Clinical significance of high-grade prostatic intraepithelial neoplasia in transurethral resection specimens

PCA3 and TMPRSS2: ERG Urine Level as Diagnostic Biomarker of Prostate Cancer

Background

Prostate cancer is a highly prevalent urological carcinoma with an increasing incidence in Indonesia and all around the world. Early diagnosis can greatly affect treatment outcomes and increase life expectancy. Several biomarkers for detecting prostate cancer have been studied and showed great promise.

Purpose

This study aims to analyze prostate cancer antigen 3 (PCA3) as well as transmembrane serine protease 2:ERG (TMPRSS2:ERG) for diagnosing and serving as urine biomarkers in predicting prostate cancer incidences.

Methods

We conducted an analytical study to assess the utility of PCA3 and TMPRSS2:ERG for detecting prostate cancer. Thirty samples were included in this study to see the utilization of PCA3 and TMPRSS2:ERG as diagnostic biomarkers of prostate cancer. A urine sample was taken and the PCA3 test was performed using the PCA3 PROGENSA test, while the TMPRSS2:ERG was performed using the chemiluminescent DNA probe method with a hybridization protection test.

Results

The average age of the subject was 61.07±8.3 years. Based on calculations using the Mann-Whitney test, there was a significant relationship between prostate-Specific Antigen (PSA) overexpression (p<0.001), TMPRSS2:ERG (p=0.001), and PCA3 (p=0.003) with prostate cancer incidence. The sensitivity of PCA3 and TMPRSS2:ERG in detecting prostate cancer was 76.9% and 92.3%, respectively. Hence, TMPRSS2:ERG and PCA3 can be used as biomarkers for the occurrence of prostate cancer. We also performed a Kruskal-Wallis test; however, there was no significant relationship between PSA (p=0.236), TMPRSS2:ERG (p=0.801), and PCA3 (p=0.091) with the Gleason score.

Conclusion

There is a significant correlation between overexpression of PSA, TMPRSS2:ERG and PCA3 with the incidence of prostate cancer, and TMPRSS2:ERG and PCA3 can be used as biomarkers of prostate cancer.

ERG expression in intraductal carcinoma of the prostate: comparison with adjacent invasive prostatic adenocarcinoma

Intraductal carcinoma of the prostate is a growth pattern of prostatic adenocarcinoma that has not been well characterized from the molecular standpoint. It remains debatable whether intraductal carcinoma of the prostate represents colonization of benign glands by pre-existing conventional prostatic adenocarcinoma, or progression of high-grade prostatic intraepithelial neoplasia. TMPRSS2-ERG is the most common gene fusion in conventional prostatic adenocarcinoma, identified in about 40-70% of cases. In this study, we compared the expression of ERG in intraductal carcinoma of the prostate and adjacent conventional prostatic adenocarcinoma. Thirty-one confirmed cases of intraductal carcinoma of the prostate, with adjacent conventional prostatic adenocarcinoma and available tissue blocks, were identified at our institution. Immunohistochemical stains were performed for ERG using a rabbit anti-ERG monoclonal antibody. The ERG expression in the intraductal carcinoma of the prostate component was compared with that in the adjacent conventional prostatic adenocarcinoma. Mean patient age was 65 years (range: 48-79 years). Positive ERG expression was identified in 11/31 (35%) cases of intraductal carcinoma of the prostate. In all 11/11 (100%) cases with positive ERG expression in the intraductal carcinoma of the prostate component, ERG expression was also positive in the adjacent conventional prostatic adenocarcinoma. In the 20/31 cases with negative ERG expression in the intraductal carcinoma of the prostate component, ERG was also negative in the adjacent conventional prostatic adenocarcinoma. It is highly conceivable that based on the identical ERG expression (positive or negative) in intraductal carcinoma of the prostate and the adjacent conventional prostatic adenocarcinoma, intraductal carcinoma of the prostate most likely represents colonization of benign glands by adjacent pre-existing conventional prostatic adenocarcinoma.

[Comparative study of histological results between resection and biopsy of the prostate]

PURPOSE

To evaluate the histological correlation between transuretral resection chips and biopsy cores within a population of patients who underwent resection of prostate (TURP) and prostate biopsies (BPx).

PATIENTS AND METHODS

Clinical and tumoral data of 77 patients who had both procedures simultaneously or with a slight delay were collected. According to the presence of prostate cancer (Pca), 4 groups were defined: group 1 (TURP and BPx negative), group 2 (TURP positive, BPx negative), group 3 (TURP negative, BPx positive), group 4 (TURP and BPx positive). Means and proportions were compared using Anova and χ(2) test, respectively.

