Detection of prostate carcinoma using prostate specific antigen, its density, and the density of the transition zone in Japanese men with intermediate serum prostate specific antigen concentrations

Any Correlation Between Prostate Volume and Incidence of Prostate Cancer: A Review of Reported Data for the Last Thirty Years

PURPOSE

Prostate cancer (PCa) is the most common non-skin cancer in men worldwide and more than 80% of men with PCa also have histo-anatomical findings of benign prostate hyperplasia (BPH). It is well documented that BPH develops in the transition zone (TZ), whereas 80-85% of PCa originates in the peripheral zone (PZ) of the prostate. Possible causal links between both disease entities are controversially discussed in the current literature. Some studies have reported that larger prostates have a decreased incidence of PCa compared to smaller prostates. The purpose of this systematic review is to comprehensively summarize studies analyzing any association between prostate gland volume and incidence of PCa.

METHODS

A thorough literature review was performed between 01.01.1990 through 02.28.2020 using PubMed and applying the "PRISMA" guidelines. Inclusion and exclusion criteria were defined.

RESULTS

Our systematic review found 41 articles reporting an inverse (negative) relationship between prostate gland volume and incidence of prostate cancer. Sample sizes ranged from 114 to 6692 patients in these single institutional and multi-institutional studies. Thirty-nine (95%) of the 41 articles showed a statistically significant inverse relationship. In our search, no study was found showing a positive correlation between BPH size and the incidence of PCa.

CONCLUSION

To our knowledge, this is the first systematic review on the important clinical question of interaction between prostate size and the incidence of PCa. The results are demonstrating an inverse relationship, and therefore reveal strong evidence that large prostates may be protective of PCa when compared to smaller prostates.

The Clinical Efficacy of Prostate Cancer Screening in Worldwide and Iran: Narrative Review

Prostate cancer (CaP) imposes a great health burden on men, while its incidence has significantly increased in recent years. The screening program for CaP is still controversial and recent large trials have failed to present a significant reduction in prostate-specific mortality and all-cause mortality. An entire body of data obtained from worldwide studies conducted on CaP screening is required to better evaluate health policy decisions and patient decision-making. In current review, the clinical efficacy of screening programs on CaP was discussed in numerous parts of the world, such as in the US, Europe, and Asia, to provide an updated screening recommendation. Finally, we discuss about CaP screening status in Iran and update the screening recommendation in Iran.

Evaluation of prostate cancer prevalence in Iranian male population with increased PSA level, a one center experience

PURPOSE

This study was conducted to evaluate the incidence of prostate cancer (PCa) in Iranian male patients with increased prostate-specific antigen (PSA), and normal or abnormal digital rectal examination (DRE) that underwent prostate biopsy.

MATERIALS AND METHODS

From March 2006 to April 2009, a total of 346 consecutive males suspected of having PCa due to increased PSA levels underwent transrectal ultrasonography (TRUS)-guided sextant biopsy of the prostate. The total PSA (tPSA), demographic data, incidence of PCa, benign prostate hyperplasia (BPH), and prostatitis were assessed.

RESULTS

The patients were divided into two groups according to their PSA values (group A serum tPSA level, 4-10 ng/mL; group B serum tPSA level, 10.1-20.0 ng/mL). Of the 346 biopsied cases, 193 cases (56%) had PCa, 80 cases (23%) had BPH, and 73 cases (21%) had prostatitis. The mean PSA and the age of the carcinoma group were significantly higher than those of the benign group (P < 0.01). The biopsy results were grouped as PCa, BPH, and prostatitis. Incidence of PCa for group A and group B cases were 115 cases (51%), and 78 cases (65%), respectively. In the case of PCa, BPH, and prostatitis, the mean PSAs were 10.02 ng/mL, 8.76 ng/mL, and 8.41 ng/mL, respectively (P < 0.40).

CONCLUSION

TRUS-guided prostate biopsy and interpretation by a skilled team is highly recommended for early detection of PCa or its ruling-out. It seems that a PSA cutoff value of 4 ng/mL may be applied to the Iranian population. Although the chance of PCa is high in the PSA levels of 4-10 ng/mL, the combination of some data, like age and prostate volume, can decrease the rate of unnecessary prostate biopsies. We recommend prostate biopsy when PSA and/or DRE is elevated in symptomatic patients with obstructive and/or irritative lower urinary tract symptoms (LUTS) such as dysuria, frequency, or nocturia. Due to the very high incidence of PCa in the patients with PSA greater than 10 ng/mL, TRUS-guided biopsy is indicated, whatever the findings on DRE and/or LUTS, since the PCa detection rate is high.

