Prostate cancer: transrectal ultrasound and pathology comparison. A preliminary study of outer gland (peripheral and central zones) and inner gland (transition zone) cancer

Clinicopathologic Significance of Anterior Prostate Cancer: Comparison With Posterior Prostate Cancer in the Era of Multiparametric Magnetic Resonance Imaging

Anterior prostate cancer (APC) has been considered an indolent tumor, most commonly arising in the transition zone (TZ). More recently, detection of APC has been facilitated through multiparametric magnetic resonance imaging and improved biopsy techniques, enabling earlier detection. The pathologic features and clinical significance of pure APC in a large contemporary series of well-characterized tumors have, to date, not been elucidated. Cases with APC defined as cancer present anterior to the urethra only were identified from 1761 consecutive radical prostatectomy specimens accessioned between January 2015 and August 2016. The clinicopathologic features of these cases were compared with those of pure posterior prostate cancer (PPC) and the features of anterior peripheral zone (APZ) cancers were compared with those of TZ cancers. In addition, the tumor series from 2015 to 2016 was compared with a cohort of 1054 patients accessioned before the utilization of multiparametric magnetic resonance imaging in the routine workup of patients with prostate cancer. In the 2015-2016 series, there were 188 (10.7%) patients with APC compared with 5.4% in the series from the pre-multiparametric magnetic resonance imaging era. No difference was observed between APC and PPC with regards to patient age or mean serum prostate-specific antigen at presentation. Mean tumor volume and positive surgical margin (PSM) rates were significantly higher in APC. In contrast, PPC was more commonly high grade with more frequent extraprostatic extension (EPE). None of the cases of APC had infiltration of the seminal vesicle or lymph node involvement, in contrast to PPC, with almost 14% of cases in each category. The 3- and 5-year biochemical recurrence-free survival was significantly higher in APC when compared with PPC, although this was not retained on multivariable analysis which included tumor location. On division of APCs according to anatomic zone of origin, 45% were APZ cancer and 37% TZ cancer. On comparison of APZ and TZ cancers, there were no significant differences in mean age and serum prostate-specific antigen at presentation as well as tumor volume, Gleason score, and PSM rate. High-grade malignancy (Gleason score >3 + 4=7) was seen in 26% of TZ cancers which compared with 44% of APZ cancers and 56% of PPC cancers. The rate of EPE was significantly higher in APZ when compared with TZ cancer ( P< 0.0005); however, the biochemical recurrence rate was not significantly different between the groups. The prevalence of APC in radical prostatectomy specimens has increased in recent times, in association with earlier detection at a stage amenable to curative surgical treatment. APC, when compared with PPC, is less commonly high grade with less frequent EPE, despite the APC group having larger tumors and a higher PSM rate at presentation. However, not all anterior cancers are indolent. Anterior cancers are more commonly seen in the APZ than the TZ and APZ cancers appear more locally aggressive than TZ cancers.

Comparison of a Personalized Prostate Biopsy Pattern With Traditional Transrectal Prostate Biopsy: Different Cancer Detection Rate

Background: In terms of prostate biopsy approaches, it is difficult to reach the ventral central region of the prostate with the traditional transrectal prostate biopsy, while with the transperineal biopsy, the tumor in the dorsolateral region of the prostate is easily missed. However, until now, no studies have investigated the biopsy accuracy in the selective application of transrectal or transperineal biopsies according to the lesion site.

Methods: We developed a personalized prostate biopsy pattern and the biopsy approach was selected individually according to the lesion site. We compared it with the traditional transrectal prostate biopsy method to evaluate the efficiency. Patients (n = 351) who underwent prostate biopsy at Qilu Hospital of Shandong University from January 2018 to October 2020 were divided into two groups, including the traditional transrectal prostate biopsy group (n = 236) and the personalized group (n = 115). The data from patients, including clinical characteristics, biopsy results, and complications, were analyzed.

Results: The clinical characteristics of the two groups were similar. The total detection rate of prostate cancer in the personalized group was 49.6%, which was significantly higher than 38.1% in the traditional group (p = 0.023). When prostate-specific antigen was &lt;20 ng/ml, the detection rates of the two groups were 30.4 and 19.3%, respectively (p = 0.039). The PI-RADS was positively associated with high-grade prostate cancer in the personalized group. Patients with complications in the traditional transrectal systematic method group accounted for 6.8%, and those in the personalized group complications through the transrectal and transperineal approaches accounted for 7.1 and 4.1%, respectively. The most common complications in the transrectal group were fever and rectal bleeding, and those in the transperineal group were hematuria and urinary retention.

Conclusion: Compared with traditional transrectal prostate biopsy, the personalized biopsy pattern improved the detection rate of prostate cancer. The complications of the transrectal approach were much higher than those in the transperineal approach.

Prostate zones and cancer: lost in transition?

Localized prostate cancer shows great clinical, genetic and environmental heterogeneity; however, prostate cancer treatment is currently guided solely by clinical staging, serum PSA levels and histology. Increasingly, the roles of differential genomics, multifocality and spatial distribution in tumorigenesis are being considered to further personalize treatment. The human prostate is divided into three zones based on its histological features: the peripheral zone (PZ), the transition zone (TZ) and the central zone (CZ). Each zone has variable prostate cancer incidence, prognosis and outcomes, with TZ prostate tumours having better clinical outcomes than PZ and CZ tumours. Molecular and cell biological studies can improve understanding of the unique molecular, genomic and zonal cell type features that underlie the differences in tumour progression and aggression between the zones. The unique biology of each zonal tumour type could help to guide individualized treatment and patient risk stratification.

Does index tumor predominant location influence prognostic factors in radical prostatectomies?

PURPOSE

To find any influence on prognostic factors of index tumor according to predominant location.

MATERIALS AND METHODS

Prostate surgical specimens from 499 patients submitted to radical retropubic prostatectomy were step-sectioned. Each transverse section was subdivided into 2 anterolateral and 2 posterolateral quadrants. Tumor extent was evaluated by a semi-quantitative point-count method. The index tumor (dominant nodule) was recorded as the maximal number of positive points of the most extensive tumor area from the quadrants and the predominant location was considered anterior (anterolateral quadrants), posterior (posterolateral quadrants), basal (quadrants in upper half of the prostate), apical (quadrants in lower half of the prostate), left (left quadrants) or right (right quadrants). Time to biochemical recurrence was analyzed by Kaplan-Meier product-limit analysis and prediction of shorter time to biochemical recurrence using univariate and multivariate Cox proportional hazards model.

