Mean diffusivity discriminates between prostate cancer with grade group 1&2 and grade groups equal to or greater than 3.

PURPOSE: To test the potential ability of mean diffusivity (MD) and fractional anisotropy (FA) in discriminating between PCa of grade group (GG) 1&2, and GGs≥3. MATERIAL AND METHODS: Diffusion Tensor Imaging (DTI) experiments at 3T in a cohort of 38 patients with PCa (fifty lesions in total) were performed, by using different diffusion weights (b values) up to 2500s/mm(2). Gleason score (GS) and GG data were correlated with DTI parameters (MD and FA) estimated in PCa. The relation between DTI measures and GS was tested by the linear correlation analysis (Pearson's coefficient). One-way analysis of variance to check the statistical significance of the difference between GG 1&2 and GGs 3, 4, 5, ≥3 was used. Results were reported for each of the three b-values ranges: 0-800s/mm(2), 0-1500s/mm(2), 0-2500s/mm(2). RESULTS: A negative correlation was found between MD and GS. The highest linear correlation was observed when the fit was performed with data acquired in the b-values range 0-2500s/mm(2). MD values were significantly different between GG 1&2 and GG=3 and between GG 1&2 and GG ≥3. Moreover this difference is better defined when high b values (higher than b=800s/mm(2)) are used. The specificity, sensitivity and accuracy in the discrimination between GG 1&2 and GG=3 were: 90%, 66.7% and 82.4%, respectively when MD was estimated in the b-values range 0-2500s/mm(2) while these values were 85%, 58.3% and 78.4% when MD was estimated in the b-values range 0-800s/mm(2). Conversely FA did not discriminate between GG 1&2 and GG ≥3, at any investigated b-values range. CONCLUSION: This study suggests that MD estimation in PCa, obtained from DTI acquired at high b-values, can contribute to the diagnosis and grading of prostate cancer while FA is not a useful parameter for this purpose.

Standardization of definitions in focal therapy of prostate cancer: report from a Delphi consensus project.

PURPOSE: To reach standardized terminology in focal therapy (FT) for prostate cancer (PCa). METHODS: A four-stage modified Delphi consensus project was undertaken among a panel of international experts in the field of FT for PCa. Data on terminology in FT was collected from the panel by three rounds of online questionnaires. During a face-to-face meeting on June 21, 2015, attended by 38 experts, all data from the online rounds were reviewed and recommendations for definitions were formulated. RESULTS: Consensus was attained on 23 of 27 topics; Targeted FT was defined as a lesion-based treatment strategy, treating all identified significant cancer foci; FT was generically defined as an anatomy-based (zonal) treatment strategy. Treatment failure due to the ablative energy inadequately destroying treated tissue is defined as ablation failure. In targeting failure the energy is not adequately applied to the tumor spatially and selection failure occurs when a patient was wrongfully selected for FT. No definition of biochemical recurrence can be recommended based on the current data. Important definitions for outcome measures are potency (minimum IIEF-5 score of 21), incontinence (new need for pads or leakage) and deterioration in urinary function (increase in IPSS >5 points). No agreement on the best quality of life tool was established, but UCLA-EPIC and EORTC-QLQ-30 were most commonly supported by the experts. A complete overview of statements is presented in the text. CONCLUSION: Focal therapy is an emerging field of PCa therapeutics. Standardization of definitions helps to create comparable research results and facilitate clear communication in clinical practice.

Bilateral Ureteral Obstruction in Children after Appendectomy.

Acute renal failure due to bilateral ureteral obstruction is a rare complication after appendectomy in children. We report a case of bilateral ureteric obstruction in a 14-year-old boy nine days after surgery for an acute appendicitis. After saline-filling of the urinary bladder, transabdominal ultrasound demonstrated bilateral hydronephrosis of moderate degree. No abscess was found with CT but presence of millimetric stones on both distal ureters was shown, with bilateral calyceal dilatation. Cystoscopy revealed inflammatory changes in the bladder base. Following introduction of bilateral ureteric stents, there was rapid normalisation of urinary output and serum creatinine.

Focal therapy for prostate cancer: current status and future perspectives.