Initial biopsy outcome prediction in Korean patients-comparison of a noble web-based Korean prostate cancer risk calculator versus prostate-specific antigen testing

We developed and validated a novel Korean prostate cancer risk calculator (KPCRC) for predicting the probability of a positive initial prostate biopsy in a Korean population. Data were collected from 602 Koreans who underwent initial prostate biopsies due to an increased level of prostate-specific antigen (PSA), a palpable nodule upon digital rectal examination (DRE), or a hypoechoic lesion upon transrectal ultrasound (TRUS). The clinical and laboratory variables were analyzed by simple and multiple logistic regression analysis. The area under the receiver operating characteristic curve (AUC) was computed to compare its performance to PSA testing alone. Prostate cancer was detected in 172 (28.6%) men. Independent predictors included age, DRE findings, PSA level, and prostate transitional zone volume. We developed the KPCRC using these variables. The AUC for the selected model was 0.91, and that of PSA testing alone was 0.83 (P < 0.001). The AUC for the selected model with an additional dataset was 0.79, and that of PSA testing alone was 0.73 (P = 0.004). The calculator is available on the website: http://pcrc.korea.ac.kr. The KPCRC improved the performance of PSA testing alone in predicting the risk of prostate cancer in a Korean population. This calculator would be a practical tool for physicians and patients.

Safety and efficacy of combined transrectal ultrasound-guided prostate needle biopsy and transurethral resection of the prostate

Purpose

This study was conducted to examine whether simultaneous transrectal prostate needle biopsy (TPNB) owing to an increase in prostate-specific antigen (PSA) levels is safe and effective in patients who are scheduled for transurethral resection of the prostate (TURP) for benign prostatic hyperplasia (BPH).

Materials and Methods

Combined TPNB and TURP was performed in a total of 42 patients aged 60 years and older who had gray-zone PSA values (4-10 ng/ml) and PSA density (PSAD) values of 0.12 and less. The frequencies of fever, sepsis, and epididymitis were assessed after surgery. The diagnostic accuracy was assessed, and the results of histologic examination were evaluated in terms of TPNB or TURP. In addition, the diagnostic accuracy was assessed according to age.

Results

Prostate cancer was diagnosed in 6 (14.3%) of the 42 patients: 2 patients were diagnosed with prostate cancer by TPNB only, 3 patients by TURP only, and 1 patient by combined TPNB and TURP. Four (25%) of the 16 patients aged under 70 years and 2 (7.8%) of the 26 patients aged 70 years and older were diagnosed with prostate cancer. Fever was observed in 9 patients (21.4%), 4 (9.5%) of whom had a fever of higher than 38℃. The fever normalized the day after surgery in all 9 patients. No septicemia was noted. There were no serious complications related to combined TPNB and TURP.

Conclusions

The results of this study suggest that combined TPNB and TURP may be safe and effective in patients who require TURP.

The potential role of prebiopsy magnetic resonance imaging combined with prostate-specific antigen density in the detection of prostate cancer

AIM

Two-thirds of patients with a gray-zone prostate-specific antigen (PSA) level undergo unnecessary biopsy. Sensitivity is not yet sufficient to permit the use of modified PSA parameters or magnetic resonance (MR) imaging alone for prostate cancer screening. Thus, we evaluated the combination of MR imaging and PSA density (PSAD) for specificity and sensitivity.

METHODS

During the period April 2004 through March 2006, 185 patients with a PSA level of 4.0-10.0 ng/mL underwent MR imaging and transrectal ultrasonography-guided 8-core biopsy (systemic sextant biopsy of the peripheral zone plus two cores of transition zone). All MR images were interpreted prospectively by two radiologists. An image was considered positive for prostate cancer if any feature indicated a cancerous lesion. Receiver operating characteristic (ROC) curves were used to compare the usefulness of the PSA level, PSAD and PSA transitional zone density (PSATZ) for the detection of prostate cancer.

RESULTS

Of the 185 patients, 62 had prostate cancer. Sensitivity and specificity of the axial T2-weighted MR imaging findings for cancer detection were 79.0% and 59.4%, respectively. The area under the ROC curve was 0.590 for the PSA level, 0.718 for PSAD and 0.695 for PSATZ. MR imaging findings and PSAD were shown by multivariate analysis to be statistically significant independent predictors of prostate cancer (P < 0.001). With a PSAD cut-off value of 0.111, sensitivity was 96.8%, but specificity was 19.5%. Combining MR imaging findings with PSAD increased the specificity to 40% and retained 95% sensitivity.

CONCLUSION

MR imaging findings combined with PSAD provide high sensitivity and improve the specificity for the early detection of prostate cancer.

Progensa PCA3 test for prostate cancer detection

Patients with an elevated serum total prostate-specific antigen value or abnormal digital rectal examination results are at risk of having prostate cancer and should undergo prostate needle biopsies. However, approximately 60% of them will have a negative prostate biopsy result. Therefore, further biopsies are recommended for young patients at risk of prostate cancer with a positive rate of 20-40%. Biomarkers are required in order to avoid unnecessary biopsies. The PCA3 gene product is specifically overexpressed in prostate tumor cells, and modern molecular biology techniques allow us to use a specific test for this gene in order to select patients who have a high risk of having prostate cancer. Literature reviews of the gene product, as well as the first clinical results of the Progensa PCA3 test, are presented.