RESULTS

Index tumors with predominant posterior location were significantly associated with higher total tumor extent, needle and radical prostatectomy Gleason score, positive lymph nodes and preoperative prostate-specific antigen. Index tumors with predominant basal location were significantly associated with higher preoperative prostate-specific antigen, pathological stage higher than pT2, extra-prostatic extension, and seminal vesicle invasion. Index tumors with predominant basal location were significantly associated with time to biochemical recurrence in Kaplan-Meier estimates and significantly predicted shorter time to biochemical recurrence on univariate analysis but not on multivariate analysis.

CONCLUSIONS

The study suggests that index tumor predominant location is associated with prognosis in radical prostatectomies, however, in multivariate analysis do not offer advantage over other well-established prognostic factors.

Innovations in diagnostic imaging of localized prostate cancer

PURPOSE

In recent years, various imaging modalities have been developed to improve diagnosis, staging, and localization of early-stage prostate cancer (PCa).

METHODS

A MEDLINE literature search of the time frame between 01/2007 and 06/2013 was performed on imaging of localized PCa.

RESULTS

Conventional transrectal ultrasound (TRUS) is mainly used to guide prostate biopsy. Contrast-enhanced ultrasound is based on the assumption that PCa tissue is hypervascularized and might be better identified after intravenous injection of a microbubble contrast agent. However, results on its additional value for cancer detection are controversial. Computer-based analysis of the transrectal ultrasound signal (C-TRUS) appears to detect cancer in a high rate of patients with previous biopsies. Real-time elastography seems to have higher sensitivity, specificity, and positive predictive value than conventional TRUS. However, the method still awaits prospective validation. The same is true for prostate histoscanning, an ultrasound-based method for tissue characterization. Currently, multiparametric MRI provides improved tissue visualization of the prostate, which may be helpful in the diagnosis and targeting of prostate lesions. However, most published series are small and suffer from variations in indication, methodology, quality, interpretation, and reporting.

CONCLUSIONS

Among ultrasound-based techniques, real-time elastography and C-TRUS seem the most promising techniques. Multiparametric MRI appears to have advantages over conventional T2-weighted MRI in the detection of PCa. Despite these promising results, currently, no recommendation for the routine use of these novel imaging techniques can be made. Prospective studies defining the value of various imaging modalities are urgently needed.

[Sonographic imaging of the prostate]

Accurate identification of the location of carcinoma in the prostate is essential for long-term therapeutic success, in particular for minimally invasive procedures. In recent years many new positive study results for prostate imaging have been reported which must be compared and evaluated and previous conservative assessments may need to be re-evaluated. In addition, combinations of different imaging techniques are increasingly being used in daily clinical routine. Due to technical advancements in sonographic imaging, such as elastography and contrast-enhanced ultrasound (CEUS), the detection rate of prostate cancer can be increased. An overview of the different imaging modalities and current literature are presented in this article.

Transrectal Ultrasound (US), Contrast-enhanced US, Real-time Elastography, HistoScanning, Magnetic Resonance Imaging (MRI), and MRI-US Fusion Biopsy in the Diagnosis of Prostate Cancer

CONTEXT

Debates on overdiagnosis and overtreatment of prostate cancer (PCa) are ongoing and there is still huge uncertainty regarding misclassification of prostate biopsy results. Several imaging techniques that have emerged in recent years could overcome over- and underdiagnosis in PCa.

OBJECTIVE

To review the literature on transrectal ultrasound (TRUS)-based techniques (contrast enhancement, HistoScanning, elastography) and magnetic resonance imaging (MRI)-based techniques for a nonsystematic overview of their benefits and limitations.

EVIDENCE ACQUISITION

A comprehensive search of the PubMed database between August 2004 and August 2014 was performed. Studies assessing grayscale TRUS, contrast-enhanced (CE)-TRUS, elastography, HistoScanning, multiparametric MRI (mpMRI), and MRI-TRUS fusion biopsy were included. Publications before 2004 were included if they reported the principle or the first clinical results for these techniques.

EVIDENCE SYNTHESIS

Grayscale TRUS alone cannot detect PCa foci (detection rate 23-29%). TRUS-based (elastography) and MRI-based techniques (MRI-TRUS fusion biopsy) have significantly improved PCa diagnostics, with sensitivity of 53-74% and specificity of 72-95%. HistoScanning does not provide convincing or homogeneous results (specificity 19-82%). CE-TRUS seems to be user dependent; it is used in a low number of high-volume centers and has wide ranges for sensitivity (54-79%) and specificity (42-95%). For all the techniques reviewed, prospective multicenter studies with consistent definitions are lacking.

CONCLUSIONS

Standard grayscale TRUS is unreliable for PCa detection. Among the techniques reviewed, mpMRI and MRI-TRUS fusion biopsy seem to be suitable for enhancing PCa diagnostics. Elastography shows promising results according to the literature. CE-TRUS yields very inhomogeneous results and might not be the ideal technique for clinical practice. The value of HistoScanning must be questioned according to the literature.

PATIENT SUMMARY

New imaging modalities such as elastography and magnetic resonance imaging/transrectal ultrasound fusion biopsies have improved the detection of prostate cancer. This may lower the burden of overtreatment as a result of more precise diagnosis.

Prostate volumes derived from MRI and volume-adjusted serum prostate-specific antigen: correlation with Gleason score of prostate cancer

OBJECTIVE

The purpose of this article is to study relationships between MRI-based prostate volume and volume-adjusted serum prostate-specific antigen (PSA) concentration estimates and prostate cancer Gleason score.

MATERIALS AND METHODS

The study included 61 patients with prostate cancer (average age, 63.3 years; range 52-75 years) who underwent MRI before prostatectomy. A semiautomated and MRI-based technique was used to estimate total and central gland prostate volumes, central gland volume fraction (central gland volume divided by total prostate volume), PSA density (PSAD; PSA divided by total prostate volume), and PSAD for the central gland (PSA divided by central gland volume). These MRI-based volume and volume-adjusted PSA estimates were compared with prostatectomy specimen weight and Gleason score by using Pearson (r) or Spearman (ρ) correlation coefficients.