Focal therapy is a relatively new and extremely attractive option of treatment for prostate cancer. It has been described as the "middle approach" between active surveillance and radical treatment, aiming to destroy the tumor itself or the region containing the tumor in order to preserve surrounding non-cancerous tissue. The goal is to maintain disease control at acceptable levels, while preserving erectile, urinary, and rectal function. While a lot of technologies have been described for delivering targeted therapy to the prostate, such as cryoablation, high intensity focused ultrasound, photodynamic therapy, irreversible electroporation and laser, the key point is the patient selection. Recent advances in mpMRI and the introduction of new biopsy techniques that use MR images as a guidance, have significantly improved localization of the tumor lesions and the detection rate, evolving prostate biopsy toward targeted rather than systematic biopsies. The future challenge to clinicians is to precisely risk-stratify patients to differentiate between those who would profit from focal treatment and who would not. Forthcoming research efforts should pursue to identify molecular, genetic, and imaging characteristics that distinguish aggressive prostate tumors from indolent lesions.

Prostate cancer diagnosis through electronic nose in the urine headspace setting: a pilot study.

BACKGROUND: To evaluate the efficacy of prostate cancer (PCa) detection by the electronic nose (EN) on human urine samples. METHODS: Urine samples were obtained from candidates of prostate biopsy (PB). Exclusion criteria were a history of urothelial carcinoma or other malignant disease, urine infection, fasting for <12 h before PB or ingestion of alcohol or foods that might alter the urine smell in the last 24 h. The initial part of the voided urine and the midstream were collected separately in two sterile containers. Both samples were analyzed by the EN immediately after the collection. All patients underwent a standard transperineal, transrectal-ultrasound-guided PB. The pathological results were compared with the outcomes of the EN. Sensitivity and specificity of EN were assessed. RESULTS: Forty-one men were included in the study. Fourteen out of the 41 patients were positive for PCa. Midstream urine did not correlate significantly neither with a positive nor with a negative PB. Instead, significantly different results on the initial part of the urine stream between positive and negative PBs were obtained. The EN correctly recognized 10 out of the 14 cases (that is, sensitivity 71.4% (confidence interval (CI) 42-92%)) of PCa while four were false negatives. Moreover, the device recognized as negative 25 out of the 27 (that is, specificity 92.6% (CI 76-99%)) samples of negative PBs, with only two false positives. CONCLUSIONS: We believe this is the first demonstration of an olfactory imprinting of the initial part of the urine stream in patients with PCa that was revealed by an EN, with high specificity.

Transperineal versus transrectal prostate biopsy for predicting the final laterality of prostate cancer: are they reliable enough to select patients for focal therapy? Results from a multicenter international study.

OBJECTIVES: To compare the concordance of prostate cancer (PCa) laterality between the extended transperineal (TP) or transrectal (TR) prostate biopsy (BP) and radical prostatectomy (RP) specimens. To identify predictors of laterality agreement between BP and RP. MATERIALS AND METHODS: Data from 533 consecutive patients with PCa (278 TP and 255 TR-diagnosed) treated with RP were analyzed. A 12-core technique was used for both TP and TR biopsies. Additional cores were obtained when necessary. RESULTS: Overall, the percentage of agreement of PCa laterality between BP and RP was 60% (K = 0.27, p < 0.001). However, the RP confirmation of unilaterality at BP was obtained in just 33% of the cases. Considering the concordance on bilaterality as the ″target″ of our analysis, the sensitivity and specificity were 54.3% and 98.2% , respectively, with TP and 47.5% and 92.5%, respectively with TR. Focusing on patients with unilaterality at biopsy, none of the evaluated preoperative variables (biopsy technique, age, total positive biopsy cores, PSA, prostate volume, Gleason score on biopsy) were able to predict RP bilaterality in the multivariate analyses. CONCLUSIONS: Most of the patients with unilateral involvement at BP harbored bilateral PCa after RP. TR and TP biopsy showed no difference in their capacity to predict the concordance of tumor laterality at RP. None of the preoperative evaluated variables can predict the tumor laterality at RP. Using BP unilaterality to include patients in focal therapy (FT) protocols may hinder the oncologic efficacy of FT.

