver operator characteristic curves demonstrated that PSA density predicted the outcome of biopsy significantly better than did PSA (p = 0.0013). Pathological examination of 155 radical prostatectomy specimens revealed that 56% had pathologically uncontained disease. There was no difference between the ability of PSA and PSA density to predict the pathological findings (p = 0.2379). PSA data more than 1 year postoperatively were available in 96 of the 155 prostatectomy patients. Of these men 41% had postoperative PSA levels of 0.1 ng/ml. or more. Preoperative PSA and PSA density values were almost identical in the ability to identify these patients (p = 0.6776). While PSA density is superior to PSA for the detection of prostate cancer in patients with a palpably normal prostate, it does not offer any improvement over PSA for staging of prostate cancer or for the prediction of PSA detectability after radical prostatectomy.

Characterization and partial purification of mRNA N6-adenosine methyltransferase from HeLa cell nuclei. Internal mRNA methylation requires a multisubunit complex

N6-Methyladenosine is found at internal positions of mRNA in higher eukaryotes. This post-transcriptional modification occurs at a frequency of one to three methylation/average mRNA molecule in mammalian cell lines and is sequence-specific. A highly conserved consensus recognition site for the methyltransferase has been determined from both viral and cellular messages, consisting of the sequence Pu(G/A)AC(U/A) (with A being methylated). Despite the ubiquity and the specificity of this modification, little is known about the mechanism of formation of N6-methyladenosine. Utilizing an in vitro methylation system from HeLa cell nuclear extracts, and a substrate RNA derived from the mRNA coding for bovine prolactin, the mRNA N6-adenosine methyltransferase has been characterized and partially purified. Unique among other characterized nucleic acid methyltransferases, the enzyme is composed of three components which are separable under non-denaturing conditions. The molecular masses of the components are 30, 200, and 875 kDa as determined by gel filtration and glycerol gradient sedimentation. The 200-kDa component appears to contain the S-adenosylmethionine-binding site on a 70-kDa subunit. The 875-kDa component has affinity for single-stranded DNA-agarose, suggesting that it may contain the mRNA-binding site. N6-Adenosine methyltransferase is not sensitive to treatment with micrococcal nuclease, nor to immunodepletion using an anti-trimethylguanosine antibody, suggesting that it does not contain an essential RNA component.

Transurethral evaporation of prostate (TUEP) with Nd:YAG laser using a contact free beam technique: results in 61 patients with benign prostatic hyperplasia

OBJECTIVE

This prospective study was undertaken to evaluate the safety and efficacy of neodymium:yttrium-aluminium-garnet (Nd:YAG) laser for treatment of symptomatic benign prostatic hyperplasia (BPH).

METHODS

A total of 61 patients at a mean age of 71.6 years with symptomatic bladder outlet obstruction due to BPH underwent transurethral evaporation of prostate (TUEP) using Nd:YAG laser. Twelve of the patients were experiencing acute retention. Pre- and postoperative evaluation consisted of American Urological Association (AUA) symptom questionnaire and a sexual function questionnaire, uroflowmetry, postvoid residual urine, electrolytes, blood urea nitrogen, creatinine, hematocrit, and prostate volume estimation by transrectal ultrasound. TUEP was achieved by employing a side-firing Nd:YAG laser fiber with a durable quartz reflector and high-power density (Ultraline, Heraeus LaserSonics, Milpitas, CA) that was used in a contact mode.

RESULTS

All patients have been evaluated for three months, 26 for six months, and 7 for twelve months. Mean prostatic size was 41.1 g. The mean improvement in symptom scores at one, three, six, and twelve months was 69.8 percent, 70.9 percent, 76.0 percent, and 70.9 percent, respectively (P = < 0.0001). The mean increase in maximum uroflow at one, three, six, and twelve months was 63.4 percent, 66.7 percent, 41.94 percent, and 164.52 percent, respectively (P = < 0.0001). There was no instance of significant fluid absorption or bleeding. The duration of postoperative catheterization was two days in 43 patients, three to seven days in 16 patients, and two to three weeks in 2 patients. There were no deaths. All patients evaluated by TRUS at six months had open channeling defects. Videocystoscopy performed in 16 patients at two to three months postoperatively revealed tissue slough. At repeat cystoscopy in these patients at six months, the prostatic fossa was completely healed with no evidence of tissue slough.

CONCLUSIONS

It is concluded that the technique of TUEP using Nd:YAG laser is safe and, in preliminary results, appears apparently effective in the management of BPH.

Neoadjuvant hormonal therapy and radical prostatectomy for clinical stage C carcinoma of the prostate

OBJECTIVE

To determine whether hormonal therapy prior to radical prostatectomy (neoadjuvant hormonal therapy) leads to improved results in patients with stage C prostate cancer.

PATIENTS AND METHODS

Thirty patients received neoadjuvant hormonal therapy for stage C carcinoma of the prostate. Eighteen patients who responded to treatment subsequently underwent extirpative surgery.

RESULTS

Fourteen of the 30 patients (47%) were diagnosed as being downstaged to clinical stage B disease following therapy. No major complications occurred. Pathology staging revealed only three patients (10%) to have organ-confined disease after radical prostatectomy.

CONCLUSIONS

Neoadjuvant hormonal therapy prior to radical prostatectomy offers little probability of rendering patients with clinical stage C carcinoma of the prostate free of disease. Further investigation of the efficacy of this treatment should be accomplished in randomized trials.

Monitoring of body weight during transurethral resection of the prostate: preliminary report

The fear of vascular overload by irrigant during transurethral resection of the prostate is a reason for an incomplete resection. With continuous measurement of the patient's body weight and, thus, body water, irrigant entrance is immediately identified. We present a scale of proved accuracy and reliability, allowing more effective resection while eliminating the possibility of TUR syndrome.