RESULTS

The patients were older in groups 3 and 4 (79 and 76 respectively, P=0.65). The PSA was higher in the groups 3 and 4 (64 and 55 ng/mL) than the groups 1 and 2 (10.6 et 16 respectively, P=0.23). The number of positive biopsy was higher in the group 4 than the group 3 (5.6 vs. 4.6, P<0.0001), the chips were more invaded in the group 4 than the group 2 (41% vs. 11% P<0.0001), the Gleason score at TURP was higher in the group 4 than the group 2 (7.5 vs. 6.2 P<0.0001).

CONCLUSION

Our study underlines that the Pca of transition and peripheral zones seems to have distinct characteristics. When chips of TURP and BPx were both invaded, it was due to an aggressive cancer. The decision to explore the peripheral zone in the case of positive TURP must take clinical context into consideration.

Preneoplasia in the prostate gland with emphasis on high grade prostatic intraepithelial neoplasia

There are a variety of morphological patterns and processes that have been implicated in the pathogenesis of prostate cancer. Prostatic intraepithelial neoplasia (PIN), inflammation with or without atrophy, and adenosis (atypical adenomatous hyperplasia) have all been given candidate status as precursor lesions of prostatic adenocarcinoma. Based on decades of research, high grade prostatic intraepithelial neoplasia (HPIN), a proliferative lesion of prostatic secretory cells, has emerged as the most likely morphological pre-invasive lesion involved in the evolution of many but not all prostatic adenocarcinomas. In this manuscript, we briefly discuss other proposed precursors of prostatic adenocarcinoma and then focus on the history, diagnostic criteria and morphology of HPIN. The incidence of HPIN and its relationship to prostate cancer is reviewed. The differential diagnosis of large glandular patterns in the prostate is discussed in depth. Finally, we summarise the recent clinicopathological studies evaluating the clinical significance of HPIN and discuss follow-up strategies in men diagnosed with HPIN.

Concomitant high-grade prostatic intraepithelial neoplasia is associated with good prognosis factors and oncologic outcome after radical prostatectomy

OBJECTIVES

To assess correlations between concomitant high-grade prostatic intraepithelial neoplasia (HGPIN), pathological features and oncologic outcomes after radical prostatectomy (RP).

MATERIAL AND METHODS

We prospectively collected a single-institution database of 2,351 patients who underwent RP between 1998 and 2011.

RESULTS

1,272 (54.1%) patients had HGPIN on specimens. The mean follow-up was 28 months. Presence of HGPIN was significantly associated with a favorable preoperative risk status and with pathological factors of poor prognosis in RP specimens. Patients without HGPIN had a worse biochemical recurrence-free survival compared with those with HGPIN in RP specimen (log-rank test: p = 0.015). The 3-year RFS rate was 73.9% for the HGPIN group versus 67.2%. The absence of HGPIN was also significantly correlated with the use of androgen deprivation treatment during the follow-up (p < 0.001). In Cox multivariate analysis, taking into account the other prognostic pathological factors, HGPIN was not an independent predictive factor for PSA failure (p = 0.868).

CONCLUSION

HGPIN is associated with factors of good prognosis but fails to show independent significance when classical pathological prognostic factors are taken into account.

Comparison of transrectal prostate biopsy results with histology of transurethral resection of the prostate in men undergoing high-intensity focused ultrasound

INTRODUCTION

The aim of our study was to evaluate the significance of transurethral resection of the prostate (TURP) to detect prostate cancer (PCa). A comparison was performed of the TURP specimens of patients undergoing high-intensity focused ultrasound (HIFU) with the core biopsies.

MATERIALS AND METHODS

TURP before undergoing HIFU therapy was performed in 106 patients without neoadjuvant treatment. The resected tissue was subjected to histopathological evaluation and compared to the histological results of transrectal prostate biopsy.

RESULTS

Cancer was detected in the resected tissue of 69 patients (65%). A positive correlation of the amount of resected tissue and detection of PCa could be demonstrated in a multivariate analysis.

CONCLUSIONS

With a rate of 65% PCa detected by TURP, our data provide evidence that TURP might be suitable to detect PCa in a small group of selected patients with continuously rising PSA levels and several negative biopsies. On the other hand, these data underline/reinforce the necessity to treat the whole gland using modern treatment modalities such as HIFU and cryotherapy.

Precursors of prostate cancer

High-grade prostatic intraepithelial neoplasia (PIN) is the only accepted precursor of prostatic adenocarcinoma, according to numerous studies of animal models and man; other proposed precursors include atrophy and malignancy-associated changes (with no morphologic changes). PIN is characterized by progressive abnormalities of phenotype and genotype that are intermediate between benign prostatic epithelium and cancer, indicating impairment of cell differentiation and regulatory control with advancing stages of prostatic carcinogenesis. The only method of detection of PIN is biopsy because it does not significantly elevate serum prostate-specific antigen concentration and cannot be detected by ultrasonography. The mean incidence of PIN in biopsies is 9% (range, 4%-16%), representing about 115,000 new cases of isolated PIN diagnosed each year in the United States. The clinical importance of PIN is its high predictive value as a marker for adenocarcinoma, and its identification warrants repeat biopsy for concurrent or subsequent carcinoma, especially when multifocal or observed in association with atypical small acinar proliferation (ASAP). Carcinoma develops in most patients with PIN within 10 years. Androgen deprivation therapy and radiation therapy decrease the prevalence and extent of PIN, suggesting that these forms of treatment may play a role in prevention of subsequent cancer. Multiple clinical trials to date of men with PIN have had modest success in delaying or preventing subsequent cancer.