Hepatocyte growth factor and interleukin-6 in combination with prostate volume are possible prostate cancer tumor markers in patients with gray-zone PSA levels

The aim was to assess whether hepatocyte growth factor (HGF) and interleukin (IL)-6 in combination with prostate volume are able to accurately detect prostate cancer in patients with gray-zone prostate-specific antigen (PSA) levels. A total of 159 patients with PSA levels of <10 ng ml(-1) were enrolled. Forty-two (35.3%) were diagnosed with prostate cancer, whereas 117 (64.7%) had no cancer and were used as benign group. HGF and IL-6 density (HGFD and IL-6D, respectively) values were calculated by dividing serum HGF and IL-6 levels with prostate volume. Median IL-6 (2.3 pg ml(-1)) levels for the prostate cancer group were significantly higher than those for the benign group before adjustment for age (1.7 pg ml(-1)) (P=0.0098). After age adjustments, median IL-6 (2.17 pg ml(-1)), HGFD (0.00972 ng ml(-1) cm(-3)), and IL-6D (0.0848 pg ml(-1) cm(-3)) values for the prostate cancer group were significantly higher than those for the benign group (IL-6, 1.78 pg ml(-1); HGFD, 0.00732 ng/ml/cc; and IL-6D, 0.049 pg/ml/cc; P=0.0416, 0.007 and 0.0005, respectively). In receiver operating characteristic analyses, the areas under the curves for HGFD (0.64) and IL-6D (0.68) were significantly greater than those for HGF (0.52) and IL-6 (0.61) (P=0.0006 and 0.019, respectively). With an HGFD cutoff value of 0.00392 ng ml(-1) cm(-3) (sensitivity=100%, specificity=11%), 11.1% of the benign group were able to avoid unnecessary biopsies without missing prostate cancer. HGF and IL-6 levels in combination with prostate volume were shown to be useful parameters for prostate cancer screening in patients with gray-zone PSA levels.

Incidental prostatic adenocarcinoma in patients with PSA less than 4 ng/ml undergoing radical cystoprostatectomy for bladder cancer in iranian men

OBJECTIVE

To assess the incidence of prostate adenocarcinoma in patients undergoing radical cystoprostatectomy due to bladder cancer in Iranian men.

MATERIALS AND METHODS

Fifty cystoprostatectomy specimens removed due to bladder malignancy (2004-2005) at two referral centers (Shaheed Modarress and Shaheed Labbafinejad Hospitals, Tehran, Iran) were examined for the coincidental finding of prostate cancer (PCa). At the time of surgery the patient's serum PSA was less than 4 ng/mL and there were no suspicious lesions by digital rectal examination. Pathologic grade, stage, morphometric volume, number of tumor foci and association with areas of high grade prostatic intraepithelial neoplasia (HGPIN) were assessed by light microscopy. All specimens were totally embedded and whole-mounted. Clinically significant cancers were defined as tumors with >or= 0.5 mL volume, Gleason pattern 4 or 5, pT3, positive surgical margin, and multifocality > 3.

RESULTS

Incidentally detected cancer was found in 7 (14%) of cystoprostatectomy specimens. HGPIN was present in 1 (14.3%) of the cystoprostatectomies with incidentally detected prostate cancer. None of cystoprostatectomies without prostate cancer had HGPIN. Four (57%) of the detected cancers were significant.

CONCLUSION

We conclude that incidentally detected prostate cancer in Iran is lower than the rates reported in other countries. Further studies are warranted for better declaration of variability of prostate cancer between different ethnic groups.

Population-based screening for prostate cancer by measuring free and total serum prostate-specific antigen in Iran

PURPOSE

To evaluate the natural background of prostate cancer in Iran a large population-based study of screening using total prostate-specific antigen (tPSA) and per cent free PSA (fPSA) as the initial test was performed.

MATERIALS AND METHODS

For 9 years (1996 to 2004) in Tehran, Iran, 3670 Iranian men older than 40 years were mass checked by PSA-based screening. They were invited to have a digital rectal examination (DRE), serum PSA assay and transrectal ultrasonography (TRUS)-guided sextant prostate biopsy to see if the DRE was clinically suspicious of malignancy, the serum PSA was > or =2.1 ng/ml or free-to-total PSA (f/tPSA) ratio < or=15%.

RESULTS

In 433 (11.8%) of screened males, tPSA levels exceeded the cut-off value of > or =2.1 ng/ml and 128 prostate cancers were diagnosed [positive predictive value (PPV) 29.6%] corresponding to an overall detection rate of 3.5%. Altogether 138 cancers were detected (detection rate 3.8%); none were stage M(1), three were stage N(+) and 4 stage T(3). A threshold tPSA of > or =2.1 ng/ml would have detected 128 cancers in 447 biopsied men (PPV 29%). There were 109 of 138 (79%) men with cancer who had an f/tPSA of < or =15%, while 152 of 305 (49.8%) with benign biopsies had a f/tPSA of < or =15%, which corresponds to a PPV of 30.8%.

CONCLUSION

PSA-based screening with low PSA cut-off values increase the detection rate of clinically significant, organ confined and potentially curable prostate cancer. Further studies are warranted in order to determine the incidence and prevalence of prostate cancer in different ethnic groups.

Utility of volume adjusted prostate specific antigen density in the diagnosis of prostate cancer in Arab men

BACKGROUND

This study was undertaken to assess the utility of prostate specific antigen (PSA) and PSA density (PSAD) in discriminating between benign and malignant prostate disease in the Kuwaiti Arab population.