RESULTS

The estimated total prostate volume showed a high correlation with reference standard volume (r = 0.94). Of the 61 patients, eight (13.1%) had a Gleason score of 6, 40 (65.6%) had a Gleason score of 7, seven (11.5%) had a Gleason score of 8, and six (9.8%) had a Gleason score of 9 for prostate cancer. The Gleason score was significantly correlated with central gland volume fraction (ρ = -0.42; p = 0.0007), PSAD (ρ = 0.46; p = 0.0002), and PSAD for the central gland (ρ = 0.55; p = 0.00001).

CONCLUSION

Central gland volume fraction, PSAD, and PSAD for the central gland estimated from MRI examinations show a modest but significant correlation with Gleason score and have the potential to contribute to personalized risk assessment for significant prostate cancer.

Classification of focal prostatic lesions on transrectal ultrasound (TRUS) and the accuracy of TRUS to diagnose prostate cancer

Objective

To improve the diagnostic efficacy of transrectal ultrasound (TRUS)-guided targeted prostatic biopsies, we have suggested the use of a new scoring system for the prediction of malignancies regarding the characteristics of focal suspicious lesions as depicted on TRUS.

Materials and Methods

A total of 350 consecutive patients with or without prostate cancer who underwent targeted biopsies for 358 lesions were included in the study. The data obtained from participants were randomized into two groups; the training set (n = 240) and the test set (n = 118). The characteristics of focal suspicious lesions were evaluated for the training set and the correlation between TRUS findings and the presence of a malignancy was analyzed. Multiple logistic regression analysis was used to identify variables capable of predicting prostatic cancer. A scoring system that used a 5-point scale for better malignancy prediction was determined from the training set. Positive predictive values for malignancy prediction and the diagnostic accuracy of the scored components with the use of receiver operating characteristic curve analysis were evaluated by test set analyses.

Results

Subsequent multiple logistic regression analysis determined that shape, margin irregularity, and vascularity were factors significantly and independently associated with the presence of a malignancy. Based on the use of the scoring system for malignancy prediction derived from the significant TRUS findings and the interactions of characteristics, a positive predictive value of 80% was achieved for a score of 4 when applied to the test set. The area under the receiver operating characteristic curve (AUC) for the overall lesion score was 0.81.

Conclusion

We have demonstrated that a scoring system for malignancy prediction developed for the characteristics of focal suspicious lesions as depicted on TRUS can help predict the outcome of TRUS-guided biopsies.

Transition Zone Prostate Cancers: Features, Detection, Localization, and Staging at Endorectal MR Imaging

PURPOSE

To retrospectively evaluate the accuracy of endorectal magnetic resonance (MR) imaging in the detection and local staging of transition zone prostate cancers, with pathologic analysis serving as the reference standard, and to assess MR imaging features of these cancers.

MATERIALS AND METHODS

The institutional review board approved this HIPAA-compliant retrospective study and waived the informed consent requirement. An institutional database of 986 patients who underwent MR imaging before radical prostatectomy yielded 148 consecutive patients with at least one transition zone cancer at step-section pathologic analysis. An additional 46 patients without transition zone cancer were randomly selected as a control group. Two readers independently reviewed MR studies to identify patients with transition zone cancers and determine the location and local extent of these cancers. Imaging features that helped in the identification of transition zone cancers were recorded. Descriptive and kappa statistics, as well as receiver operating characteristic and multivariate logistic regression analyses, were used.

RESULTS

For identification of patients with transition zone cancers, sensitivity and specificity were 75% and 87%, respectively, for reader 1 and 80% and 78%, respectively, for reader 2. Interreader agreement was fair. For detection of the location of transition zone cancer, the area under the receiver operating characteristic curve was 0.75 for reader 1 and 0.73 for reader 2. Interreader agreement was fair. The readers' accuracy in detecting transition zone cancer foci increased significantly (P=.001) as tumor volume increased. In the detection of extraprostatic extension of transition zone cancers, sensitivity and specificity were 56% and 94%, respectively, for reader 1 and 28% and 93%, respectively, for reader 2. Homogeneous low T2 signal intensity (P=.001 for reader 1, P<.001 for reader 2) and lenticular shape (P=.017 for reader 1) were significantly associated with the presence of transition zone cancer.

CONCLUSION

MR imaging can be used to detect, localize, and stage transition zone prostate cancers.

GEC/ESTRO-EAU recommendations on temporary brachytherapy using stepping sources for localised prostate cancer

BACKGROUND AND PURPOSE

The aim of this paper is to present the GEC/ESTRO-EAU recommendations for template and transrectal ultrasound (TRUS) guided transperineal temporary interstitial prostate brachytherapy using a high dose rate iridium-192 stepping source and a remote afterloading technique. Experts in prostate brachytherapy developed these recommendations on behalf of the GEC/ESTRO and of the EAU. The paper has been approved by both GEC/ESTRO steering committee members and EAU committee members.

PATIENTS AND METHODS

Interstitial brachytherapy (BT) to organ confined prostate cancer can be applied as a boost treatment in combination with external beam radiation therapy (EBRT) using a proper number of BT fractions in curative intent. Temporary transperineal BT alone or in combination with EBRT are feasible as a palliative/salvage treatment modality because of local recurrence, however, without large clinical experience. The use of temporary BT as a monotherapy is subject of ongoing clinical research.

RESULTS

Recommendations for pre-treatment investigations, patient selection, equipment and facilities, the clinical team, the implant procedure (treatment planning and needle implantation) dose and fractionation, reporting, management of side effects and follow-up are given.

CONCLUSIONS

These recommendations are intended to be technically and advisory in nature, but the ultimate responsibility for the medical decision rests with the treating physician. Although, this paper represents the consensus of an interdisciplinary group of experts, TRUS and template guided temporary transperineal interstitial implants in prostate cancer are a constantly evolving field and the recommendations are subject to modifications as new data become available.

Correlation between hypoechoic nodules on ultrasonography and benign hyperplasia in the prostatic outer gland

OBJECTIVE

The purpose of this investigation was to study the correlation between hypoechoic nodules detected on ultrasonography and benign hyperplasia in the prostatic outer gland (POG) diagnosed by transrectal ultrasonography (TRUS)-guided biopsies.

METHODS

The TRUS-guided biopsies were performed on 472 patients suspected of having prostate cancer. Specimens obtained by biopsies were independently assessed by pathologists at 3 hospitals.