In situ and intraductal epithelial proliferations of prostate: definitions and treatment implications. Part 1: Prostatic intraepithelial neoplasia

What's known on the subject? and What does the study add? In the era of extended biopsy sampling of the prostate, multifocal high-grade prostatic intraepithelial neoplasia (HGPIN) is associated with a significantly higher rate of cancer diagnosis than unifocal HGPIN or a benign diagnosis. In addition, the cancers that are subsequently diagnosed in men with HGPIN on their initial biopsy tend to be smaller, lower grade and more commonly organ-confined. This has led to a reappraisal of the need and timing of repeat biopsies. The present paper provides a series of recommendations on the optimal timing of repeat biopsies in men with HGPIN on biopsy, based on the current available evidence. This is the first of a two part series reviewing the nature and clinical significance of in situ cellular proliferations in the prostate gland. This first part examines prostatic intraepithelial neoplasia (PIN), while the second part in the next supplement discusses intraductal carcinoma and ductal adenocarcinoma of the prostate. PIN is a precursor lesion in the development of some forms of adenocarcinoma of the prostate. In the 1990 s, high-grade PIN (HGPIN) on biopsy was a significant predictor of carcinoma, but this was due to incomplete sampling with sextant biopsies. With more extensive sampling in the last decade, the likelihood of identifying cancer after a diagnosis of HGPIN is not significantly different from a benign diagnosis. In several recent studies, it is now recognised that multifocal HGPIN is a better predictor of cancer than unifocal HGPIN. Most cases of cancer will be detected in the vicinity of the HGPIN, but up to 40% of cancers will occur in different sextants. In assessing potential markers for carcinoma in men with HGPIN on biopsy, α-methylacyl coenzyme-A racemase (AMACR) has emerged as a promising diagnostic tool. HGPIN with strong staining for AMACR is associated with a higher rate of cancer detection in subsequent biopsies compared with AMACR-negative HGPIN. Also, AMACR positivity in HGPIN is more commonly seen adjacent to carcinoma, and this may provide guidance as to the site of future biopsies.

Endoscope-assisted radical perineal prostatectomy

Dissection of the bladder neck is particularly important in patients who have previously had prostate surgery due to hyperplasia. We describe an endoscope-assisted radical perineal prostatectomy (RPP) technique that facilitates the dissection of the prostate-vesical junction. The technique was employed in four patients with a history of transurethral prostate resection. Before dissecting the prostate from the bladder neck during RPP, we circumscribed the bladder neck perurethrally with a Collins knife. The remaining of the RPP procedure was performed via the traditional approach. The incision of the prostate-vesical junction with the Collins knife protected the bladder-neck integrity and made the dissection of this junction easier. The final pathologic diagnosis was organ-confined prostate cancer with negative surgical margins. All the patients had continence during a 6-month follow-up. The major advantage of this technique is to precisely locate the prostate-vesical junction under direct vision. Our modified technique may prove to be a simple, less invasive, and oncologically safe method to manage the bladder neck perurethrally.

Precursor lesions to prostatic adenocarcinoma

High-grade prostatic intraepithelial neoplasia (PIN) is the one well-documented precursor to adenocarcinoma of the prostate. This review article defines both low- and high-grade PIN. Unusual variants of high-grade PIN are illustrated. Benign lesions that may be confused with high-grade PIN, including central zone histology, clear cell cribriform hyperplasia, and basal cell hyperplasia are described and illustrated. High-grade PIN is also differentiated from invasive acinar (usual) and ductal adenocarcinoma. The incidence of high-grade PIN, its relationship to carcinoma (including molecular findings), and risk of cancer on rebiopsy are covered in detail. Finally, intraductal carcinoma of the prostate, a controversial entity, is discussed and differentiated from high-grade PIN.

Precursor Lesions of Prostate Cancer

Several morphological lesions have been proposed that may act as potential precursor lesions of prostate cancer. These are the morphologically distinct entities of focal atrophy or post-atrophic hyperplasia (PAH), atypical adenomatous hyperplasia (AAH) or adenosis, and prostatic intraepithelial neoplasia (PIN). The diagnostic criteria of low-and high-grade PIN (LGPIN and HGPIN, respectively) and of lesions suspicious for cancer (LSC) have been established. In the present review, we present the current knowledge about the precursor lesions of prostate cancer. We focus on the epidemiology, pathogenesis, clinical markers, and differential diagnosis of PIN. The similarities between HGPIN and prostate cancer are also discussed. Furthermore, potential markers and management strategies (that is, repeat biopsy, chemoprevention, radical prostatectomy, radiotherapy) are outlined along with updated recommendations.