Evidence against norepinephrine-stimulated efflux of mitochondrial Mg2+ from intact cardiac myocytes

We investigated the hypotheses that norepinephrine stimulates Mg2+ efflux from intact isolated adult rat ventricular cardiomyocytes and that adenosine 3',5'-cyclic monophosphate stimulates Mg2+ efflux from permeabilized myocytes and isolated mitochondria. Norepinephrine stimulation of Mg2+ release from cardiac myocytes was observed only when cells at approximately 20 mg protein/ml in Mg(2+)-containing buffer were diluted 50- to 60-fold into an Mg(2+)-free medium. Under these conditions, > 30% of total cellular lactic acid dehydrogenase activity was also released, indicating that a significant portion of the cells had died. In other protocols, where Mg2+ efflux from myocytes was not observed, extracellular Mg2+ removal and administration of 10 microM norepinephrine increased 45Ca2+ accumulation by cells in suspension. In single myocytes, Mg2+ removal and norepinephrine administration increased intracellular free [Ca2+] as measured by fura-2 fluorescence microscopy, and this was accompanied by vigorous spontaneous contractile activity followed by Ca2+ overload hypercontracture. With permeabilized myocytes and isolated mitochondria from a variety of sources, adenosine 3',5'-cyclic monophosphate did not stimulate Mg2+ efflux. These results suggest that recent evidence for direct hormonal regulation of myocardial Mg2+ homeostasis may need to be reevaluated.

Context effects on N6-adenosine methylation sites in prolactin mRNA

The methylation of internal adenosine residues in mRNA only occurs within GAC or AAC sequences. Although both of these sequence motifs are utilized, a general preference has been noted for the extended sequence RGACU. Not all RGACU sequences in an mRNA are methylated and the mechanisms that govern the selection of methylation sites in mRNA remain unclear. To address this problem we have examined the methylation of transcripts containing sequences of a natural mRNA, namely, bovine prolactin mRNA. In this mRNA, a specific AGACU sequence in the 3' untranslated region is the predominant site of methylation both in vivo and in vitro. The degree to which N6-adenosine methyltransferase recognizes the sequence context of the consensus methylation site was explored by mutational analysis of the nucleotides adjacent to the core sequence as well as the extended regions in which the core element was found. Our results indicate that efficient methylation depends on the extended five nucleotide consensus sequence but is strongly influenced by the context in which the consensus sequence occurs within the overall mRNA molecule. Furthermore, consensus methylation sites present in an RNA duplex are not recognized by the methyltransferase.

Management of benign prostatic hyperplasia

The Council on Scientific Affairs of the California Medical Association presents the following inventory of items of progress in urology. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established, both as to scientific fact and important clinical significance. The items are presented in simple epitome, and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, researchers, and scholars to stay abreast of these items of progress in urology that have recently achieved a substantial degree of authoritative acceptance, whether in their own field of special interest or another. The items of progress listed below were selected by the Advisory Panel to the Section on Urology of the California Medical Association, and the summaries were prepared under its direction.

Effects of diltiazem, metoprolol, enalapril and hydrochlorothiazide on frequency of ventricular premature complexes

Ventricular arrhythmias occur frequently in patients with hypertensive left ventricular (LV) hypertrophy and have been associated with increased incidence of sudden death. In this study, the effect of various antihypertensive medications on ventricular arrhythmias was evaluated in 31 hypertensive patients with moderate to severe LV hypertrophy. Patients were assessed at baseline (after 3 weeks of placebo treatment) and after treatment with each of 4 monotherapies: diltiazem 120 or 240 mg/day, metoprolol 100 or 200 mg/day, enalapril 10 or 20 mg/day and hydrochlorothiazide 50 or 100 mg/day. Each drug therapy was administered for 4 weeks. The sequence of each treatment was determined at random. Echocardiographic measurements and electrocardiograms were obtained only at baseline. Biochemical measurements and 48-hour Holter monitoring were obtained at baseline and at the end of each treatment. All treatments resulted in a significant but similar decrease in blood pressure. In the group as a whole diltiazem decreased ventricular premature complexes (VPCs) by 65% (p < 0.05) and metoprolol by 52% (p = 0.07). Enalapril and hydrochlorothiazide had no effect. In 12 patients with > or = 5 VPCs/hour at baseline, diltiazem and metoprolol decreased VPCs by 66% (p < 0.05). It is concluded that in hypertensive patients with moderate to severe LV hypertrophy, both diltiazem and metoprolol significantly reduce VPCs.

Ploidy status correlates with outcome in stage B prostate adenocarcinoma

1. While there are extensive data showing that aneuploidy is associated with adverse outcome in stage D prostate cancer, the utility of ploidy analysis in stage B disease is unclear. We determined ploidy in radical prostatectomy specimens from 28 patients with clinical stage B prostate cancer, and with a mean follow-up of 4.1 years (2-10 years). Patients who had no recurrences had a minimum 5 years of follow-up. Patients who had only 2 years of follow-up were included if they had developed bone metastases during this period. 2. Ploidy determinations were done on Feulgen-stained 5-microns paraffin-embedded sections using a CAS 200 image analyzer. At least 400 tumor cells were counted in every case. Tumors with at least 70% diploid cells were classified as diploid, while those with less than 70% diploid cells were classified as aneuploid. The mean percentage of diploid cells in tumors classified as diploid was 90.6 +/- 7.4, while the mean percentage of diploid cells in tumors classified as aneuploid was 36 +/- 21.9. 3. Ploidy status correlated with disease progression: seven of the 10 patients (70%) with disease recurrence had aneuploid tumors, while 13 of 18 patients (72%) who remained disease-free had diploid tumors (P = 0.03, Chi-square test). 4. These data show that patients with stage B disease with aneuploid tumors at the time of prostatectomy are more likely to have recurrent disease within a mean of 3 years (2-6 years) compared to patients with diploid tumors.(ABSTRACT TRUNCATED AT 250 WORDS)

Factors affecting size and configuration of neodymium:YAG (Nd:YAG) laser lesions in the prostate

Laser surgery for benign prostatic hypertrophy is a clinical reality and a promising alternative to traditional transurethral electroresection of the prostatic adenoma (TURP). Current methods of laser prostatectomy involve coagulation of prostate tissue using a quartz side-firing fiber that redirects a Nd:YAG laser beam at 70-90 degrees most commonly by means of a metal reflector. In this communication we describe a method of tissue evaporation using a side-firing fiber that avoids use of a metal reflector by means of internal reflection. It is relatively resistant to damage when coming in contact with tissue. By placing the fiber tip in direct contact with tissue, much larger lesions are created because of more efficient energy transfer resulting in rapid evaporation of tissue under water. In prostate surgery, this phenomenon of accelerated evaporation can be used to bloodlessly evaporate adenomatous tissue creating a defect that resembles that of a traditional TURP.