METHODS

A total of 100 consecutive patients suspected of having prostate cancer because of serum PSA > 4 ng/ml, or detection of a prostatic nodule on rectal examination were further investigated by determination of PSAD, TRUS of prostate, sexant prostatic biopsy and histological analysis to establish the correct diagnosis. Other diagnostic measures included the determination of the area under the receiver operating characteristic (ROC) curve, sensitivity and specificity.

RESULTS

Of the 100 prostate biopsies that were performed, 33 cases were confirmed to be prostate cancer and 67 were described as benign lesions comprising benign prostatic hyperplasia (BPH) with or without prostatitis. The age range for patients with prostate cancer was 42-90 years, and 52-90 years for those without prostate cancer. The mean prostate volume was 58.82 cc (range 9-177 cc) and 62.60 cc (range 15-140 cc), the mean PSA value was 36.65 ng/ml (range 5.8-200 ng/ml) and 16.49 ng/ml (range 1.4-46.0 ng/ml), while the mean PSAD was 0.92 (range 0.046-5.714) and 0.452 (range 0.034-2.294) for patients with prostate cancer and patients without prostate cancer respectively. Patients with PSA less than 4 ng/ml (3 cases) all had benign prostate lesions, and 7 cases with PSA more than 50 ng/ml all had prostate cancer and were excluded because values above 50 ng/ml have close to 100% specificity for prostate cancer. Further analysis was done on the remaining 90 cases which were patients with a PSA between 4 and 50 ng/ml. The discriminating power of serum PSA for detecting prostate cancer as estimated by the area under ROC was 0.686 while that for PSAD was 0.732. The maximum likelihood for a positive PSA was at a PSAD cut-off point of 0.32. For the PSA cut-off point of l0 ng/ml, the sensitivity was 80%, and specificity was 42.2%. For the PSAD cut-off point of 0.32, the sensitivity was 58% and the specificity 76.6%.

CONCLUSIONS

Determination of PSAD is not a useful adjunct to serum PSA values in the range of 10-50 ng/ ml in our population. PSAD value less than 0.32 with PSA less than l0 ng/ml strongly suggests benign disease.

Assessment of serum level of prostate-specific antigen adjusted for the transition zone volume in early detection of prostate cancer

OBJECTIVE

To determine the clinical usefulness of prostate-specific antigen (PSA) density in the transition zone (PSADTZ) for increasing the specificity in early detection of prostate cancer (PCa) and reducing unnecessary biopsies in males with PSA between 4.0 and 10 ng/mL.

MATERIALS AND METHODS

This cross-sectional study obtained PSADTZ measurements in 68 patients with PSA between 4.0 and 10 ng/mL. All patients underwent transrectal ultrasonography (TRUS) with biopsies. PSADTZ was estimated by dividing the PSA value by the volume of the transition zone (TZ) obtained. We compared performance measurements for these parameters with those from the PSA itself, PSA density (PSAD) and free PSA/total PSA ratio (F/T PSA). The ability of the method in increasing PSA specificity was demonstrated and compared in univariate and multivariate analyses, and by Receiver Operating Characteristic Curves (ROC).

RESULTS

Of the 68 patients under study, 17 (25%) were diagnosed with PCa. The TZ volume (p = 0.001) and PSADTZ (p = 0.001) variables presented means that exhibited statistically significant differences. When compared with the area under the curve (AUC), ROC curves obtained by this method revealed that PSADTZ was the strongest predictor for PCa when considering the cut-off point provided by the curve; that is, 0.35 ng/mL/cc. When PSADTZ was employed, the detection failure would be close to 20%, and less than 45% of cases would undergo unnecessary biopsies. On the other hand, when F/T PSA was used, the loss would reach almost 40%; however less than 30% would undergo unnecessary biopsies. Nevertheless, PSADTZ had the only AUC presenting p < 0.05 in significance when compared with 50%, and was consequently discriminative.

CONCLUSIONS

PSADTZ increased PSA specificity in early detection of PCa in males with PSA between 4.0 and 10 ng/mL. However, it was shown to have lower predictive value and lower accuracy than the percentage of free PSA since it presents a higher negative predictive value than all other parameters assessed, and it can be considered clinically useful for reducing unnecessary indications for biopsy.

Evaluación del antígeno especifico prostático (PSA) ajustado al volumen de la zona transicional en la detección del cáncer de próstata

OBJECTIVE

To investigate if PSA adjusted to transition zone (PSA-TZ) can be considered as a predictor parameter of cancer with better specificity or not than PSA, PSA density (PSAD) or PSA free/total ratio.

MATERIAL AND METHODS

Data of 706 patients with sextant prostatic biopsies are analyzed in prospective way because of prostatic cancer suspicion. Range of PSA was between 4 to 20 ng/ml. Determination of PSA-TZ was calculated by dividing the PSA value by the volume of the transition zone of the prostate applying the ellipsoid formula and comparison of obtained results in detection of cancer was performed by ROC curves analysis for each one of PSA-related parameters.