Testosterone therapy in hypogonadal men and potential prostate cancer risk: a systematic review

This paper provides a systematic review of the literature about prostate cancer risk associated with testosterone therapy for hypogonadism. A comprehensive search of MEDLINE, EMBASE and other resources was conducted to identify articles that highlight occurrences of prostate cancer in men receiving testosterone therapy for hypogonadism treatment. Articles that met study inclusion criteria were assessed for causality between testosterone treatment and prostate cancer, increased prostate-specific antigen or abnormal digital rectal examination findings. Of 197 articles relating to testosterone therapy, 44 met inclusion criteria: 11 placebo-controlled, randomized studies; 29 non-placebo-controlled studies of men with no prostate cancer history; and 4 studies of hypogonadal men with history of prostate cancer. Of studies that met inclusion criteria, none demonstrated that testosterone therapy for hypogonadism increased prostate cancer risk or increased Gleason grade of cancer detected in treated vs untreated men. Testosterone therapy did not have a consistent effect on prostate-specific antigen levels.

Contemporary clinical management of isolated high-grade prostatic intraepithelial neoplasia

High-grade prostatic intraepithelial neoplasia (HGPIN) is a premalignant lesion associated with increased risk of coexistent cancer or delayed progression to carcinoma. Extended biopsy schemes have improved the ability to rule out concurrent cancers, increased the detection of isolated HGPIN and removed the routine necessity for immediate repeat biopsy. As the natural history of HGPIN is poorly defined, and no non-invasive marker allows monitoring of progression to cancer, routine delayed interval biopsy should be considered in all patients. In this article, we present an overview of the existing literature on HGPIN and a proposed strategy for clinical management.

Prostatic intraepithelial neoplasia: recent advances

CONTEXT

There have been 2 putative prostatic cancer precursors, prostatic intraepithelial neoplasia (PIN) and atypical adenomatous hyperplasia (adenosis), but PIN remains as a well-known precancerous condition.

OBJECTIVE

To describe recent advances in knowledge of PIN and to better define the diagnostic criteria and differential diagnosis of PIN.

DATA SOURCES

Review of the pertinent literature and our experience.

CONCLUSIONS

The presence of ductal/acinar epithelial changes including nuclear enlargement, prominent nucleoli, chromatin alterations, and luminal complexity is an easy way to identify the disorder. Four main patterns of high-grade PIN (HGPIN) have been described: tufting, micropapillary, cribriform, and flat. In addition, variants of HGPIN have also been described. Both HGPIN and prostatic carcinoma share an increased incidence and severity with advancing age and with high rates of occurrence in the peripheral zone of the prostate. Furthermore, HGPIN and prostate cancer share genetic and molecular markers as well, with PIN representing an intermediate stage between benign epithelium and invasive carcinoma. The clinical significance of HGPIN is that it identifies patients at risk for prostatic carcinoma. With the increased use of extended biopsy protocols, clinicians are more likely to identify HGPIN and less likely to miss concurrent carcinoma.

Mechanisms of Disease: high-grade prostatic intraepithelial neoplasia and other proposed preneoplastic lesions in the prostate

High-grade prostatic intraepithelial neoplasia (HGPIN) is the most likely precursor of prostatic adenocarcinoma according to virtually all available evidence. This lesion is characterized by cellular proliferations within pre-existing ducts and acini, with nuclear and nucleolar enlargements similar to those seen in prostate cancer, although unlike cancer HGPIN retains a basal-cell layer. The recognition of HGPIN is clinically important because of the strong association between this disease and prostatic carcinoma. The predictive value for cancer of an initial diagnosis of HGPIN on needle biopsy has substantially declined, with values falling from 36% to 21%. A major factor contributing to this decline is related to increased use of needle biopsy core sampling, which has provided the means for many cancers associated with HGPIN to be detected on initial biopsy; repeat biopsy, even with good sampling, does not detect many additional cancers. Other possible findings in the prostate might indicate premalignant disease (low-grade prostatic intraepithelial neoplasia, atrophy, malignancy-associated changes, and atypical adenomatous hyperplasia or adenosis), but the data for these premalignant diseases are much less convincing than those for HGPIN.

Should high-grade prostatic intraepithelial neoplasia change our approach to infravesical obstruction?

OBJECTIVES

To investigate whether coexistence of high-grade prostatic intraepithelial neoplasia (HPIN) should change our therapeutic approach to infravesical obstruction.