RESULTS

The histologic results of 310 patients (65.68%) were benign. Focal hypoechoic nodules located in the POG were found in 240 patients (50.8%) on TRUS scans. Among them, in 22 patients (9.17% of the 240 patients with hypoechoic nodules), benign hyperplasia was found in focal hypoechoic nodules located in the POG. Focal nodules were seen as well circumscribed with an ovoid shape and smooth surface in 18 patients.

CONCLUSIONS

Benign hyperplasia may sometimes originate in the POG and may appear as a hypoechoic nodule, similar to the appearance of prostate cancer.

Role of transition zone sampling by TURP in patients with raised PSA and multiple negative transrectal ultrasound-guided prostatic biopsies

The purpose of the study was to determine the role of transurethral resection of the prostate (TURP) to detect prostate cancer in patients with consistently negative transrectal ultrasound-guided biopsies of the prostate. We retrospectively identified and analysed the patients who also had at least two sets of transrectal ultrasound guided sextant prostate biopsies before their TURP during the period between 1998 and 2002. A total of 14 such patients were identified and the outcome of TURP was analysed. Three patients were found to have cancer in the resected specimen (3/14 = 21%). All three cancers were significant (Gleason scores between 6 and 8) and required further treatment. In patients who have rising levels of prostate-specific antigen and who have had multiple negative peripheral zone biopsies, the presence of biologically important transition zone cancers needs to be considered. This can be detected by transurethral resection of the prostate that samples the transition zone of the prostate.

Comparison of the zones of the human prostate with the seminal vesicle: morphology, immunohistochemistry, and cell kinetics

BACKGROUND

The prostate contains three glandular zones (central, peripheral, transition) with widely differing susceptibilities to cancer and benign prostatic hyperplasia (BPH). Most of the prostate is derived from urogenital sinus, but the central zone may be derived from Wolffian duct, in common with the seminal vesicles (SV). The peripheral zone is the most frequent site of cancer and the transition zone is the almost exclusive site of BPH.

METHOD

We compared the histology and immunohistochemistry of the SV with those of the prostate zones in order to identify differences associated with susceptibility to disease or different embryological origins. Sections from the prostates of nine organ donors (aged 15-36) were stained for tissue-specific markers, antigens previously shown to stain differentially between the zones and markers of cell proliferation and cell death.

RESULTS

Neuroendocrine cells were absent from the SV and significantly fewer neuroendocrine cells were seen in the central zone compared to the peripheral zone. Most of the SV epithelium stained for lactoferrin, compared to approximately one-third of central zone and only 2% of peripheral zone epithelial cells. The proliferative index of the central zone was approximately 50% lower and the incidence of apoptotic cells approximately half that of the peripheral and transition zones.

CONCLUSIONS

The central zone has features in common with both the SV and the other zones of the prostate. The higher incidence of proliferative diseases in the transition and peripheral zones may be associated with the higher rate of cell turnover observed in these zones.

Trends in Reporting Gleason Score 1991 to 2001: Changes in the Pathologist's Practice

OBJECTIVE

The prostate specific antigen (PSA) era has been associated with a grade migration towards moderately-differentiated (Gleason 5-7) prostate cancer. We investigated whether changes in interpretation of the Gleason system could be a contributing factor by reviewing the Gleason scores for prostate cancer in our region.

PATIENTS AND METHODS

Records of patients with prostate cancer assigned a Gleason score between 1991-2001 were retrospectively reviewed. We analysed trends in Gleason score, method of diagnosis and age at diagnosis. Following this, 50 cases from the dataset were randomly selected (stratified to contain half Gleason 2-4 reports) and reviewed in a blinded manner by an uropathologist and given a new Gleason score.

RESULTS

2737 patients were diagnosed and given a Gleason score; 1484 by prostate biopsy (PB) and 1172 by transurethral resection of prostate (TURP). 273 radical prostatectomy (RP) specimens were received, although the results of pre-operative biopsies were available in only 192 of these patients. Over time, there was an increase in the proportion of patients with Gleason 5-7, and a significant decrease in reporting of Gleason 2-4 cancer (r2 = 0.81, p < 0.0001). In 1991, 24% of cancers were Gleason 2-4; in 2001 this had decreased to 2.4%. TURP was associated with more Gleason 2-4 reports (23%) compared with PB (13.2%) and RP (9.2%). On blinded review, all Gleason 2-4 reports were upgraded to Gleason 5-7 cancer (p < 0.001).

CONCLUSION

Over time, the proportion of Gleason 2-4 prostate cancer reported has significantly decreased. Our study suggests that a change in practice by the pathologist is a significant factor in this grade migration.

Valor diagnóstico de segundas biopsias prostáticas en varones de riesgo. estudio estratificado por valor de psa

OBJECTIVE

[corrected] To value the diagnostic yield of the second prostate biopsy (BP).

PATIENTS AND METHODS

To 116 males with BP previous to kindliness surrendered to 2 or more BP for sextants guided with ultrasounds (US). The criteria of inclusion were: BP previous suspicious (PIN), high PSA, TR or suspicious US.

RESULTS

The average time passed between the first and following biopsy was 13 +/- 11 months. 35 malignant and 4 premalignant ones were obtained in the second realized biopsies, which gives a diagnostic global yield of 33.6%. When we stratify for value of PSA, we obtain that with PSA <4 ng/ml the yield was 23%, for PSA 4-10 ng/ml the yield was 32% and for PSA >10 ng/ml of 34.6%.

CONCLUSION

The repetition of the serial biopsy of prostate in patients of risk, improves the diagnostic yield and eliminates the false negatives of prostate carcinoma.

Transition zone carcinoma of the prostate gland: a common indolent tumour type that occasionally manifests aggressive behaviour

AIMS

Tumours arising in the transition zone (TZ) of the prostate gland are often well differentiated and considered clinically unimportant. We have observed examples of high-grade TZ cancers that prompted this study.

METHODS

Review of 654 radical prostatectomy specimens previously assessed by systematic whole organ histology identified 187 (29%) TZ cancers of which 76 (11.6%) represented the index (main) tumour. These were compared with a volume-matched group of 76 peripheral zone (PZ) carcinomas.