Transperineal versus transrectal prostate biopsy for predicting the final laterality of prostate cancer: are they reliable enough to select patients for focal therapy? Results from a multicenter international study

Objectives: To compare the concordance of prostate cancer (PCa) laterality between the extended transperineal (TP) or transrectal (TR) prostate biopsy (BP) and radical prostatectomy (RP) specimens. To identify predictors of laterality agreement between BP and RP. Materials and Methods: Data from 533 consecutive patients with PCa (278 TP and 255 TR-diagnosed) treated with RP were analyzed. A 12-core technique was used for both TP and TR biopsies. Additional cores were obtained when necessary. Results: Overall, the percentage of agreement of PCa laterality between BP and RP was 60% (K = 0.27, p < 0.001). However, the RP confirmation of unilaterality at BP was obtained in just 33% of the cases. Considering the concordance on bilaterality as the “target” of our analysis, the sensitivity and specificity were 54.3% and 98.2%, respectively, with TP and 47.5% and 92.5%, respectively with TR. Focusing on patients with unilaterality at biopsy, none of the evaluated preoperative variables (biopsy technique, age, total positive biopsy cores, PSA, prostate volume, Gleason score on biopsy) were able to predict RP bilaterality in the multivariate analyses. Conclusions: Most of the patients with unilateral involvement at BP harbored bilateral PCa after RP. TR and TP biopsy showed no difference in their capacity to predict the concordance of tumor laterality at RP. None of the preoperative evaluated variables can predict the tumor laterality at RP. Using BP unilaterality to include patients in focal therapy (FT) protocols may hinder the oncologic efficacy of FT. .

DNA methylation silences miR-132 in prostate cancer.

Silencing of microRNAs (miRNAs) by promoter CpG island methylation may be an important mechanism in prostate carcinogenesis. To screen for epigenetically silenced miRNAs in prostate cancer (PCa), we treated prostate normal epithelial and carcinoma cells with 5-aza-2'-deoxycytidine (AZA) and subsequently examined expression changes of 650 miRNAs by megaplex stemloop reverse transcription-quantitative PCR. After applying a selection strategy, we analyzed the methylation status of CpG islands upstream to a subset of miRNAs by methylation-specific PCR. The CpG islands of miR-18b, miR-132, miR-34b/c, miR-148a, miR-450a and miR-542-3p showed methylation patterns congruent with their expression modulations in response to AZA. Methylation analysis of these CpG islands in a panel of 50 human prostate carcinoma specimens and 24 normal controls revealed miR-132 to be methylated in 42% of human cancer cases in a manner positively correlated to total Gleason score and tumor stage. Expression analysis of miR-132 in our tissue panel confirmed its downregulation in methylated tumors. Re-expression of miR-132 in PC3 cells induced cell detachment followed by cell death (anoikis). Two pro-survival proteins-heparin-binding epidermal growth factor and TALIN2-were confirmed as direct targets of miR-132. The results of this study point to miR-132 as a methylation-silenced miRNA with an antimetastatic role in PCa controlling cellular adhesion.

Malignant renal neoplasms: correlation between ADC values and cellularity in diffusion weighted magnetic resonance imaging at 3 T.

PURPOSE: This study aimed at exploring the feasibility of high-field diffusion-weighted magnetic resonance imaging (DW-MRI) (3 T) and to correlate apparent diffusion coefficient (ADC) values with tumour cellularity in renal malignancies. MATERIALS AND METHODS: Thirty-seven patients (ten healthy volunteers and 27 patients with suspected renal malignancy) underwent T1-, T2-weighted and T1-weighted contrast-enhanced magnetic resonance imaging (MRI). Diffusion-weighted images were obtained with a single-shot spin-echo echo-planar imaging (SE-EPI) sequence with a b value of 500 s/mm(2). All lesions were surgically resected, and mean tumour cellularity was calculated. Comparison between tumour cellularity and mean ADC value was performed using simple linear regression analysis. RESULTS: The mean ADC value in normal renal parenchyma was 2.35+/-0.31 x 10(-3) mm(2)/s, whereas mean ADC value in renal malignancies was 1.72+/-0.21 x 10(-3) mm(2)/s. In our population, there were no statistically significant differences between ADC values of different histological types. The analysis of mean ADC values showed an inverse linear correlation with cellularity in renal malignancies (r=-0.73, p<0.01). CONCLUSIONS: DW-MRI is able to differentiate between normal and neoplastic renal parenchyma on the basis of tissue cellularity.

Acute vs chronic effects of l-dopa on bladder function in patients with mild Parkinson disease.