MATERIAL AND METHODS

Of 505 patients who underwent sextant transrectal ultrasonography (TRUS)-guided prostate biopsy, 65 (12.8%) had HPIN and 29 of them underwent prostatectomy (23 transurethral resection of prostate (TURP), 6 open) due to obstructive urinary symptoms. Patients without carcinoma were followed up with semiannual prostate-specific antigen (PSA) and digital rectal examination. After a follow-up of 24.8 +/- 11.0 months, 19 of 29 patients who accepted our call had another sextant biopsy.

RESULTS

Mean age and initial mean PSA values of 29 patients were 67.6 +/- 6.7 years and 9.26 +/- 5.91 ng/ml, respectively. The final pathological evaluation of the surgical specimens revealed 2 prostatic adenocarcinomas both in the TURP group. The remaining 27 (93.2%) patients were found to have benign prostatic hyperplasia (BPH) and their serum PSA levels declined from 9.26 +/- 5.91 to 4.59 +/- 2.0 ng/ml 3 months after prostatectomy. Of the 19 patients who had another biopsy with a mean PSA value of 4.06 +/- 4.61 ng/ml, 15 and 4 of them had BPH and HPIN respectively.

CONCLUSIONS

Our preliminary data indicate that the presence of HPIN on TRUS-guided biopsies is not a factor to delay an indicated surgical intervention for infravesical obstruction.

Prostatic Intraepithelial Neoplasia: An Update

High-grade prostatic intraepithelial neoplasia (HGPIN) is commonly encountered on prostate needle biopsies and, based on epidemiologic, molecular, and animal models, has proven to be the most significant risk factor for prostate cancer and likely represents the premalignant phase of prostatic adenocarcinoma. This lesion is characterized by cellular proliferations within pre-existing ducts and glands, with nuclear and nucleolar enlargement similar to prostate cancer. However, unlike cancer, HGPIN retains a basal cell layer identifiable by immunohistochemistry with the basal cell-specific antibody cytokeratin 34bE12. The incidence of HGPIN identified in needle biopsies is as high as 25%, increases with age, and coexists with prostate cancer in approximately 85% of cases. There appears to be no causal relationship between HGPIN and serum prostate-specific antigen (total, percent free, or density) or radiographic characteristics on transrectal ultrasound. In a large series, the identification of HGPIN on initial needle biopsy is associated with about a 35% risk of prostate cancer on subsequent biopsies. Thus, the finding of HGPIN on prostate needle biopsy necessitates a second biopsy in a patient eligible for curative treatment. As a precursor lesion, HGPIN is currently a target for chemopreventive strategies, including antiandrogens and nutritional supplementation.

High-grade prostatic intraepithelial neoplasia

High-grade prostatic intraepithelial neoplasia (PIN) is now accepted as the most likely preinvasive stage of adenocarcinoma, almost two decades after its first formal description. PIN has a high predictive value as a marker for adenocarcinoma, and its identification warrants repeat biopsy for concurrent or subsequent invasive carcinoma. The only method of detection is biopsy; PIN does not significantly elevate serum prostate-specific antigen (PSA) concentration or its derivatives and cannot be detected by current imaging techniques, including ultrasound. Most patients with PIN will develop carcinoma within 10 years. PIN is associated with progressive abnormalities of phenotype and genotype, which are similar to cancer rather than normal prostatic epithelium, indicating impairment of cell differentiation with advancing stages of prostatic carcinogenesis. Androgen deprivation therapy decreases the prevalence and extent of PIN, suggesting that this form of treatment may play a role in chemoprevention.

WITHDRAWN:Epidemiology of prostate cancer and its precursors

Ahead of Print article withdrawn by publisher.

Detection of prostate cancer by TURP or open surgery in patients with previously negative transrectal prostate biopsies

OBJECTIVES

To evaluate retrospectively the effectiveness of transurethral resection of the prostate (TURP) in diagnosing prostate cancer in patients with obstructive voiding symptoms and a history of negative transrectal prostate biopsy but elevated prostate-specific antigen (PSA) and/or abnormal digital rectal examination (DRE).

METHODS

In 1189 consecutive patients undergoing TURP or open prostatectomy between 1994 and 2000 for obstructive voiding symptoms, we identified 445 patients (37.4%) with at least one previous set of transrectal prostate biopsies because of an elevated PSA level and/or abnormal DRE findings. The probability to detect prostate cancer by TURP (n = 423; 95%) or open surgery (n = 22; 5%) was investigated overall, as well as related to patient age, PSA level, DRE findings, number of previous biopsies, time from biopsy to surgery, and weight of resected tissue.

RESULTS

The mean number of preoperative negative biopsies per patient was 1.6 (range 1 to 8). The mean patient age was 69 years (range 48 to 89). The median PSA level and resection weight was 8.64 ng/mL and 32 g, respectively. Ninety-seven patients (21.8%) had abnormal DRE findings. Overall, prostate cancer was detected in 35 patients (7.9%). The cancer incidence was 5.5% (19 of 348) in patients with a normal DRE compared with 16.5% (16 of 97) in patients with an abnormal DRE (P <0.001; Fisher's exact test). The cancer rate was also related to age; other subgroups showed no statistically significant differences regarding cancer incidence.