Role of penile vascular injury in erectile dysfunction after radical prostatectomy

OBJECTIVE

To investigate the cause of erectile dysfunction after nerve-sparing radical prostatectomy for clinically localized adenocarcinoma of the prostate (stage A or B).

PATIENTS AND METHODS

Erectile function was evaluated in 20 patients, mean age 65 years (range 44-74), both pre-operatively and 1 year after surgery by intracavernosal injection of a vasoactive agent (papaverine hydrochloride or prostaglandin E1) and pulsed Doppler ultrasonography. The degree of erection, the size of the cavernosal artery and penile arterial blood flow velocity were assessed.

RESULTS

Results revealed that the decreased response to intracavernosal injection of a vasoactive agent was associated with a significant reduction in both the diameter and velocity of blood flow within cavernosal arteries in 40% of patients after surgery. The pathological stage of the tumour did not correlate with the degree of vascular injury.

CONCLUSION

We conclude that post-prostatectomy impotence is multifactorial but vascular injury plays a substantial role.

N6-adenosine methylation in mRNA: substrate specificity and enzyme complexity

The N6-methylation of internal adenosine residues is a common post-transcriptional modification of eukaryotic pre-mRNA sequences. An in vitro methylation system which retains the precise selectivity of in vivo methylation sites has been used to further define the nature of RNA site recognition. In addition to short consensus sequences, other structural features or context effects contribute to the selection of methylation sites in pre-mRNAs. Partial purification of the mRNA N6-adenosine methyltransferase revealed unexpected levels of complexity. The methyltransferase is composed of three separate components with molecular masses of 30, 200 and 875 kDa, respectively. These components are readily separated under non-denaturing conditions and each is required for mRNA methylation activity.

Predicting the risk of lymph node involvement using the pre-treatment prostate specific antigen and Gleason score in men with clinically localized prostate cancer

PURPOSE

To evaluate the predictive value of an empirically derived equation for identifying patients with clinically localized prostate cancer at low and high risk for harboring occult lymph node metastasis.

METHODS AND MATERIALS

A simple equation for estimating the risk of positive lymph nodes was empirically derived from a nomogram published by Partin et al. demonstrating the value of combining the pre-treatment prostate specific antigen and Gleason Score in predicting the risk of lymph node metastasis for patients with clinically localized prostate cancer. The risk of positive nodes (N+) was calculated using the equation; N+ = 2/3(PSA) + (GS-6) x 10, where PSA and GS are the pre-treatment prostate specific antigen and Gleason Score respectively, and the calculated risk is constrained between 0-65% for a PSA < or = 40 ng/ml (as in the nomogram). To test the general applicability of this equation, we reviewed the pathologic features of 282 of our patients who had undergone a radical prostatectomy.

RESULTS

Based on 212 patients for whom the pre-operative prostate specific antigen's and Gleason Scores were available, we identified 145 patients with a calculated risk of positive nodes of < 15%, (low risk group) and 67 patients with a calculated risk as > or = 15% (high risk group). The observed incidence of positive nodes was 6% and 40% among the low and high risk groups respectively (p < 0.001). When used alone neither clinical stage, pre-treatment prostate specific antigen nor the pre-treatment Gleason Score was as useful in identifying the largest low and high risk groups.

CONCLUSION

Using the equation described we confirmed the general applicability of the nomogram reported by Partin et al. and identified patients at low and high risk for lymph node involvement. Based on these data we have adopted a policy of omitting whole pelvic irradiation in patients identified as low risk.

13-cis-retinoic acid-mediated growth inhibition of DU-145 human prostate cancer cells

The purpose of this study was to examine the effects of 13-cis-retinoic acid (13-cis-RA) on the growth regulation of DU-145 human prostatic cancer cells. The results of these experiments demonstrate that cell growth and metastatic potential of DU-145 cells were significantly inhibited by 13-cis-RA (10 microM). In order to elucidate the possible molecular mechanisms of 13-cis-RA action on prostate cancer cells, we examined the expression of nuclear receptor genes (hRXR alpha) and found that 13-cis-RA treated cells showed higher mRNA expression for hRXR alpha nuclear receptors compared to untreated cells. To elucidate further the possible biochemical mechanisms associated with these alterations, we analyzed the phosphorous metabolites by MR spectroscopy and found that the major metabolites were PME, (PC, PE) and DPDE (UDP-GalNAc, UDP-GLcNAc). The DU-145 cells and xenografts, which were both treated with 13-cis-RA, showed a two-fold decrease in DPDE's, compared to their controls. The higher resolution spectra of perfused cells revealed that phosphocholine levels were twice as high in 13-cis-RA-treated DU-145 cells as compared to untreated cells. These investigations demonstrate for the first time that 13-cis-RA inhibits the growth of human prostatic cancer cells, and this inhibition is associated with an increase in hRXR alpha nuclear receptor gene expression and alterations in phosphorous metabolites detected by 31P MR spectroscopy.