OBJECTIVE: To compare acute and chronic effects of l-dopa on bladder function in levodopa-naive Parkinson disease (PD) patients who had urinary urgency. METHODS: We evaluated 26 l-dopa-naive PD patients at a university-based PD center with a first urodynamic session with a double examination: in the off treatment condition and 1 hour after acute challenge with carbidopa/l-dopa 50/200 mg; then, a chronic l-dopa monotherapy was administered (mean dose 300 +/- 150 mg). Two months later, patients underwent a second urodynamic session with a single evaluation 1 hour after the acute carbidopa/l-dopa challenge. RESULTS: The first acute l-dopa challenge significantly worsened bladder overactivity (neurogenic overactive detrusor contractions threshold [NDOC-t; 32% of worsening] and bladder capacity [BC; 22% of worsening]); on the contrary, l-dopa challenge during chronic administration ameliorated the first sensation of bladder filling (FS; 120% of improvement), NDOCT-t (93% improvement), and BC (33% of improvement) vs the values obtained with acute administration. An 86% significant improvement of FS in comparison with the basal value was observed. CONCLUSIONS: The acute and chronic l-dopa effects may be due to the different synaptic concentrations or to the activation of postsynaptic mechanisms obtained by chronic administration.

Effects of motor cortex rTMS on lower urinary tract dysfunction in multiple sclerosis.

We tested the effects of 5-Hz rTMS over the motor cortex in multiple sclerosis (MS) subjects complaining of lower urinary tract symptoms either in the filling or voiding phase. Our data show that motor cortex stimulation for five consecutive days over two weeks ameliorates the voiding phase of the micturition cycle, suggesting that enhancing corticospinal tract excitability might be useful to ameliorate detrusor contraction and/or urethral sphincter relaxation in MS patients with bladder dysfunction.

Posterior tibial nerve stimulation: is the once-a-week protocol the best option?

AIM: Aim of our study was to compare the results of posterior tibial nerve stimulation (PTNS) performed weekly with those of PTNS performed 3 times per week in patients with overactive bladder syndrome. METHODS: Thirty-five patients (28 females, 7 males) with overactive bladder syndrome not responding to antimuscarinic therapy were enrolled in a prospective study. A total of 17 out of 35 patients were randomly assigned to group A and treated with a PTNS protocol based on weekly stimulation sessions; 18 out of 35 patients were randomly assigned to group B and treated with a PTNS protocol based on stimulation sessions performed 3 times per week. All subjects were evaluated by means of 24 h bladder diaries, quality of life questionnaires (I-QoL, SF36) and urodynamic evaluation before and after treatment. Patients were asked after each stimulation session to give their opinion on the efficacy of the treatment. We have considered ''success'' those patients who presented a reduction >50% of the micturition episodes/24 h (ME/24) or (if incontinent) of the incontinence episodes/24 h (IE/24). Results before and after treatments in both groups were collected and statistically compared. RESULTS: As a whole, 11/17 patients (63%) in group A and 12/18 patients (67%) in group B were considered ''success''; 4/11 (36%) incontinent patients in group A and 5/11 (45%) incontinent patients in group B were completely cured after treatment. In both groups, patients reported subjective improvement after 6-8 stimulation sessions. CONCLUSIONS: Our findings seem to show that the periodicity of stimulation does not effect the results of PTNS treatment. The advantage of more frequent stimulation sessions is to achieve earlier a clinical improvement.

Evaluation of a new, rapid, qualitative, one-step PSA Test for prostate cancer screening: the PSA RapidScreen test.

To increase the acceptance rate and reduce the cost of the screening programme for prostate cancer, a new qualitative and one-step test for prostate-specific antigen (PSA), called PSA RapidScreen, has been evaluated. PSA RapidScreen test is a chromatographic lateral flow immunoassay, which generates a positive or negative result for PSA values >or=or <4 ng/ml, respectively. Capillary blood samples from 188 men were evaluated. Two independent observers interpreted the test at 10, 15, 20 and 25 min. A total of 10 women were tested as controls. Parallel serum samples were simultaneously collected and tested with an ordinary quantitative assay (Elecsys 2010, Roche). Sensitivity, specificity, accuracy, negative and positive predictive values of the test were 97.6, 90.4, 94, 98 and 89%, respectively. PSA RapidScreen tests on female capillary samples were negative. Reproducibility of the test was 99.5%, while interobserver variation was 5%. Specificity of the test was altered by variations in the reading time. Quantitative assessment of the intensity of the band correlated with the PSA value (r=0.87; t=23.97; P<0.001). PSA RapidScreen is a rapid, simple and reproducible one-step test. The low cost and the speed of the test make it a powerful and convenient tool for prostate cancer screening programmes.

Diffusion-weighted MR imaging in the evaluation of renal tumours.