CONCLUSIONS

In patients with previously negative biopsies, the diagnostic yield of TURP is low. Therefore, TURP for diagnostic purposes only cannot be recommended. However, in patients with an abnormal DRE and obstructive symptoms, surgery should be preferred over alternative treatment options.

Contemporary pathology of prostate cancer

In less than 20 years since the introduction of serum PSA and the spring-loaded 18-gauge prostatic biopsy needle, pathologists have adjusted to the limited tissue requirements of narrow needle specimens to apply criteria for diagnosis and grading of prostate cancer, borrowing from lessons learned from radical prostatectomies. Substantial gains have been made during this period in the understanding of precancerous lesions, mimics of malignancy, the criteria for minimal cancer, variants of cancer, and treatment-induced changes. The light microscopic findings remain the criterion standard for diagnosis against which all new techniques should be measured. Numerous findings have proven to be of value, including simple quantitation of histopathologic features, cancer volume, perineural invasion, and others.

Production of serum-free and total prostate-specific antigen due to prostatic intraepithelial neoplasia

OBJECTIVE

High serum total prostate-specific antigen (PSA) levels have proven to be predictive of concurrent cancer but the role of prostatic intraepithelial neoplasia (PIN) in the production of total (t) and free (f) PSA is still the subject of research. In this study we wanted to discover whether variations in serum fPSA and tPSA levels are caused by PIN.

MATERIAL AND METHODS

We reviewed the medical records of 87 patients: in 32 of them the diagnosis of isolated PIN was made from surgical samples (simple prostatectomy, n = 19; radical cystectomy, n = 13); in 30 patients a diagnosis of benign prostatic hyperplasia (BPH) without PIN or prostatic carcinoma was made after simple prostatectomy (n = 20) or radical cystectomy (n = 10); and in 25 patients a clinically significant prostatic cancer was diagnosed and these patients underwent radical prostatectomy. All patients underwent a standard preoperative evaluation, including serum fPSA and tPSA determinations and PSA density.

RESULTS

The frequency of isolated PIN in simple prostatectomy specimens was 6.3%. The mean f/t PSA ratios were 17.66% in the 32 patients with PIN, 19.2% in the 8 patients with low-grade PIN, 17.6% in the 24 patients with high-grade PIN, 24.2% in patients with BPH and 13% in patients who underwent radical prostatectomy.

CONCLUSIONS

We believe that to make a definitive diagnosis of isolated PIN without carcinoma, study of the whole prostate gland is necessary, in order to definitively exclude the presence of concurrent neoplastic foci. Our data show that PIN does not contribute to tPSA levels and density; however, it may be responsible for a slight reduction in the f/t PSA ratio, with a significant reduction in cases with high-grade PIN (17.6%) compared to those with BPH (24.2%).

Alpha-methylacyl-CoA racemase (P504S) expression in evolving carcinomas within benign prostatic hyperplasia and in cancers of the transition zone

Carcinomas of the transition zone (TZ) constitute approximately 20% of all prostate cancers. The TZ is the site of origin of grade 1 and grade 2 cancers, the most well-differentiated of the Gleason grade tumors, as well as for benign prostatic hyperplasia (BPH). In this regard, grade 1 carcinoma has architectural features that closely mimic gland-rich BPH nodules. Although a relationship between cancers arising in this zone and BPH has been suspected, such an association remains undefined. To gain insight into the origin, development, and progression of cancers arising in the TZ, we used a highly specific rabbit monoclonal antibody (P504S) directed against alpha-methylacyl-CoA racemase (AMACR) to study the expression of the enzyme in 25 cases of evolving and fully developed carcinomas of this zone. AMACR has been proposed as a new molecular marker for prostate cancer, because the enzyme is reportedly overexpressed in high-grade dysplasias, also termed prostatic intraepithelial neoplasia, a purported precursor of prostatic carcinoma, and in all grades of prostatic carcinoma of the peripheral zone. Using P504S, P63, or antikeratin 34beta E12 antibodies, we found it possible to define areas of transition from hyperplasia to carcinoma in 6 BPH nodules. In 3 other cancer-containing BPH nodules, staining for AMCAR was observed in benign hyperplastic glands that were juxtaposed to carcinoma. Enzyme expression was also evident in 5 additional cases in which BPH was found adjacent to cancer. In contrast; AMACR was not visualized in any other BPH nodules that we studied. Thus, using the enzyme as a marker, we document for the first time that some carcinomas of the TZ arise from an AMCAR-positive transition lesion within a subset of BPH nodules. Moreover, the finding of enhanced AMACR expression in benign glands within cancer-containing nodules as well as in BPH lesions adjacent to carcinoma suggests that in some cases, up-regulation of the enzyme may precede morphological evidence of neoplastic transformation. AMACR was lightly expressed in transition lesions and grade 1 carcinomas but more strongly expressed in higher-grade TZ cancers, suggesting that enzyme expression is enhanced with progression in this zone. Because AMACR is involved in the beta oxidation of branched fatty acids and their derivatives, enhanced expression of the enzyme in evolving carcinomas in BPH nodules, as well as its up-regulation in juxtaposed morphologically benign glands and grade 1 carcinomas, suggests that increased utilization of fatty acids may play an important role in carcinoma development and progression in the TZ.