RESULTS

Of the total group of patients, in 199 cases (28.2%) prostatic cancer was detected. Analysis by ROC curves demonstrated than PSA-TZ and PSAD were better predictors of cancer than PSA free/total ratio and PSA (p < 0.0001). The cutoff value of PSA-TZ of 0.18 ng/ml/cc was considered as the best, obtaining a 95% sensitivity and a 27% specificity. For this sensitivity, PSA, PSAD and PSA free/total ratio only obtained 5, 9 and 16% specificity respectively. Areas under curve (AUC) obtained for PSA, PSA free/total ratio, PSAD and PSA-TZ were 0.539, 0.612, 0.694 and 0.722 respectively.

CONCLUSIONS

PSA-TZ in the studied population was a parameter with better diagnostic specificity than PSA, PSAD and PSA free/total ratio for the same 95% sensitivity. This would justify its utility in clinical paractice reducing the number of unnecesary biopsies.

The ratio of prostate-specific antigen (PSA) to prostate volume (PSA density) as a parameter to improve the detection of prostate carcinoma in PSA values in the range of < 4 ng/mL

BACKGROUND

The objective of this study was to evaluate the prostate specific antigen (PSA) density (PSAD) (the quotient of PSA and prostate volume) compared with the percent free PSA (%fPSA) in different total PSA (tPSA) ranges from 2 ng/mL to 20 ng/mL. Possible cut-off levels depending on the tPSA should be established.

METHODS

In total, 1809 men with no pretreatment of the prostate were enrolled between 1996 and 2004. Total and free PSA were measured with the IMMULITE PSA and Free PSA kits (Diagnostic Products, Los Angeles, CA). Prostate volume was determined by transrectal ultrasound. The diagnostic validity of tPSA, %fPSA, and PSAD was evaluated by receiver operation characteristic (ROC) curve analysis.

RESULTS

The PSAD differed significantly (P < 0.0001) between patients with prostate carcinoma and patients with benign prostatic hyperplasia in all analyzed ranges of tPSA and prostate volume. At the 90% and 95% sensitivity levels and regarding the area under the ROC curve (AUC) within the tPSA range of 2-4 ng/mL, The PSAD was significantly better than tPSA and %fPSA. Within the tPSA range of 4-10 ng/mL, the PSAD did not perform better than %fPSA.

CONCLUSIONS

PSAD showed a better performance than %fPSA at tPSA concentrations < 4 ng/mL for detecting prostate carcinoma, with a significantly larger AUC for PSAD (0.739) compared with %fPSA (0.667). PSAD did not perform better than %fPSA when the tPSA range of 4-10 ng/mL was analyzed. Different PSAD cut-off values of 0.05 at tPSA 2-4 ng/mL, 0.1 at tPSA 4-10 ng/mL, and 0.19 at 10-20 ng/mL were necessary to reach 95% sensitivity.

[Value of prostate-specific antigen density and transitional-zone prostate-specific antigen density in the diagnosis of prostate cancer]

INTRODUCTION

With serum prostate specific antigen (PSA) levels of 4.1 to 10 ng/ml a significant number of patients are unnecessary subjected to biopsy. We try to determine if the calculation of prostate specific antigen density (PSAD) and prostate specific antigen density of the transition zone (PSADTZ) improve the capacity to discriminate between non-malignant disease and prostate cancer.

METHODS

A prospective study including 314 males with PSA levels between 4.1 and 10 ng/ml is reported. Transrectal ultrasonography and prostatic biopsy were performed in all of them and total prostate and transition-zone volumes were calculated. PSA density and PSA density of the transition zone were calculated for each patient. Receiver operating characteristics (ROC) curves for PSA, PSAD and PSADTZ were constructed for all the patients and for those patients with digital rectal examination unsuspicous of malignancy, determining the sensitivity and specificity for several cutoff values.

RESULTS

The area under the curve for both, PSAD and PSADTZ, were greater than for PSA (p < 0.05), without any significant differences between PSADTZ and PSAD. The cutoff value of greatest diagnostic efficiency for PSAD was 0.17 ng/ml/cc (71.4% sensitivity and 55.7% specificity), while it was 0.41 ng/ml/cc for DPSATZ (70% sensitivity and 61.5% specificity). For those cases of normal digital rectal examination, no differences were observed between PSA and PSAD but they were between PSA and PSADTZ. In any event, the area under ROC curves was always less than 0.7, and, in order to avoid a large number of biopsies (high specificity), a large number of cancers are left without diagnosis (low sensitivity).

CONCLUSIONS

We conclude that PSAD and PSADTZ are not excessively useful for adequately discriminating between patients with prostate cancer and those with non-malignant disease, particularly when digital rectal examination is normal.

Improved detection rate of prostate cancer using the 10-core biopsy strategy in Singapore

OBJECTIVES

To evaluate if changing the biopsy regime to 10 cores might improve the positive predictive value (PPV) of elevated prostate-specific antigen [PSA, elevated range, 4 to 20 ng per ml, normal range, < 4 ng per ml] for the diagnosis of prostate carcinoma.