Selection of patients for laparoscopic pelvic lymphadenectomy prior to radical prostatectomy: a decision analysis

Indications for laparoscopic pelvic lymphadenectomy prior to radical prostatectomy have not been established. Criteria to predict lymph node metastases were derived from the preoperative evaluations of 164 prostate cancer patients undergoing pelvic lymphadenectomy. Decision analysis was used to determine which criteria would be optimal indicators for laparoscopic pelvic lymphadenectomy prior to intended radical prostatectomy. Besides a digital rectal examination suggesting uncontained tumor, which was the best indication for laparoscopic pelvic lymphadenectomy, the most useful criteria were sonographic tumor volume > or = 3 cc and prostate-specific antigen (PSA) > or = 20 ng/mL. If either parameter was met, the sensitivity for identifying patients with pelvic lymph node metastases was 88 percent and the positive predictive value was 42 percent. When both were met, the sensitivity fell to 47 percent but the positive predictive value increased to 67 percent. A combination of Gleason biopsy score and PSA was the best criterion that was independent of transrectal ultrasonography. Using a PSA > or = 15 ng/mL for tumors with Gleason biopsy score > or = 7 or a PSA > or = 25 ng/mL for tumors with a Gleason biopsy score of 5-6 had a sensitivity of 71 percent and positive predictive value of 48 percent for identifying patients with pelvic lymph node metastases. In selecting patients for laparoscopic pelvic lymphadenectomy prior to radical retropubic prostatectomy, criteria with a positive predictive value greater than 39 percent maximize the utility of laparoscopic pelvic lymphadenectomy. Prior to radical perineal prostatectomy, laparoscopic pelvic lymphadenectomy will identify pelvic lymph node metastases that would otherwise be undetected by prostatectomy alone. The sensitivity of selection criteria, therefore, should be increased, as long as the positive predictive value remains above 20 percent.

Re-evaluation of the need for pelvic lymphadenectomy in low grade prostate cancer

In a series of 166 patients undergoing radical prostatectomy and bilateral pelvic lymph node dissection for clinical stage A and B prostate cancer we found that 83% of patients with lymph node metastases had a final tumour Gleason score > or = 7. Gleason scoring of the pre-operative biopsy demonstrated 3 groups of patients with biopsy scores < or = 5, 6, and > or = 7, and a prevalence of lymph node metastases of 2, 13 and 23% respectively. The pre-operative serum prostate specific antigen (PSA) was of marginal value in predicting either the presence of lymph node metastases or the presence of cancer, since 15% of patients with nodal metastases had normal pre-operative PSA levels, as did 54% of patients with tumour Gleason scores < or = 5. It was concluded that the need for pelvic lymph node dissection in patients with low grade tumours is questionable because of the low prevalence of lymph node metastases, and that the pre-operative biopsy can identify those patients who are at low risk for lymph node metastases.

HLA expression by benign and malignant prostatic epithelium: augmentation by interferon-gamma

Chronic prostatitis is a poorly understood entity that is characterized by lymphocytic infiltration of benign prostatic epithelium. Previously, we and others have shown that prostatic epithelium involved by prostatitis is phenotypically different from uninvolved epithelium. In addition, we have shown that malignant prostatic epithelium is rarely, if ever, infiltrated by lymphocytes. We now report that benign prostatic epithelium expresses HLA-DR only in the presence of lymphocytic inflammation, and that benign epithelium without chronic prostatitis and malignant prostatic epithelium do not express HLA-DR. In order to determine whether HLA-DR expression is inducible on malignant prostatic epithelium and therefore, at least theoretically, susceptible to immune regulation, we studied the DU-145 cell line in culture under various conditions. DU-145 cells did not express HLA-DR under routine culture conditions. However, the addition of interferon-gamma (100 to 6000 U/ml.) resulted in HLA-DR expression by DU-145 cells at 24 hours with maximal expression by 72 hours. In contrast, other cytokines (tumor necrosis factor, interleukin-1, interleukin-2) had no effect on HLA-DR expression. These investigations show that interferon-gamma induces HLA-DR expression on the DU-145 prostatic adenocarcinoma cell line, raising the theoretical possibility that malignant prostatic cells may be induced in vivo to express HLA-DR and thus become susceptible to immune regulation.

The syndrome of inappropriate antidiuretic hormone secretion in a patient with adenocarcinoma of the prostate

We report the syndrome of inappropriate antidiuretic hormone secretion in a 59-year-old man with stage C adenocarcinoma of the prostate. Serum antidiuretic hormone levels returned to normal following treatment with a gonadotropin-releasing hormone analogue. To our knowledge this case represents the first in which resolution of this syndrome occurred with treatment of the carcinoma.

Combined role of transrectal ultrasonography, Gleason score, and prostate-specific antigen in predicting organ-confined prostate cancer

Prostate cancer staging is frequently inaccurate. By combining transrectal ultrasonography (TRUS) with a retrospectively derived grade-stratified prostate-specific antigen (PSA-GS) scale, we demonstrated 77 percent staging accuracy in 155 men with clinically localized prostate cancer undergoing radical prostatectomy. When used as the first step in a staging algorithm, PSA-GS (Score > or = 7: PSA > or = 4.0 ng/mL, uncontained; Score = 5 or 6: PSA > or = 8.0 ng/mL, uncontained; Score < or = 4: PSA > or = 16.0 ng/mL, uncontained) had a sensitivity of 75 percent and a specificity of 72 percent. The addition of TRUS to the staging algorithm, necessary only in patients with negative predictions by PSA-GS (46%), increased the sensitivity to 86 percent and the negative predictive value to 79 percent, while positive predictive value was unchanged at 77 percent. The combination of TRUS with PSA < 4 ng/mL or > or = 16 ng/mL identified subsets of patients with 85 percent and 88 percent likelihood of contained and uncontained disease, respectively. Our algorithm minimizes operator dependency by requiring TRUS in less than half of the patients. It produced improved staging, but the overall results were inaccurate in 23 percent of patients. Further refinements in prostate cancer staging are still necessary.

Phenotypic and cytogenetic characterization of a human corpus cavernosum cell line (DS-1)

We report here the establishment and characterization of a corpus cavernosum cell line (DS-1) from human penile tissue. This is the first cell line of its type derived from cavernosum tissue. DS-1 cells have become immortalized in culture, and show growth in monolayers. These cells have a doubling time of about 45 h in in vitro culture. Cytogenetic analysis by G-banding demonstrated a diploid karyotype with a model chromosome number of 46. The chromosome constitution of DS-1 cells was found to be male (XY), in 28/30 cells scored. Two of the 30 cells showed an extra structurally rearranged "marker" chromosome, that appeared to be a derivative of chromosome 18 with excessive chromosome on the short arm. Ploidy analysis revealed that the majority of DS-1 cells had a DNA index of one. About 35% cells were found to be in G-1 phase and 52% cells in S phase. Light and electron microscopy of DS-1 cells and original penile tissue showed typical characteristics of this tissue. Immunocytochemistry studies using antibodies to smooth muscle actin, desmin, vimentin and cytokeratin (LP34, CAM5.2) showed that the DS-1 cell line had predominantly smooth muscle cells, as these cells were positive for smooth muscle actin, desmin and vimentin.