The aim of this study was to evaluate the capability and the reliability of diffusion-weighted MR imaging to differentiate benign from malignant renal lesions. Twenty healthy volunteers and 48 patients with known renal lesions underwent MR of the kidneys by using a 1.5 T superconductive magnet. Diffusion-weighted images (DWI) were obtained on the axial plane during breathhold (17 s) with a SE EPI single shot sequence using a b value of 500 s/mm2. One region of interest (ROI) (lesions < than 3 cm) or 3 ROI (lesions > than 3 cm) were placed within the lesion for the measurement of apparent diffusion coefficient (ADC). ADC map was obtained at each slice position. Mean ADC value in normal renal parenchyma was 2.2 +/- 0.20 x 10(-3) mm2/s, while ADC values in simple cysts (n = 20) were higher (mean ADC values 3.65 +/- 0.09 x 10(-3) mm2/s). Solid benign and malignant renal tumors (n = 19) showed a mean ADC value of 1.7 +/- 0.48 x 10(-3) mm2/sec. The comparison between ADC values in normal parenchyma group and tumour group were found to be statistically significant (p < 0.0001). ADC values of cystic renal cell carcinomas were higher than those of clear cell carcinomas (p < 0.001). In conclusion, DW MRI of the kidney seems to be a reliable means for differentiating normal renal parenchyma from different renal tumors.

Double-J ureteral stents: an alternative to external urinary stents in orthotopic bladder substitution.

OBJECTIVE: The aim of this study was to compare advantages and disadvantages of using double-J or external stents to preserve the uretero-ileal anastomosis in patients receiving an orthotopic neobladder. METHODS: 77 consecutive patients with bladder cancer who underwent radical cystoprostatectomy and Studer neobladder were evaluated. All patients received a direct spatulated end-to-side uretero-ileal anastomosis in the afferent loop (Nesbit technique). In 45 patients (group A), the stents (Bracci ureteral splint) were brought our through the reservoir and anchored to the skin; in 32 patients (group B), an internal double-J stent was used. Median follow-up was 30 months. RESULTS: 9 (11.5%) uretero-ileal anastomosis strictures in group A and 7 (11.6%) in group B were observed. There was a significant difference in the side of stricture with a greater prevalence on the left side (p<0.004). Stricture formation and side were not related to the type of stent used. 14 (20%) neobladder-ureteral refluxes occurred, with a non-significant difference between the two groups (p = 0.37). 12 patients (86%) were asymptomatic; two patients developed pyelonephritis and needed antibiotic treatment. Neobladder catheter was removed after 17 days (range: 15-18 days) and 14 days (range: 12-15 days), respectively, in group A and group B with an earlier discharge of the patients in group B. There was a significant difference in mean hospital stay between the two groups (Mann-Whitney test p<0.0001). Discomfort related to the stent was mild for most of the patients of group B (84%). CONCLUSIONS: Internal stenting is an equally effective alternative to external stent in patients undergoing bladder replacement. The use of double-j stents appears to be associated with minimal discomfort, earlier mobilization and a shorter hospital stay.

Right varicocele associated with inferior vena cava malformation in situs inversus: percutaneous treatment with retrograde sclerotherapy.

Isolated right varicocele is a rare condition. It could be secondary to a retroperitoneal neoplastic mass involving the right internal spermatic vein, but sometimes, an anatomic variant must be considered. We present a case of a young man with situs inversus and right varicocele, a mirror image of the normal condition, associated with inferior vena cava malformation, who was treated successfully with retrograde selective percutaneous sclerotherapy of the right internal spermatic vein. Selective sclerotherapy of the internal spermatic vein at the time of venography has proved to be a valuable therapeutic option in right-sided varicocele associated with anatomic abnormalities.

Undetectable ultrasensitive PSA after radical prostatectomy for prostate cancer predicts relapse-free survival.