METHODS

From February 2000 to April 2001, 191 patients, mean age 64 years [range, 38 to 85 yr], underwent transrectal ultrasound [TRUS] for either elevated PSA [elevated range, 4 to 20 ng per ml] and/or abnormal digital rectal examination [DRE]. A 10-core TRUS-guided biopsy of the prostate was performed. This included the standard sextant biopsy and two additional cores for each far lateral zone.

RESULTS

Using this technique, 47 out of 191 patients [24.6%] had prostate cancer. The PPV for PSA levels of 4.1 to 10.0 ng per ml and 10.1 to 20.0 ng per ml were 19.3% and 35.4%, respectively. The lateral cores contributed 21.3% of the cancer cases, which would have been missed if only sextant biopsies were performed.

CONCLUSIONS

With the 10-core biopsy method, the PPV for prostate cancer for patients with a PSA in the range of 4 to 20 ng per ml was in the range of 25%. This is significantly different from previous reports. The reason for this may be due to the adoption of a better, more uniform and systematic biopsy strategy for patients with elevated PSA, or it may be a true reflection of the current population incidence. Hence, this biopsy strategy is highly recommended.

Likelihood of prostate cancer based on prostate-specific antigen density by MRI: retrospective analysis

OBJECTIVE

As a screening test for prostate cancer (PCA), prostate-specific antigen (PSA) may induce unnecessary prostate biopsy in patients with PSA 4.1-10.0 ng/ml. PCA detection may be delayed in patients with PSA < or =4.0 ng/ml. MRI-based PSA density of the prostate (PSAD) and of the prostatic transitional zone (PSAT) could improve differentiation of PCA and benign prostatic hyperplasia.

MATERIAL AND METHODS

Total prostate and transitional zone volumes were planimetrically determined in axial, T2-weighted fast spin echo MR images of the prostate. Serum PSA concentration was measured with an automated standardized microparticle enzyme immune assay. PSAD and PSAT were calculated in 17 patients with clinically significant PCA and 42 patients with benign prostatic hypertrophy (BPH) (66 +/- 6 versus 64 +/- 8 years, p = 0.2410, t test) who had PSA levels < or =10.0 ng/ml.

RESULTS

For differentiation of BPH and PCA, PSA alone above the optimal cutoff level of 4.2 ng/ml showed an odds ratio for PCA of 6.7 (95% confidence interval [CI], 1.9-23.2). PSAD showed an odds ratio for PCA of 71.3 (95% CI, 11.8-430.9) above the optimal cutoff level of 0.07 ng/ml/cc. PSAT demonstrated an odds ratio for PCA of 320.0 (95% CI, 27.1-3781.4) above the optimal cutoff level of 0.15 ng/ml/cc.

CONCLUSIONS

In patients with PSA < or =10.0 ng/ml, MRI-based PSAD and PSAT appear to improve differentiation of prostate cancer and BPH and are feasible to reduce the frequency of unnecessary prostate biopsy.

Expression of endothelin receptor a associated with prostate cancer progression

PURPOSE

We determined the role of endothelin receptors in prostate cancer progression.

MATERIALS AND METHODS

We examined 51 prostate cancer specimens obtained at surgery or biopsy for the relationship of endothelin receptor expression determined by immunohistochemical staining with malignant potential.

RESULTS

The positive staining rate of endothelin receptor A in the 51 specimens was significantly higher than of endothelin B (71% versus 24%, p <0.0001). The staining rate of receptor A in Gleason score 5 to 10 disease was significantly higher than in Gleason 2 to 4 disease (91% versus 29%, p <0.0001). The overall staining rate of endothelin receptor A in nonorgan confined disease without bone metastasis but with extraprostatic disease was 87% in 23 cases, including 16 of 19 stage T3 (84%) and all 4 stage T4 (100%) cases. This rate was significantly higher than that of organ confined cancer (29%, p = 0.0003). All patients with bone metastasis had positive staining for endothelin receptor A. An especially high rate of intensely positive staining was observed for endothelin receptor A in biopsy specimens with bone metastasis or Gleason sum 8 to 10. Moreover, positive staining was stronger in cancer cells penetrating the prostatic capsule than in those at the primary foci. However, the positive staining rate of endothelin receptor B was not significantly different in organ and nonorgan confined cancer without bone metastasis (12% versus 26%, p = 0.4284), bone metastatic and nonmetastatic cancer (20% versus 36%, p = 0.2619) or the Gleason sum groups (p = 0.0874).

CONCLUSIONS

Our results indicate that endothelin receptor A expression may serve as a marker for and have an important role in prostate cancer progression.

Prostate specific antigen adjusted for transition zone volume: the most powerful method for detecting prostate carcinoma

BACKGROUND

Several methods for the identification of patients with prostate carcinoma have been proposed to enhance the clinical usefulness of prostate specific antigen (PSA). However, it remains unclear which method is superior in practical use. The authors attempted prospectively to identify the most powerful method with which to detect prostate carcinoma, especially among patients with intermediate PSA levels.