Treatment of prostatic bleeding: suppression of angiogenesis by androgen deprivation

Bleeding of prostatic origin is usually caused by the friable hypervascularity of the aging prostate. Suppression of angiogenesis can be achieved through any hormonal manipulation that causes androgen deprivation. We present 4 cases of severe recurrent hematuria treated successfully by this approach.

The value of prostate specific antigen and transrectal ultrasound guided biopsy in detecting prostatic fossa recurrences following radical prostatectomy

The combination of prostate specific antigen (PSA) and transrectal ultrasonography was used to detect recurrent cancer in the prostatic fossa after radical prostatectomy. A total of 43 patients with persistently elevated PSA levels and negative bone scintigraphy following radical prostatectomy underwent digital rectal examination and transrectal ultrasonography. Ultrasound findings were considered suspicious if the scan showed any unusual hypoechoic tissue adjacent to the bladder neck, retro-trigone or peri-anastomotic site. Of 22 patients (51%) with biopsy proved cancer 21 (95%) had positive transrectal ultrasonography, while digital rectal examination was able to detect cancer in only 10 (45%). Among transrectal ultrasonography detected recurrences 15 (68%) were detected at the initial biopsy and 7 (32%) at repeat biopsies. Our study shows that the combination of PSA and transrectal ultrasonography provides a more effective method than digital rectal examination and PSA to detect biopsy proved cancer following radical prostatectomy.

Effect of glucose and confluency on phosphorus metabolites of perfused human prostatic adenocarcinoma cells as determined by 31P MRS

A series of perfused cell 31P MRS studies were conducted using a well established human prostate adenocarcinoma cell line (DU 145) at different phases of growth, and exposed to varying glucose concentrations during growth. The spectral characteristics of perfused DU 145 cells were compared with the same cells grown in nude mice (xenografts). Perfused DU 145 cells had lower levels of inorganic phosphate and phosphocreative relative to in vivo nude mice xenografts. 31P MR spectra obtained from perfused cells at different phases of growth and exposed to varying glucose concentrations during grown suggest that increases in diphosphodiester levels are associated with high glucose concentrations and confluency. Perfused DU 145 cells grown in 5.5 mM glucose and harvested at log phase of growth best reflected the phosphorus MR spectra of the same cell line grown in nude mice.

Citrate alterations in primary and metastatic human prostatic adenocarcinomas: 1H magnetic resonance spectroscopy and biochemical study

The objectives of this study were to quantitatively verify the low levels of citrate previously observed in primary human prostatic adenocarcinomas and to determine whether citrate was further reduced in metastatic prostatic cancer. This was accomplished by comparison of citrate concentrations of DU 145 xenografts (a poorly differentiated human prostatic adenocarcinoma cell line grown in nude mice) with concentrations in primary human adenocarcinomas. Following in vivo 1H NMR studies of DU 145 xenografts, citrate concentrations of DU 145 xenografts and surgically removed primary prostatic adenocarcinoma tissue were determined by quantitative high resolution 1H NMR and enzymatic assay. The most significant findings of this study were that citrate concentrations in primary human adenocarcinomas (3.74 +/- 0.19 mumol/g wet weight) were significantly lower than those observed for normal and benign hyperplastic (BPH) prostatic tissues. Furthermore there was a further ten-fold reduction of citrate associated with DU 145 xenografts (0.31 +/- 0.028 mumole/g wet weight) compared with primary prostatic cancer. DU 145 xenografts also exhibited higher levels of uridine diphosphosugars and choline containing metabolites relative to primary prostatic adenocarcinomas. These findings support the hypothesis that citrate is low in primary prostatic cancer and further reduced in metastatic disease.

Cell proliferation in prostatic adenocarcinoma: in vitro measurement by 5-bromodeoxyuridine incorporation and proliferating cell nuclear antigen expression

We assessed cancer cell proliferation, a marker of the biologic activity of tumor cells, by evaluating bromodeoxyuridine (BrdUrd) incorporation and proliferating cell nuclear antigen (PCNA) expression. Prostatic carcinoma specimens (N = 48) were incubated in the presence of BrdUrd to label cells undergoing DNA synthesis, and immunocytochemical staining was performed with monoclonal antibodies to BrdUrd and PCNA and a standard indirect immunoperoxidase technique. The proportion of cells staining positively (labeling index or LI) for BrdUrd and PCNA was determined in 2 ways: by counting only high-power fields with the greatest concentration of stained cells (selected LI); or by counting cells in random fields (random LI). For BrdUrd the mean selected and random LIs were 3.08% and 1.62%, respectively; for PCNA they were 6.02% and 3.47%. Random and selected BrdUrd correlated well (r2 = 0.83), as did random and selected PCNA LIs (r2 = 0.86). However, a weaker correlation was noted when LIs of both techniques were compared, with the PCNA LI usually higher. The LIs of either technique correlated rather poorly with tumor grade and concentration of prostate-specific antigen, but correlated well with clinical stage as assessed by examination and imaging. In addition, either technique discriminated among tumors known to be pathologically confined (stages A and B) and those with extension to seminal vesicles (stage C) or metastatic to regional lymph nodes or bone (p < 0.019).

Sodium nitroprusside and neurostimulation cause increased levels of cyclic guanosine monophosphate and not cyclic adenosine monophosphate during canine penile erection

We investigated the changes of cGMP and cAMP during penile erection induced by direct electrical stimulation of the pelvic nerve or sodium nitroprusside administration. Immediately after penile erection, the samples were put into liquid nitrogen and cyclic nucleotide content was measured. The results of these investigation suggest that both pelvic nerve stimulation and sodium nitroprusside induced penile tumescence. The total content of cGMP and not cAMP were significantly higher in treated samples as compared to control. SDS-polyacrylamide gel electrophoresis revealed several differences after treatment compared to untreated samples. This study demonstrated that the total content of cGMP and not cAMP increased after pelvic nerve stimulation and sodium nitroprusside treatment in penile tissue.