Precancerous lesions and conditions of the prostate: from morphological and biological characterization to chemoprevention

Prostatic intraepithelial neoplasia (PIN) is composed of dysplastic cells with a luminal cell phenotype, expressing the androgen receptor as well as prostate-specific antigen. PIN is characterized by progressive abnormalities of phenotype that are intermediate between normal prostatic epithelium and cancer, indicating impairment of cell differentiation and regulatory control with advancing stages of carcinogenesis. High-grade PIN is considered the most likely precursor of prostatic carcinoma, according to virtually all available evidence. Androgen deprivation decreases the prevalence and extent of PIN and the degree of capillary vascularization (e.g., angiogenesis) in the surrounding stroma via suppression of vascular endothelial growth factor production. Prostatic carcinoma is also likely to arise from precursor lesions other than high-grade PIN such as low-grade PIN, atypical adenomatous hyperplasia, malignancy-associated foci, and atrophy.

Effect of androgen deprivation therapy on prostatic intraepithelial neoplasia

There is a marked decrease in the prevalence and extent of high-grade prostatic intraepithelial neoplasia (PIN) in men with prostate cancer after androgen deprivation therapy (ADT) when compared with untreated cases. Basal cell hyperplasia, cytoplasmic clearing, and prominent atrophy of benign acini, with decreased ratio of acini to stroma, accompany this decrease. These findings indicate that the benign and dysplastic prostatic epithelium is androgen dependent. In the normal prostatic epithelium, luminal secretory cells are more sensitive to the absence of androgen than basal cells, and the proliferative cells of high-grade PIN share this androgen sensitivity. The loss of some normal, hyperplastic, and dysplastic epithelial cells with ADT is probably because of acceleration of programmed single-cell death. Remarkably little is known about the comparative effect of different forms of chemical ADT on PIN and cancer, although there appears to be a limited and consistent repertoire of morphologic responses to all forms of this therapy. Conversely, blockade of 5alpha-reductase with finasteride has little or no effect on PIN (or benign epithelium and cancer), unlike other forms of ADT. A recent international consensus conference sponsored by the World Health Organization concluded that identification of high-grade PIN offered the possibility of chemoprevention with hormonal therapy to block the development of clinical cancer. Multiple chemoprevention trials are planned or under way to address this hypothesis.

Histological markers of risk and the role of high-grade prostatic intraepithelial neoplasia

The marked discrepancy between the prevalence of preclinical prostate cancer and the incidence of clinically manifest disease indicates a long latency phase and significant heterogeneity in the progression potential of early neoplastic lesions. There are a variety of histologic changes within prostatic epithelium that have been termed atypical or dysplastic. The 2 most widely studied of these lesions are prostatic intraepithelial neoplasia (PIN) and atypical adenomatous hyperplasia (AAH). Although associations between AAH and adenocarcinoma are spurious, those linking high-grade PIN (HGPIN) to cancer are far more established. There is a significantly increased risk for patients with isolated HGPIN to have prostate cancer confirmed on subsequent biopsy, suggesting that HGPIN is a marker for prostate carcinoma in addition to its potential role as a premalignant lesion. Autopsy studies reveal that HGPIN is found in association with cancer in 63% to 94% of malignant and 25% to 43% of benign prostates. Data on age and race reveal that African American men develop more extensive HGPIN at a younger age than white men. A wide spectrum of molecular/genetic abnormalities appears to be common to both HGPIN and prostate cancer. Data loss of 8p, 10q, 16q, 18q, and gain of 7q31, 8q, multiple copies of the c-myc genes, along with changes in chromatin texture, telomerase activity, cell cycle status, and proliferative indices collectively suggest that HGPIN is intermediate between benign epithelium and prostatic carcinoma with respect to these markers. These data indicate that HGPIN is important in neoplastic progression, and may present an appropriate target/marker for chemoprevention.

Chemoprevention for prostatic carcinoma: The role of flutamide in patients with prostatic intraepithelial neoplasia

High-grade prostatic intraepithelial neoplasia (HGPIN) is believed to be a precursor for prostatic adenocarcinoma. The prevalence of prostatic intraepithelial neoplasia (PIN) increases with advancing age. Autopsy studies suggest that PIN may precede the development of prostatic adenocarcinoma by up to 10 years. As such, HGPIN is believed to be a marker of increased risk. This provides a potential opportunity for chemoprevention. Flutamide is 1 agent with potential activity and limited side effects that may act to prevent or delay the onset of prostatic adenocarcinoma in men with HGPIN. A clinical trial is currently underway to assess the efficacy of flutamide.