RESULTS

Fifty-nine of 76 TZ index carcinomas had additional minor tumours mainly located in the PZ. Compared to PZ tumours of similar size, TZ tumours had significantly lower Gleason scores, less Gleason grade 4/5 and lower rates of capsular penetration and positive surgical margins. However, within this TZ tumour group, seven carcinomas had a major Gleason grade 4 or 5 component with high rates of capsular penetration (57%) and positive surgical margins (43%). Positive anterior and bladder neck margins were more common in TZ carcinoma than peripheral tumours and transperineal biopsy was the method of choice for TZ cancer diagnosis.

CONCLUSIONS

A subset of TZ carcinoma characterised by high tumour grade has a significant risk of extraprostatic spread, margin positivity and possible biochemical failure. We recommend transperineal prostate biopsy for TZ tumour diagnosis and histological sampling of the anterior TZ at radical prostatectomy, even if macroscopically normal, to detect patients at risk from aggressive TZ carcinoma.

Population Screening for Prostate Cancer and Emerging Concepts for Young Men

Prostate cancer is the most common malignancy in American men, accounting for > 29% of all diagnosed cancers and approximately 13% of all cancer deaths. Nearly 1 of every 6 men will be diagnosed with the disease at some time in their lives. In 2003 alone, an estimated 221000 men in the United States will be diagnosed with prostate cancer and > 28000 will die of the disease. An elevated level of prostate-specific antigen (PSA) is correlated with the presence of prostate cancer, and since 1989 we have been living in the "PSA era," in which the PSA screening test is widely used in clinical practice. This article summarizes what has been learned about the use of PSA screening, including the intricacies of free PSA, PSA doubling time, and various factors that may affect PSA and confound screening in young men. Although population-based screening for prostate cancer has yet to be definitively proven to affect disease-specific mortality, PSA testing is detecting cancers in younger men and at earlier stages of disease progression and, partly as a result, 5-year cancer-specific survival is increasing. Even though this lead-time effect may not translate into long-term improvement, these changes are very promising and are a necessary prerequisite to effective screening. For patients at high risk with a family history of the disease and for black men, a strategy consisting of an annual PSA blood test and digital rectal examination for men >or=40 years of age appears to be prudent. Use of age- and race-specific reference ranges for PSA based on sensitivity, or maximal cancer detection, is the most appropriate approach in this high-risk group. Specifically among black men 40-49 years of age, those with a PSA value > 2.0 ng/mL should consider further evaluation. Many men at low/average risk aged 40-49 years also request testing and it is reasonable to offer testing and risk assessment to these young men. The exact screening threshold for total PSA in these men is unknown, but 95% of these men will have a PSA < 2.5 ng/mL. Prostate-specific antigen velocity, percentage of free PSA, and perhaps complexed PSA may be used to help determine risk, but further study of young men is needed. In the future, a risk-stratified approach using molecular biomarkers and/or proteomics in young men is anticipated.

Pathologic features the urologist should expect on a prostate biopsy

In recent years, the pathological evaluation of prostate biopsy specimens has made great improvements in diagnostic accuracy and comprehensiveness. In this article, we review major pathological findings on prostate biopsy, their interpretation and reporting, as well as their clinical significance and utility. We discuss especially the clinically relevant histological features in either a positive or negative biopsy. We emphasize that both Gleason score and extent of cancer involvement in a needle core biopsy are important predictors of clinical outcome after either radical prostatectomy or radiation. Special issues regarding diagnosis and grading of minimal cancer on needle core biopsies are discussed. We also highlight the current standards on high-grade prostatic intraepithelial neoplasia and atypical small acinar proliferation on needle core biopsies. In summary, the pathology reports on needle biopsies are far beyond the simple presence or absence of cancer; they contain invaluable information to clinicians on patient management and counseling.

Three-dimensional grayscale ultrasound: evaluation of prostate cancer compared with benign prostatic hyperplasia

OBJECTIVES

To compare the accuracy of the detection, localization, and staging of prostate cancer using transrectal three-dimensional (3D) grayscale ultrasonography (3D-US) with conventional transrectal two-dimensional grayscale ultrasonography (2D-US).

METHODS

Fifty patients with clinical localized prostate cancer scheduled to undergo radical retropubic prostatectomy and 50 patients with clinical benign prostatic hyperplasia underwent transrectal ultrasound investigations (2D and 3D). The prostate images were retrospectively analyzed by two ultrasound experts unaware of the clinical findings. The images of the prostate cancer group were correlated with the whole-mount histologic specimens of the prostate.

RESULTS

All percentages are given for experts 1 and 2. The sensitivity, specificity, and accuracy for the detection of prostate cancer without considering the definitive localization of the tumor for 2D-US was 72% and 76%, 50% and 54%, and 63% and 64%, respectively; for 3D-US, the rates were 82% and 88%, 40% and 42%, and 61% and 65%. The sensitivity, specificity, and accuracy of the combination of 2D-US with 3D-US was 88% and 90%, 36% and 38%, and 62% and 64%, respectively. The sensitivity, specificity, and accuracy for the exact localization of the prostate tumor for 2D-US was 44% and 46%, 50% and 54%, and 47% and 50%, respectively; for 3D-US, they were 52% and 62%, 40% and 42%, and 46% and 52%. The staging of prostate cancer using 3D-US was correct in 49% (expert 1) and in 57% (expert 2) of patients. No difference was observed between 2D-US and 3D-US for accurate staging. Both experts judged the interpretation of 3D-US images as superior to that of 2D-US images.

CONCLUSIONS

Although 3D-US had statistically significant increased sensitivity in the detection of lesions and decreased specificity compared with 2D-US, 3D-US did not result in significant clinical improvement in the detection and staging of prostate cancer.

Prostate cancer histologic trends in the metropolitan Detroit area, 1982 to 1996

OBJECTIVES

One of the concerns regarding the widespread use of serum prostate-specific antigen (PSA) as a screening tool for prostate cancer is the possibility that it may detect latent or clinically insignificant cancers. One indicator of clinical importance is thought to be histologic grade, with clinically unimportant cancers more likely to be well differentiated and clinically important tumors more likely to be moderately or poorly differentiated.

METHODS

Data from the metropolitan Detroit population-based Surveillance, Epidemiology, and End Results Program were examined to determine trends in prostate cancer histologic grading before and after the introduction of PSA screening.