METHODS

Between October 1997 and August 1999, systematic sextant biopsies were performed on 281 patients, including 147 with PSA levels between 4.1 ng/mL and 10.0 ng/mL. The clinical values of PSA, the free PSA to total PSA ratio (free/total PSA ratio), alpha-1-antichymotrypsin-PSA complex (PSA-ACT), the calculated derivatives, PSA density (PSAD), and PSA density of the transition zone (PSATZD) for the detection of prostate carcinoma were compared by using receiver operating characteristic (ROC) curves and logistic regression analyses.

RESULTS

According to ROC curve analysis, PSATZD had the greatest area under the curve in the overall patient population and in patients with intermediate PSA levels. In patients with intermediate PSA levels, at the sensitivity of 90%, PSATZD would have prevented unnecessary biopsies in 68 of 117 patients who were without prostate carcinoma, whereas PSA, free/total PSA ratio, and PSA-ACT would have prevented unnecessary biopsies in 25, 28, and 25 patients, respectively. Stepwise logistic regression analysis showed that PSATZD and findings on digital rectal examination were significant independent predictors.

CONCLUSIONS

PSATZD had the most useful validity in the differentiation between prostate carcinoma and benign prostatic enlargement in the overall patient population and in patients with intermediate PSA levels.

Prospective evaluation of prostate cancer detection by prostate-specific antigen-related parameters

BACKGROUND

The diagnostic value of prostate-specific antigen (PSA) for differentiating prostate cancer from benign prostatic conditions is limited by its lack of specificity. Several PSA-related parameters have been suggested as enhancing the discriminatory power of total PSA values, but their clinical utility should be considered preliminary until established in a prospectively evaluated cohort.

METHODS

In a prospective cohort study, results of ultrasound-guided biopsy and/or transurethral resection of the prostate gland were assessed in 706 consecutive Japanese men. The clinical usefulness of total PSA, free PSA, percentage of free PSA, PSA density (PSAD), PSA density for transition zone (PSADT) and gland volume for predicting prostate cancer was investigated using receiver operating characteristic (ROC) curve analysis in 16 different patient subgroups.

RESULTS

Overall, 150 of the 706 patients (21.2%) had prostate carcinoma. The ROC curve analysis showed that PSAD and PSADT were more powerful predictors of prostate cancer than total PSA in most of the 16 patient subgroups tested. The improvement in performance was modest, however. No substantial difference was noted between PSAD and PSADT. Total gland volume did not significantly affect the performance of these parameters. The use of a PSAD threshold value of 0.11-10.15 ng/mL per cm3 (or a PSADT value of 0.23-0.27 ng/mL per cm3) would have avoided 24-48% (or, for PSADT, 34-40%) of unnecessary biopsies at the cost of missing 5-10% of detectable cancers in a patient subgroup with intermediate total PSA levels. The performance of free PSA and percentage of free PSA was worse than that of any other test in this study. This may be due to inappropriate handling of sera prior to measurement.

CONCLUSIONS

The discriminatory potential of total PSA for predicting prostate cancer was modestly improved by the use of PSAD and PSADT. No substantial advantage of PSADT over PSAD could be demonstrated. Stringent and standardized storage conditions should always be maintained when applying free PSA-related parameters.

Predicting the extent of prostate cancer using the combination of systematic biopsy and serum prostate-specific antigen in Japanese men

OBJECTIVE

To determine the utility of systematic biopsy alone or combined with an assay of serum prostate-specific antigen (PSA) level to predict the extent of prostate cancer in Japanese men.

PATIENTS AND METHODS

Thirty-two patients who were diagnosed as having clinically organ-confined prostate cancer and who underwent prostatectomy were evaluated retrospectively for the results of systematic biopsy (percentage of positive biopsy cores and cancer location), serum PSA and the pathological stage of whole-mount sections of the prostatectomy specimens.

RESULTS

The incidence of extraprostatic disease (pT3N0M0 or N+) in patients with >/= 8 ng/mL of serum PSA and cancer in bilateral lobes was significantly higher than in those with <8 ng/mL PSA and cancer in one lobe (83% vs 30%, P=0.020). In those with more than half the biopsy cores positive, extraprostatic disease was significantly more common than in those with less than half positive (93% vs 44%, P=0.0075); moreover, in patients with more than half the cores positive and >/= 8 ng/mL serum PSA, it was significantly more common than in those with less than half positive and <8 ng/mL of serum PSA (93% vs 27%, P=0.0021). However, the incidence of extraprostatic disease predicted by three variables (cancer location, percentage positive biopsy cores and serum PSA) was not significantly better than that predicted by two variables (percentage positive cores and serum PSA).

CONCLUSIONS

The combination of systematic biopsy and serum PSA may be useful in predicting extraprostatic cancer. Patients with >/= 8 ng/mL serum PSA and more than half the biopsy cores positive could avoid a prostatectomy because there is a high probability that they have extraprostatic disease.

Comparison of prostate-specific antigen corrected for total prostate volume and transition zone volume in a population-based screening study

OBJECTIVES

To compare the discriminatory potential between prostate cancer and benign conditions of the prostate in a population-based screening study, of serum prostate-specific antigen levels (PSA) and PSA corrected for both the total prostate volume (PSA-D) and the transition zone volume (PSA-T).