Downregulation of saturated fatty acid and upregulation of unsaturated fatty acid by 13-cis-retinoic acid in human prostate cancer cells

Retinoids play a major role in regulation of epithelial cell growth and cellular differentiation, but their mechanism(s) of action are still unclear. In the present study, we examined the effects of 13-cis-retinoic acid (13-cis-RA) on cytotoxicity, growth properties, morphology, neutral lipids, phospholipids and fatty acids in cultured human prostate cancer cell lines. The results of these experiments suggest that 13-cis-RA (10 microM) inhibits the DNA synthesis and nude mice tumorigenicity by 2- to 3-fold, compared to control. Electron microscopy revealed more differentiated phenotypes after 13-cis-RA treatment. There was a significant increase in phosphatidylcholine and decrease in sphingomyelin in 13-cis-RA treated cells compared to control. The saturated fatty acids significantly decreased whereas unsaturated fatty acids were increased after 13-cis-RA treatment in prostate cancer cells. This study demonstrates for the first time that retinoic acid mediated downregulation of saturated fatty acids and upregulation of unsaturated fatty acid in human prostate cancer cells.

A randomized, placebo-controlled multicenter study of the efficacy and safety of terazosin in the treatment of benign prostatic hyperplasia

The clinical manifestations of benign prostatic hyperplasia (BPH) are related primarily to bladder outlet obstruction resulting from enlargement of the prostate gland. Transurethral prostatectomy is the most common treatment currently offered for BPH in the United States. The primary objective of the present randomized placebo controlled multicenter study was to determine the efficacy and safety of terazosin, a selective long-acting alpha 1-blocker, for the treatment of symptomatic BPH. A total of 285 men with symptomatic BPH was randomly assigned in equal proportions to receive placebo, or 2, 5 or 10 mg. terazosin administered once daily. Of the patients 237 completed the 4-week single-blind placebo lead-in and 12-week double-blind treatment periods. The primary outcome parameters were changes in peak and mean urinary flow rates, and changes in the Boyarsky symptom scores. All terazosin treatment groups exhibited significantly greater decreases in total Boyarsky symptom score than the placebo group. The 10 mg. terazosin group exhibited significantly greater increases in peak and mean urinary flow rates than the placebo group. The improvements in symptom scores and urinary flow rates did not reach a plateau within the dose range evaluated, suggesting that further efficacy may be achieved with doses of terazosin exceeding 10 mg. This study unequivocally demonstrates the safety and efficacy of terazosin for the treatment of BPH. Selective alpha 1-blockade is likely to gain widespread acceptance for the treatment of BPH due to its safety and efficacy.

Establishment and characterization of a human primary prostatic adenocarcinoma cell line (ND-1)

A human primary prostatic adenocarcinoma cell line named ND-1 has been established in long term tissue culture. The cultured cells show growth in both monolayers and in soft agar suspension and produce subcutaneous tumors in nude mice. Cytogenetic analysis by G-banding demonstrated an aneuploid karyotype with a modal chromosome number of 62, and multiple marker chromosomes with 25-30% structural abnormalities. Ploidy analysis revealed that the majority of ND-1 cells (67%) had a DNA mass of 10.1 picogram and DNA index of 1.41. Nineteen percent of cells had a DNA mass of 21.3 picogram and DNA index of 3.0. Electron microscopic studies revealed common features of neoplastic epithelial cells such as numerous microvilli, junctional complexes, abnormal nuclei, nucleoli, and mitochondria. Due to the absence of a structurally normal Y chromosome, confirmation of the presence of a derived Y chromosome was achieved through the use of C-banding and through fluorescent in situ hybridization with a Y chromosome repeat probe. Tandem E PSA immunoenzymatic assay revealed that these ND-1 cells secrete small amounts of prostate specific antigen.

Staging of prostate cancer. Accuracy of transrectal ultrasound enhanced by prostate-specific antigen

Transrectal ultrasound (TRUS) has shown some promise in the staging of prostate cancer, while prostate-specific antigen (PSA) alone is insufficient. By combining prospective TRUS evaluation with retrospective PSA analysis, we demonstrated an increased accuracy of this combined staging method over TRUS alone. In 48 men undergoing radical prostatectomy, TRUS was performed and PSA measured pre-operatively. On the basis of TRUS, tumours were classified as contained or uncontained. An "expected" PSA value was then calculated for each patient as follows: K x volume of hypoechoic area +0.07 x prostate volume where K = 2.1 if the combined Gleason score of the initial biopsy was > or = 7, or 4.2 if the score was < or = 6. If a patient's pre-operative PSA value was less than or equal to the expected PSA, his tumour was judged to be contained. Staging by both TRUS and PSA was combined, so that if the tumour was judged uncontained by either parameter, the combined prediction was uncontained. Results of the combined staging were: sensitivity 84%, specificity 82%, positive predictive value 94%, negative predictive value 60%, accuracy 83%. This PSA formula, which takes into account the size and grade of the lesion rather than an arbitrary cut-off value, enhances the local staging of prostate cancer by TRUS.

Incidental lymphocytic prostatitis. Selective involvement with nonmalignant glands

We documented the presence of lymphocytic prostatitis in all prostate specimens received over a 4-month period. Lymphocytic prostatitis was present in 44% of biopsy specimens (n = 77), 95% of transurethral prostatic resection specimens (n = 20), and 100% of total prostatectomy specimens (n = 9). The patchiness of the prostatitis within the prostate in part explains the lower prevalence in the biopsy specimens, which sample a much smaller portion of the gland compared with the other procedures. Lymphocytic prostatitis was seen in prostates both with and without adenocarcinoma. However, in specimens containing carcinoma, the lymphocytic aggregates rarely involved malignant glands. Instead, the aggregates were either stromal or involved nonmalignant glands either adjacent to or away from the tumor, including glands with hyperplasia, atrophy, and prostatic intraepithelial neoplasia. Even when malignant and nonmalignant glands were in close proximity, there was a sharp demarcation with respect to lymphocytic inflammation. Immunohistochemical staining with B-cell and T-cell markers disclosed that the vast majority are T lymphocytes. The localization of lymphoid aggregates to nonmalignant (including prostatic intraepithelial neoplasia) glands but not frankly neoplastic glands, suggests a selective escape of immune detection by neoplastic glands.