RESULTS

From 1989 through 1996, the most recent year for which data are available, a dramatic increase in the incidence of prostate cancer occurred in the Detroit area, corresponding to the routine use of PSA as a screening test for prostate cancer. Local stage cancer demonstrated the largest increase in incidence. The incidence of moderately differentiated cancers also rose substantially during the same period; the incidence of poorly differentiated tumors remained about the same, and the incidence of well differentiated tumors decreased. Coincident with the increasing proportion of moderately differentiated cancers was a significant increase in the proportion of prostate biopsies performed (P = 0.001).

CONCLUSIONS

These population-based data add important evidence that prostate cancers identified with PSA are more likely to be moderately than well differentiated. Additionally, if the definition of clinical significance depends on histopathologic grade, this finding could further be interpreted as evidence that PSA is more likely to detect clinically significant prostate cancer.

Impalpable invisible stage T1c prostate cancer: characteristics and clinical relevance in 100 radical prostatectomy specimens--a different view

PURPOSE

We analyzed 100 consecutive radical prostatectomy specimens to evaluate the extent and clinical relevance of the stage T1c cancers discovered.

MATERIALS AND METHODS

All cases were diagnosed by systematic prostatic puncture biopsies because of abnormal prostate specific antigen (PSA) or PSA density. Surgical specimens were examined with the whole organ multiple step-section technique (4 mm.) to identify primary tumor location (peripheral or transition zone cancer), tumor volume, tumor volume divided by prostate volume (percent tumor volume), Gleason score, pathological T stage and positive surgical margins. Tumors smaller than 0.5 cm.3 and without unfavorable pathology (Gleason score 7 or more, or positive surgical margins) were considered insignificant.

RESULTS

Median patient age, PSA, tumor volume and Gleason score were 64 years, 8.8 micrograms./l., 1.6 cm.3 and 6, respectively. Of the specimens 46 (46%) had transition zone cancer that was clinically undetectable due to anterior location, while peripheral zone cancers were small, diffuse, anterolateral or in large glands with low percent tumor volume. Transition zone cancer showed greater PSA, PSA density, tumor volume and percent tumor volume than peripheral zone cancer (p = 0.08, 0.03, 0.0002 and 0.0004, respectively), yet with similar Gleason score (p = 0.4). Of the tumors 34 (34%) were locally advanced (stage pT3 and/or positive surgical margins, mostly anterior in 16 transition zone cancers, and apical or posterolateral in 18 peripheral zone cancers), whereas 22 were insignificant (6 transition and 16 peripheral zone cancers). Prostatic puncture biopsies with a core cancer length of less than 3 mm. could have predicted 18 of 19 insignificant tumors but underestimated 13 (33%) and 6 (17%) significant transition and peripheral zone cancers.

CONCLUSIONS

The majority of our stage T1c tumors were significant with a distinguished high incidence of transition zone cancer. Therefore, they were large but occult. Transition zone cancer behaved differently than peripheral zone cancer, and warranted considerations during treatment of stage T1c prostate carcinoma.

Multiple transrectal ultrasound-guided biopsies for the detection of prostate cancer and determination of tumor volume, grade, and seminal vesicle invasion

A total of 251 men with suspected prostate cancer were examined by transrectal ultrasound (TRUS) in order to evaluate the usefulness of TRUS and core biopsies for the detection of prostate cancer and determination of tumor volume, grade, and seminal vesicle invasion (SVI). Biopsies targeting hypoechoic lesions were taken in combination with systematic biopsies obtained from six standardized locations. Bilateral seminal vesicle biopsies were obtained from 168 of the men. A total of 26 patients underwent surgery and a comparison between the results of the histopathological evaluation of core biopsies and the prostatectomy specimen was performed. A total of 137 cancers were detected. In 34 patients (25%) the tumors were diagnosed by systematic biopsies alone. Tumor volume as estimated by TRUS underestimated the volume when compared to a planimetric technique. Correlation between the two methods was not found by regression analysis. Systematic biopsies did not improve grading compared to the grading of prostatectomy specimens. A total of 24 SVIs were detected. Valuable information was obtained for the diagnosis of prostate cancer by taking systematic biopsies.

Ultrasound-guided high dose rate conformal brachytherapy boost in prostate cancer: treatment description and preliminary results of a phase I/II clinical trial

PURPOSE

To improve results for locally advanced prostate cancer, a prospective clinical trial of concurrent external beam irradiation and fractionated iridium-192 (Ir-192) high dose rate (HDR) conformal boost brachytherapy was initiated.

METHODS AND MATERIALS

Between November 1991 and February 1994, 99 implants were performed on 33 patients with prostatic adenocarcinoma at William Beaumont Hospital. Using AJCC staging criteria, 9 patients had T2b tumors, 17 patients had T2c tumors, and 7 patients had T3 disease. Patients were treated with (a) 45.6 Gy whole pelvis external irradiation and (b) three HDR fractions of 5.5 Gy each (18 patients) or 6 Gy each (15 patients) to the prostate. Transperineal needle implants using real-time ultrasound guidance with interactive on-line isodose distributions were performed on an outpatient basis during weeks 1, 2, and 3 of external irradiation. Acute toxicity was scored using the Radiation Therapy Oncology Group (RTOG) morbidity grading system.

RESULTS

This technique of concurrent external pelvic irradiation and conformal HDR brachytherapy was well tolerated. No significant intraoperative or perioperative complications occurred. Three patients (9%) experienced Grade 3 acute toxicity (two dysuria and one diarrhea). All toxicities were otherwise Grades 1 or 2 and were primarily as expected from pelvic external irradiation. Persistent implant-related toxicities included Grades 1-2 perineal pain (12%) and hematospermia (15%). Median follow-up time was 13 months. Serum prostatic-specific antigen (PSA) levels normalized in 91% of patients (29 out of 32) within 1-14 months (median 2.8 months) after irradiation. PSA levels were progressively decreasing in the other three patients at last measurement. Prospectively planned prostatic rebiopsies done at 18 months in the first 10 patients were negative in 9 out of 10 (90%).

CONCLUSIONS

Acute toxicity has been acceptable with this unique approach using conformal high dose rate Ir-192 boost brachytherapy with concurrent external irradiation. The initial tumor response as assessed by serial PSA measurement and rebiopsy is extremely encouraging. Dose escalation will proceed in accordance with the protocol guidelines. Further patient accrual and longer follow-up will allow comparison to other techniques.