METHODS

In a randomized population-based screening study (Rotterdam section of the European Randomized Study of Screening for Prostate Cancer), in which 10,865 men have been screened, the biopsy results of 1202 men with PSA levels of 4 ng/mL or more were evaluated. Planimetric and prolate ellipsoid volumes of the total prostate as well as of the transition zone were measured. The measured volumes were compared with the volumes of 57 radical prostatectomy specimens through Spearman's rank correlation coefficient and agreement tests. A receiver operating characteristic (ROC) curve analysis was done of sensitivity and specificity of biopsy indications through PSA and PSA corrected for the volumes measured with transrectal ultrasound.

RESULTS

In the 1202 men studied, 361 cases of prostate cancer were diagnosed. Both PSA-D and PSA-T showed a significantly higher area under the ROC curve (0.77 and 0.79, respectively) than PSA alone (area 0.65). There was no significant difference between PSA-D and PSA-T. The use of a PSA-D threshold value of 0. 10 ng/mL/cc would have avoided 28% of biopsies at the cost of 10% of detectable cancers. A PSA-D threshold of 0.15 ng/mL/cc would have avoided 73.8% of biopsies at the cost of not diagnosing 43.8% of detectable cancers.

CONCLUSIONS

The planimetrically obtained prostate volume showed a more favorable agreement with the radical prostatectomy volume than the prolate ellipsoid volume. The discriminatory potential of the corrected PSA value is better at predicting the results of needle biopsy of the prostate when compared with PSA alone. The use of the transition zone volume for this correction results in a higher discriminatory potential when compared to the use of the total prostate volume; however, the observed difference was not statistically significant.

The utility of free to total PSA ratio for detecting prostate cancer in Japanese men with total PSA between 2.1 and 10 ng/ml

We sought to determine whether the free to total prostate specific antigen (PSA) ratio in men with "gray zone" total PSA could accurately indicate the presence or absence of cancer, thus reducing the number of unnecessary biopsies without lessening the chance of detecting early stage prostate cancers. In 137 patients with total PSA levels between 2.1 and 10.0 ng/ml, we examined total PSA, free to total PSA ratio, PSA density (PSAD), and prostatic volume measured by transrectal ultrasound, and used these features to predict histologic features determined following sextant biopsy and/or surgery of the prostate. Of 137 patients with intermediate PSA levels, 25 (18%) had cancer. With a free to total PSA cut-off of 20%, cancer would not have been detected in 4 of the 25 patients (84% sensitivity), and 36% of the unnecessary negative biopsies would have been successfully avoided (p < 0.0005). With a PSAD cut-off of 0.15, cancer would have been missed in 4 of the 25 patients (84% sensitivity) and a 50% reduction in unnecessary negative biopsies would have been possible (p < 0.0005). Of 41 patients with large prostatic glands (>40 cm(3)), cancer was detected in only one, compared with 24 (25%) of 96 patients with small glands (<40 cm(3)) (p = 0.002). The results of receiver operating characteristic analysis indicated that PSAD, free to total PSA ratio, and prostatic volume would be effectively applicable to the diagnosis of cancer (areas under the curve: 0.7562, 0.7564, and 0.7693, respectively). At 100% sensitivity, specificity was highest for PSAD used in conjunction with ratio of free to total PSA. All patients with cancer had PSAD > 0.15 and/or free to total PSA < 15%. Patients with PSAD < 0.15 and free to total PSA ratio > 15% had no cancer (p < 0.0001). By this procedure, a 48% (54 of 112) reduction in the number of unnecessary biopsies would have been possible. Use of the free to total PSA ratio, measured with the AxSYM system, can significantly reduce unnecessary negative biopsies in patients with intermediate levels of PSA. Prostatic volume data can enhance the usefulness of this ratio for diagnosing prostate cancer.

Serum matrix metalloproteinase-2 and its density in men with prostate cancer as a new predictor of disease extension

We examined whether the serum matrix metalloproteinase-2 (MMP-2) level and MMP-2 density could be predictors of the development and extension of prostate cancer. Serum samples were collected before any clinical treatment from 98 patients with prostate cancer and from 76 patients with benign prostatic hyperplasia (BPH). Control sera were obtained from 70 healthy men. The serum level of MMP-2 was determined by 1-step enzyme immunoassay. A newly defined MMP-2 density parameter was determined by dividing the serum level of MMP-2 by the prostate volume, which was measured by ultrasonography. The mean serum level of MMP-2 in prostate cancer patients was significantly higher than in the control and BPH groups. Furthermore, the serum MMP-2 levels in prostate cancer patients with metastasis were highly elevated compared with those without metastases. The MMP-2 density in pathologically organ-confined prostate cancer was significantly higher than that in BPH. There was a statistically significant difference in the MMP-2 density between pT2N0M0 and pT1N0M0 prostate cancers. Moreover, the serum MMP-2 level correlated well with the clinical course of prostate cancer with bone metastasis. Our results suggest that MMP-2 plays an important role in the development and extension of prostate cancer and that the serum level of MMP-2 and the MMP-2 density indicate prostate cancer extension and are, therefore, useful for the followup of prostate cancer patients.