Biochemical, cytogenetic, and morphological characteristics of human primary and metastatic prostate cancer cell lines

Metastatic properties of human prostatic cancer cell lines (ND-1 and DU-145) were examined using various biochemical techniques. DU-145 cells had a higher metastatic potential than ND-1 cells. Cytogenetic analysis by G-banding demonstrated an aneuploid karyotype with considerable structural rearrangement. ND-1 cells had a modal chromosome number range lower than DU-145 cells (45-66, compared to 54-62). Ploidy analysis revealed that DU-145 cells showed hyperdiploidy with a greater amount of proliferation than the majority of ND-1 cells. Electron microscopic studies revealed little change in the cell morphology of either line. DU-145 cells had lower phosphatidyl choline levels and higher sphingomyelin levels than ND-1. DU-145 cells had much lower arachidonic acid levels than ND-1 cells. SDS-polyacrylamide gel electrophoresis revealed protein differences between the two cell lines. This study demonstrates for the first time that lipids, proteins and cytogenetic parameters differ in human primary and secondary prostate cancer cell lines.

Metastasis-associated alterations in phospholipids and fatty acids of human prostatic adenocarcinoma cell lines

Metastatic variants of human prostatic adenocarcinoma cell lines (DU-145, LNCaP, and ND-1) were studied by using soft agar colony forming efficiency, nude mice tumorigenicity, in vitro invasion assay, and type IV collagenase assay. The DU-145 and ND-1 cell line showed higher metastatic potential than LNCaP. Lipids from DU-145, ND-1, and LNCaP cells were extracted and analyzed by thin-layer chromatography and gas-liquid chromatography. The major lipids were phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, fatty acids, and cholesterol. The sphingomyelin level was significantly higher in highly metastatic cells (DU-145 and ND-1) compared with the lower metastatic variant (LNCaP). The increase in the synthetic pathway and decrease in degradation pathway of sphingomyelin in microsomal fractions was sufficient to account for the measured increase in sphingomyelin in DU-145 cells compared with LNCaP cells. The major fatty acids of these lipids were palmitic (16:0), stearic (18:0), oelic (18:1), and arachidonic acid (20:4). The arachidonic acid level was significantly decreased in DU-145 and ND-1 compared with LNCaP cells. Electron microscopic studies showed no significant changes in the morphology of DU-145, ND-1, and LNCaP cells. The results of these investigations demonstrate for the first time that sphingomyelin and arachidonic acid contents are different in high and low metastatic variants of human prostatic adenocarcinoma cell lines.

Surgical treatment of female urethral carcinoma

Urethral cancer is the only genitourinary neoplasm with a predilection for women, the ratio being 4:1. The histologic type depends on the cells of origin. Squamous-cell carcinoma predominates, with adenocarcinoma and transitional-cell carcinoma being less common and undifferentiated carcinoma, malignant melanoma, mixed tumors, clear-cell carcinoma, and cloacogenic carcinoma accounting for the remaining lesions. The authors describe the various options for the management of low-stage and high-stage cancers and of cancers arising in urethral diverticula.

Prospective randomized trial of warfarin and intermittent pneumatic leg compression as prophylaxis for postoperative deep venous thrombosis in major urological surgery

Postoperative deep venous thrombosis and pulmonary embolus remain a major source of morbidity and mortality for the urological surgery patient. We report the results of the first 100 patients in a prospective, randomized trial of low dose warfarin and intermittent pneumatic leg compression for deep venous thrombosis prophylaxis. All patients underwent preoperative and postoperative real-time ultrasound imaging and Doppler flow studies of the popliteal, femoral and iliac veins for the evaluation of deep venous thrombosis. Our results indicate that low dose warfarin is as effective as intermittent pneumatic leg compression for prophylaxis of deep venous thrombosis. Low dose warfarin can be used effectively without any significant bleeding complications. We recommend the use of low dose warfarin as an alternative to intermittent pneumatic leg compression for deep venous thrombosis prophylaxis of the urological patient undergoing a major urological operation.

Magnetic resonance spectroscopy in prostate disease: diagnostic possibilities and future developments

Magnetic resonance spectroscopy (MRS) is a relatively new technique for studying membrane and intracellular metabolic events occurring in cancer. A series of transrectal probes were used for performing MRS and subsequently for integrated MRS/magnetic resonance imaging (MRI) of the prostate. Studies using transrectal 31P/1H MRS showed that it can characterize metabolic differences between normal and malignant prostates. Specifically, malignant prostates are characterized by low levels of phosphocreatine and citrate and high levels of phosphomonoesters relative to normal glands. These findings were verified in biochemical studies of prostate biopsies. The images obtained by transrectal coil techniques were superior to images obtained by the conventional body coil technique. In the future, the integration of 1H imaging and multi-volume localization techniques (spectroscopic imaging) will allow the acquisition of metabolic maps of the prostate which may eventually be useful in diagnosis and in management of patients with prostate cancer.

31P spectroscopy of the human prostate gland in vivo using a transrectal probe

Using a transrectal probe, good quality 31P magnetic resonance spectroscopy of the human prostate was performed safely, consistently, and in a reasonable amount of time (average of 60 min). Initial results indicate that transrectal 31P MRS has the ability to characterize the phosphorylated metabolites of normal, hyperplastic, and malignant prostates. This study demonstrated that malignant prostates are characterized by significantly decreased levels of phosphocreatine (PCr) and increased levels of phosphomonoesters (PME) as compared to healthy prostates.