Transrectal ultrasound in the evaluation of rhabdomyosarcoma involving the prostate

OBJECTIVE

To evaluate transrectal ultrasound as a means of diagnosis and of monitoring patients with rhabdomyosarcoma involving the prostate.

PATIENTS AND METHODS

Serial transrectal ultrasonography was utilized to evaluate prostatic rhabdomyosarcoma in three patients.

RESULTS

Unlike prostatic adenocarcinoma and transitional cell carcinoma involving the prostate, which are predominantly hypoechoic, the echogenicity of rhabdomyosarcoma is similar to that of the normal prostate. Transrectal ultrasound provided a simple means of monitoring prostate size and sampling tissue in these patients.

CONCLUSION

Transrectal ultrasound imaging can be useful in both diagnosis and evaluation of treatment response as well as provide easy access for biopsies in patients with rhabdomyosarcoma involving the prostate.

L'utilità del color doppler nella patologia prostatica: Nostra esperienza

The authors report their experience with color Doppler (CD), associated with endorectal US in the study of prostatic diseases. They examined 35 patients with benign prostatic hyperplasia, 27 with prostatitis, 21 with prostatic carcinoma and 5 young healthy volunteers. In the 35 cases of benign prostatic hyperplasia, CD proved to be of limited usefulness, although ruling out concurrent, inflammatory or neoplastic disease. In the 27 cases of prostatitis, CD proved to be particulary useful in acute or chronic recurrent cases. In those cases the method showed marked color increase at the periurethral site or in the area close to the seminal vesicles, also allowing follow-up after therapy. In the 21 patients with prostatic carcinoma, CD allowed the demonstration of 2 tumours that were isoechoic at endorectal US with grey scale. In both cases it was possible to make a “color guided” biopsy.

Staging of prostate cancer

The clinical and pathologic staging of prostate cancer involves determination of the anatomic extent and burden of tumor based on the best available data. Two major classification schemes are currently used: the modified American system and the TNM system [primary tumor (T), regional lymph node (N), and metastases (M)]. Both systems stratify patients according to the method of tumor detection, separating nonpalpable "incidental" prostate cancers detected during transurethral resection for clinically benign prostatic hyperplasia (BPH) and palpable cancers detected by digital rectal examination. These staging systems also recognize nonpalpable tumors detected by an elevated serum prostate-specific antigen (PSA) level or an abnormal transrectal ultrasound image. Current staging is limited by a significant level of clinical understaging (up to 59%, in our experience) and overstaging (up to 5%) according to comparison with pathologic examination of resected specimens. Proposed improvements in staging include preoperative systematic sextant biopsies to assess tumor volume, volume-based prognostic index, and a multiple prognostic index. In this report, we evaluate the current aspects of clinical and pathologic staging of prostate cancer with emphasis on the early stages in which there is the greatest chance of cure.

Developmental estrogenization and prostatic neoplasia

The association of estrogens with benign prostatic hyperplasia and prostatic cancer has been widely studied, but no conclusive evidence exists for a role of estrogens in prostatic disease. This paper reviews the literature and describes studies which have sought to show a correlation of estrogens and alterations in the prostates of humans and experimental animal models. Using the developmentally estrogenized mouse model, we propose an alternative role for estrogens as a predisposing factor for prostatic diseases: estrogen exposure during development may initiate cellular changes in the prostate which would require estrogens and/or androgens later in life for promotion to hyperplasia or neoplasia. Thus, the critical time for estrogen action would be during the development of the prostatic tissue. We further suggest that estrogen-sensitive cells may remain in the prostate and be more responsive to estrogens later in life or less responsive to the normal controlling mechanisms of prostatic growth.

Staging of early prostate cancer: a proposed tumor volume-based prognostic index

Current staging of early prostate cancer separates patients into two groups: those with palpable and non-palpable tumors. Such staging relies on digital rectal examination in making this separation, despite the low sensitivity, low specificity, and low positive predictive value of this method. As an alternative, tumor volume may be useful for staging because of its powerful prognostic ability and its potential to be assessed clinically due to recent advances in imaging techniques such as transrectal ultrasound. In this study, we evaluate the utility of tumor volume in predicting progression of early prostate cancer based on the composite published evidence from nine pathologic studies of serially-sectioned prostates. Logistic regression revealed that tumor volume was a good positive predictor of all measures of tumor progression. There was a 10 percent probability of capsular invasion in tumors measuring about 0.5 cm3; 10 percent probability of seminal vesicle invasion in tumors measuring about 4.0 cm3; and 10 percent probability of metastases in tumors measuring about 5.0 cm3. These composite results suggest that tumor volume is a significant predictor of cancer progression. A volume-based prognostic index is proposed as an adjunct to staging for early prostate cancer.

Critical assessment of prostate cancer staging

Staging of prostatic adenocarcinoma is a systematic classification of the extent of disease based on clinical and pathologic criteria. This classification determines treatment and reflects ultimate expected clinical outcome. The technologic changes in diagnostic modalities need to be incorporated into the staging classification and a better assessment of biologic hazard of each individual tumor needs to be developed to further refine current treatment of prostate cancer.

The association of benign prostatic hyperplasia and cancer of the prostate

There are a number of similarities between benign prostatic hyperplasia (BPH) and cancer. Both display a parallel increase in prevalence with patient age according to autopsy studies (86.2% and 43.6%, respectively, by the ninth decade), although cancer lags by 15-20 years. Both require androgens for growth and development, and both respond to antiandrogen treatment regimens. Most cancers arise in prostates with concomitant BPH (83.3%), and cancer is found incidentally in a significant number of transurethral prostatectomy (TURP) specimens (10%). The clinical incidence of cancer arising in patients with surgically treated BPH is approximately 3%. BPH may be related to a subset of prostate cancer which arises in the transition zone, perhaps in association with atypical adenomatous hyperplasia (AAH). It is important to exclude cancer in patients presenting with symptoms of bladder outlet obstruction presumably due to BPH. For such patients, we recommend digital rectal examination (DRE) and, at least in high-risk patients, serum prostate specific antigen (PSA) determination. Transrectal ultrasound (TRUS) should be employed in patients with elevated PSA levels to determine the volume of the prostate, the relative contribution of BPH to volume, and the PSA density (ratio of PSA level to volume). Biopsy should be obtained from any area suspicious for cancer. Early detection and treatment of cancer when it is localized offers the greatest chance for cure.