Radical retropubic prostatectomy is considered by many centres to be the treatment of choice for men aged less than 70 years with localized prostate cancer. A rise in serum prostate-specific antigen after radical prostatectomy occurs in 10-40% of cases. This study evaluates the usefulness of novel ultrasensitive PSA assays in the early detection of biochemical relapse. 200 patients of mean age 61. 2 years underwent radical retropubic prostatectomy. Levels < or = 0.01 ng ml-1 were considered undetectable. Mean pre-operative prostate-specific antigen was 13.3 ng ml-1. Biochemical relapse was defined as 3 consecutive rises. The 2-year biochemical disease-free survival for the 134 patients with evaluable prostate-specific antigen nadir data was 61.1% (95% CI: 51.6-70.6%). Only 2 patients with an undetectable prostate-specific antigen after radical retropubic prostatectomy biochemically relapsed (3%), compared to 47 relapses out of 61 patients (75%) who did not reach this level. Cox multivariate analysis confirms prostate-specific antigen nadir < or = 0.01 ng ml-1 to be a superb independent variable predicting a favourable biochemical disease-free survival (P < 0.0001). Early diagnosis of biochemical relapse is feasible with sensitive prostate-specific antigen assays. These assays more accurately measure the prostate-specific antigen nadir, which is an excellent predictor of biochemical disease-free survival. Thus, sensitive prostate-specific antigen assays offer accurate prognostic information and expedite decision-making regarding the use of salvage prostate-bed radiotherapy or hormone therapy.

Extracorporeal piezoelectric shockwave lithotripsy of ureteral stones: are second-generation lithotripters obsolete?

BACKGROUND: The role of extracorporeal shockwave lithotripsy (SWL) for ureteral calculi is still being debated. We evaluated our results in a large series to clarify the role of this modality. PATIENTS AND METHODS: A total of 478 patients with solitary ureteral stones were treated by in situ piezoelectric extracorporeal shockwave lithotripsy (SWL) using a Wolf Piezolith 2300 ultrasound-guided lithotripter. Two hundred fifty stones (52.3%) were located in the upper ureter and 228 (47.7%) in the distal ureter. Seventy of the upper ureteral stones were located in the ureteropelvic junction and 180 in the lumbar ureter. The diameter of the stones ranged from 5 to 30 mm. Four hundred sixty-seven patients were followed up for a mean of 4 months. RESULTS: Four hundred forty patients (94.2%) were stone free after in situ SWL alone. Complete removal of all stone fragments was achieved in 95.4% of the 216 patients with calculi of 5 to 10 mm in diameter, in 94.3% of the 229 with stones of 11 to 20 mm, and in 81.8% of the 22 with calculi of 21 to 30 mm. In situ treatment completely removed 61 of 69 ureteropelvic junction stones (88.4%), 166 of 175 lumbar stones (94.8%), and 213 of 223 distal ureteral stones (95.5%). In situ treatment failed in 27 stones (5.8%). After 4 months, 12 stone fragments and 15 unfragmented stones persisted despite retreatments and required endoscopic procedures. The mean number of sessions and shockwaves per patient was 1.8 and 4884, respectively. Morbidity was low. Renal colic in 57 patients (11.9%) was managed successfully by analgesics. In 36 patients, stone fragments obstructed the ureter; in 28 of these 36 (78%), the obstruction was resolved and the patients were stone free after in situ retreatments alone. All these results were achieved on an outpatient basis without sedation or local or general anesthesia. CONCLUSION: Piezoelectric SWL is an effective and noninvasive method for eliminating ureteral stones. Second-generation ultrasound-guided lithotripters are not yet obsolete.

Increased matrix metalloproteinase-9 secretion in short-term tissue cultures of prostatic tumor cells.

We have examined the expression of 2 tumor-associated metalloproteinases, MMP-2 and MMP-9, in 48 primary cultures of prostatic carcinoma (PRCA) and 33 cultures of benign prostatic hyperplasia (BPH). PRCA cultures secrete significantly more MMP-9 than their benign counterparts. Secreted MMP-2 did not differ significantly in cultures but was lower in PRCA cultures. Two cultures of benign origin exhibited high MMP-9 secretion and growth patterns consistent with a malignancy. Both cases were followed and successively re-evaluated histologically and rediagnosed as organ-confined PRCA. MMP expression in culture may be of predictive value in the identification of incidental PRCA. MMP-9 secretion and its ratio with MMP-2 were highest in epithelial cultures from invasive, metastatic tumors when compared both to disease confined to prostate gland and to locally extensive disease. MMP-9 secretion was greatest also in cultures derived from tissues of high Gleason histological grade. Active MMP-9 species were detected in 15 cultures (31%) of PRCA. Active MMP-2 species were observed in cultures of both BPH and PRCA origin in almost the same amounts. Although average levels were not significantly different, as a ratio to proform species, a significant elevation was observed in cultures of PRCA origin. We propose, therefore, that an elevated expression of MMP-9 and a high ratio of MMP-9 to MMP-2 in short-term prostate epithelial cultures is of potential diagnostic and prognostic significance.