Characterization of prostate cancer, benign prostatic hyperplasia and normal prostates using transrectal 31phosphorus magnetic resonance spectroscopy: a preliminary report

We assessed the ability of 31phosphorus (31P) transrectal magnetic resonance spectroscopy to characterize normal human prostates as well as prostates with benign and malignant neoplasms. With a transrectal probe that we devised for surface coil spectroscopy we studied 15 individuals with normal (5), benign hyperplastic (4) and malignant (6) prostates. Digital rectal examination, transrectal ultrasonography and magnetic resonance imaging were used to aid in accurate positioning of the transrectal probe against the region of interest within the prostate. The major findings of the in vivo studies were that normal prostates had phosphocreatine-to-adenosine triphosphate (ATP) ratios of 1.2 +/- 0.2, phosphomonoester-to-beta-ATP ratios of 1.1 +/- 0.1 and phosphomonoester-to-phosphocreatine ratios of 0.9 +/- 0.1. Malignant prostates had phosphocreatine-to-beta-ATP ratios that were lower (0.7 +/- 0.1) than those of normal prostates (p less than 0.02) or prostates with benign hyperplasia (1.1 +/- 0.2, p less than 0.01). Malignant prostates had phosphomonoester-to-beta-ATP ratios (1.8 +/- 0.2) that were higher than that of normal prostates (p less than 0.02). Using the phosphomonoester-to-phosphocreatine ratio, it was possible to differentiate metabolically malignant (2.7 +/- 0.3) from normal prostates (p less than 0.001), with no overlap of individual ratios. The mean phosphomonoester-to-phosphocreatine ratio (1.5 +/- 0.5) of prostates with benign hyperplasia was midway between the normal and malignant ratios, and there was overlap between individual phosphomonoester-to-phosphocreatine ratios of benign prostatic hyperplasia glands with that of normal and malignant glands. To verify the in vivo results, we performed high resolution magnetic resonance spectroscopy on perchloric acid extracts of benign prostatic hyperplasia tissue obtained at operation and on a human prostatic cancer cell line DU145. The extract results confirmed the differences in metabolite ratios observed in vivo. We conclude that transrectal 31P magnetic resonance spectroscopy can characterize metabolic differences between the normal and malignant prostate.

Bladder substitution with ileocaecal (Mainz) pouch. Clinical performance over 2 years

A series of 11 patients underwent ileocaecal bladder substitution (Mainz pouch) with urethral anastomosis after radical cystectomy and pelvic lymphadenectomy for moderate to high grade transitional cell carcinoma of the bladder. With 12 to 27 months of follow-up (mean 18), 6 patients are voiding and are dry day and night with timed voidings; 4 patients continue intermittent catheterisation because of inability to perform the Valsalva manoeuvre adequately, and 1 has a suprapubic tube because of stricture of the enterourethral anastomosis. Upper tract studies revealed dilation of 4 of 22 renal units and 1 patient required endourological intervention. Serum electrolyte studies revealed slightly elevated chloride levels in 6, mild hypocarbia in 3, and reduced vitamin B12 levels in all patients, but no megaloblastic anaemia. The Mainz pouch appears to have very satisfactory short- and intermediate-term results.

Core biopsy instrument in the diagnosis of prostate cancer: superior accuracy to fine needle aspiration

The recent availability of an automated core biopsy gun has made the performance of core biopsies of the prostate easier and better tolerated. A prospective study was conducted to compare the efficacy of fine needle aspiration to core biopsy with the gun. Among 94 patients subjected to both biopsy techniques at the same visit 30 (32%) had a positive diagnosis of prostate cancer. Core biopsy was positive in these 30 patients (100%), while fine needle aspiration was positive in 21 (70%). This study suggests that core biopsy with the gun is superior to fine needle aspiration in the diagnosis of prostate cancer.

Nerve sparing and continence preservation during radical prostatectomy

Prostate cancer is one of the most common malignancies occurring in men. During the last decade, several advances have been made in decreasing the morbidity of surgical therapy. Two major advances have included an improved understanding of the physiology of erection and anatomy of pelvic parasympathetic nerves mediating erectile function. Surgical techniques of 'nerve preservation' during surgery can preserve postoperative potency in 50-70% of patients with localized prostate cancer. In others the use of intracorporal vasoactive agents, vacuum suction devices and surgical techniques can additionally improve potency. Knowledge of the various mechanisms contributing to continence have additionally enabled modifications in surgical techniques to enhance continence rates postoperatively. Currently postoperative continence after radical prostatectomy occurs in over 95% of patients.

N6-methyladenosine residues in an intron-specific region of prolactin pre-mRNA

N6-methyladenosine (m6A) residues occur at internal positions in most cellular and viral RNAs; both heterogeneous nuclear RNA and mRNA are involved. This modification arises by enzymatic transfer of a methyl group from S-adenosylmethionine to the central adenosine residue in the canonical sequence G/AAC. Thus far, m6A has been mapped to specific locations in eucaryotic mRNA and viral genomic RNA. We have now examined an intron-specific sequence of a modified bovine prolactin precursor RNA for the presence of this methylated nucleotide by using both transfected-cell systems and a cell-free system capable of methylating mRNA transcripts in vitro. The results indicate the final intron-specific sequence (intron D) of a prolactin RNA molecule does indeed possess m6A residues. When mapped to specific T1 oligonucleotides, the predominant site of methylation was found to be within the consensus sequence AGm6ACU. The level of m6A at this site is nonstoichiometric; approximately 24% of the molecules are modified in vivo. Methylation was detected at markedly reduced levels at other consensus sites within the intron but not in T1 oligonucleotides which do not contain either AAC or GAC consensus sequences. In an attempt to correlate mRNA methylation with processing, stably transfected CHO cells expressing augmented levels of bovine prolactin were treated with neplanocin A, an inhibitor of methylation. Under these conditions, the relative steady-state levels of the intron-containing nuclear precursor increased four to six times that found in control cells.

Prostatic oncology

Prostate cancer is the most common cancer in men in the United States. Management of prostatic cancer has evolved over the last two decades based on a clearer understanding of the natural history and on improvements in the techniques of radiation therapy, surgery, and hormonal manipulation. Additionally, better methods of prevention and treatment of complications have helped to provide curative therapies for more patients of all ages. Discussion on these topics is followed by a section on special problems in management of elderly patients with prostate cancer.