Predicted prostate specific antigen results using transrectal ultrasound gland volume. Differentiation of benign prostatic hyperplasia and prostate cancer

METHODS

The diagnostic performance of transrectal ultrasound (TRUS) gland volume and prostate specific antigen (PSA) results were evaluated in 204 men consecutively scheduled to undergo transurethral prostatic resection (TUR).

RESULTS

Nonpalpable prostate cancer was detected by TRUS alone in 18% (29 of 161) and by TUR alone in 9% (14/161), for an overall cancer incidence of 27%. A predicted PSA value (TRUS gland volume x 0.20 ng/ml/g = polyclonal PSA) was used for comparison with serum PSA for each patient. TRUS positive predictive value improved from 52% to 86% when serum PSA exceeded the predicted value. The specificity and positive predictive value of PSA at 2.5 ng/ml were 23% and 37%, respectively, which increased to 88% and 72%, respectively, when serum PSA exceeded the predicted value.

CONCLUSIONS

Predicted PSA values produce decision levels near the 95th percentile for each patient and assist individual biopsy decisions better than grouped gland volume ranges. Wider application of TRUS and PSA in any clinical setting or early detection program is now possible.

Histologic changes of irradiated prostatic carcinoma diagnosed by transrectal ultrasound

Digital rectal examination and transrectal ultrasound was used to evaluate the clinical status of 125 men previously treated for prostate carcinoma by definitive radiation. Transrectal ultrasound-guided biopsy of a hypoechoic lesion was performed on all 125 men, with 71.2% of them found to have persistent carcinoma. These irradiated carcinomas exhibited increased tumor aggressiveness by both histologic (Gleason score) and biologic (DNA ploidy) parameters. Following radiation therapy 30.6% of pretreatment diploid tumors were found to be aneuploid after treatment. Similarly, there was a 24% increase in the number of poorly differentiated (Gleason score 8 to 10) tumors following radiation therapy. A number of patients with persistent carcinoma postradiation therapy, but with clinically localized disease, may be "cured" by subsequent surgery. Salvage radical prostatectomy found localized cancer in 16 of 20 patients (80%). The use of transrectal ultrasound for early detection and staging was crucial for patient selection for definitive salvage therapy.

Validity of Transrectal Ultrasonography in the Early Diagnosis and Staging of Prostatic Cancer

In 3 years of mass screening for early diagnosis of prostatic cancer, 57 tumors were found (57/5000, for a detection rate of 1.2%). Patients first underwent digital rectal examination (DRE): at present the least expensive, least invasive and most effective way to diagnose prostatic cancer. 420 men underwent transrectal ultrasonography (TRUS) with a 5 MHz transverse and longitudinal transducer for pathological digital rectal findings, obstructive symptoms and other reasons. Prostatic biopsy was performed in 190 patients with DRE findings and/or hypoechoic zones of the prostatic gland (transrectal digitally directed or ultrasonically perineal guided biopsies). The specificity, sensitivity and prediction capacity of DRE and TRUS in this group of patients was evaluated. Sensitivity of DRE was 92%, specificity 42% (usual finding for mass screening); predictive positive value was 41 %, negative 93%. Sensitivity of TRUS was 77%, specificity 57%, predictive positive value was 44%, negative 86%. Data seem to confirm the ability of TRUS to reduce the number of “false positives” after DRE (and consequently the number of biopsies). However, contraindications for use in mass screenings are: sensitivity lower than with DRE, high false positive rate and prohibitive cost for systematic use. Validity of TRUS is confirmed in clinical staging for the selection of patients undergoing radical retropubic prostatectomy, by comparison with local pathological staging.

Transrectal Ultrasound Imaging and Ultrasound Guided Prostate Biopsies in the Detection of Residual Carcinoma in Clinical Stage A Carcinoma of the Prostate

Planning treatment for patients diagnosed with stage A prostate cancer by transurethral resection or open enucleation can be difficult. Inability to determine the presence or absence of significant residual disease can result in unnecessary treatment for some individuals and inadequate treatment in others. Transrectal ultrasound imaging and systematic prostate biopsies offer a potential means of evaluating these patients. To determine the rate of residual cancer detection 3 groups of stage A prostate cancer cases were evaluated. Group 1 consisted of 39 patients who underwent radical prostatectomy. Preoperative ultrasound imaging revealed residual cancer in only 24%. Transrectal ultrasound guided systematic biopsies were performed in group 2 (25 patients) and revealed cancer in only 28%. Based on prior morphometric studies of prostatectomy specimens from stage A cases, a modification of the systematic biopsy method, which included anteriorly directed biopsies, was developed and applied to group 3 (47 patients). Cancer was detected in 47% of the patients, and it was detected by additional anterior biopsies alone in 11%.

To screen or not to screen?

This paper aims to present a case for screening for prostate cancer, though medical committees from many countries have recently decided against it. It is clear that prostate cancer fails many of the criteria for an effective screening program. There is certainly no single test that can be used reliably to detect prostate cancer. All the available tests have advantages and disadvantages. The sensitivities of the three widely used screening tests--digital rectal examination (DRE), prostate specific antigen (PSA), and transrectal ultrasound (TRUS)--vary from 50% to 85% in a number of studies, but the positive predictive value fluctuates around 30%. The use of all three tests must improve the detection rate. The European Cancer Programme is funding a pilot study in Antwerp and Rotterdam on screening for prostatic diseases. In Rotterdam, a pre-screen PSA is performed and then patients are randomized to no screening or DRE with TRUS. The Antwerp section of the study includes screening for benign prostatic hyperplasia and employs a questionnaire on urinary symptoms as a pre-screen test. Patients are then randomized to controls or DRE with TRUS and, if results are suspicious, PSA measurement. It will be about 8 years before it becomes clear whether there is a resulting drop in mortality from prostate cancer.

Clinical staging of prostatic carcinoma by prostatic mapping

The exact preoperative stage of prostatic cancer is the major problem involved in the indications for radical retropubic prostatectomy. A personal technique of prostatic mapping (PM) by means of strategic transrectal ultrasound guided core biopsies is presented as an effort to improve the staging of clinically localized prostatic cancer. PM is able “to photograph” intraprostatic neoplastic spread revealing infiltration of the apex and of the seminal vesicle beaks. Our hope is that, if our results are confirmed, PM will become an important tool in preoperative prostatic cancer staging.