Diagnosis of prostatic intraepithelial neoplasia: Prostate Working Group/consensus report

High-grade prostatic intraepithelial neoplasia (PIN) is the most likely precursor of prostatic carcinoma. PIN has a high predictive value as a marker for carcinoma, and its identification in biopsy specimens warrants repeat biopsy for concurrent or subsequent carcinoma. The only methods of detection are biopsy and transurethral resection; PIN does not significantly elevate serum PSA concentration or its derivatives, nor does it induce a palpable mass, and cannot be detected by ultrasound. Androgen deprivation therapy decreases the prevalence and extent of PIN, suggesting that this form of treatment may play a role in chemoprevention. Radiation therapy is also associated with a decreased incidence of PIN.

Epidemiology of high-grade prostatic intraepithelial neoplasia

This review summarizes published data dealing with the prevalence of high-grade prostatic intraepithelial neoplasia (HGPIN) in a variety of prostate tissue samples. Additionally, we have attempted to document the relationship between HGPIN and the pathological parameters of prostate cancer in autopsy and radical prostatectomy specimens. Studies reporting the prevalence of HGPIN in needle biopsies, transurethral resection specimens and radical prostatectomy specimens, and those documenting the lesion in postmortem settings are compared. We also summarize studies in which the distribution and/or extent of HGPIN was correlated with prostate cancer stage, grade and volume. There is significant variation in the reported frequency of HGPIN, particularly in needle biopsy specimens, with a range of 0.8-23.9%. The factors responsible for these discrepancies include the population studied, the limited sample size that needle biopsies represent, diagnostic inconsistencies and, possibly, tissue preparation/staining variables. Because of the important implications a diagnosis of HGPIN carries, there is a pressing need to achieve greater consistency in diagnosing and reporting the lesion. Better targeted educational efforts, including teaching courses, websites with illustrations and the possibility of teleconsultations, are among possible means to attain this goal. Better documentation of the evolution of HGPIN to cancer through clinical follow-up is also recommended.

Incidental prostatic adenocarcinomas and putative premalignant lesions in TURP specimens collected before and after the introduction of prostrate-specific antigen screening

BACKGROUND

Since the introduction of prostate-specific antigen (PSA) screening for the detection of prostatic adenocarcinoma (PCA), there has been an increase in the incidence of stage T1c PCA. The purpose of this study was to compare the frequency of incidental PCA found in transurethral resection of prostate (TURP) specimens for a 14-month period during 1989-1990 (before PSA screening was available) with the incidence of PCA for a 32-month period during 1997-1999 (after PSA screening became available).

DESIGN

Consecutive TURP specimens from the 2 time periods were reviewed to identify incidental PCA, prostatic intraepithelial neoplasia (PIN), and atypical adenomatous hyperplasia (AAH). Cases of TURP for palliative treatment of known advanced PCA were excluded from the study. All TURP specimens were fixed in 10% buffered formalin and were processed according to the same protocol.

RESULTS

We reviewed 533 and 449 TURP specimens for the time periods 1989-1990 and 1997-1999, respectively. Comparison of the results for these 2 time periods revealed that the combined prevalence of T1a and T1b PCA decreased over time from 12.9% to 8.0% (P =.06) with the introduction of PSA screening. A new group of T1c PCA was established in the post-PSA screening period of 1997-1999. There were no statistically significant differences in the incidences of T1a PCA, PIN, and AAH in TURP specimens for the 2 time periods.

CONCLUSION

The decreased incidence of T1b PCA in TURP specimens for the 1997-1999 period represents a shift in PCA staging. Some PCAs previously staged as T1b are now staged as T2 carcinomas, as a result of PSA screening and earlier clinical detection. The introduction of PSA screening has had no influence on the incidence of T1a PCA, PIN, or AAH in TURP specimens.

Morphological identification of the patterns of prostatic intraepithelial neoplasia and their importance

High grade prostatic intraepithelial neoplasia (PIN) is the most likely precursor of prostatic carcinoma. PIN has a high predictive value as a marker for carcinoma, and its identification in biopsy specimens warrants repeat biopsy for concurrent or subsequent carcinoma. The only methods of detection are biopsy and transurethral resection; PIN does not greatly raise the concentration of serum prostate specific antigen (PSA) or its derivatives, does not induce a palpable mass, and cannot be detected by ultrasound. Androgen deprivation decreases the prevalence and extent of PIN, suggesting that this form of treatment might play a role in chemoprevention. Radiotherapy is also associated with a decreased incidence of PIN.

[Incidence of high grade prostatic intraepithelial neoplasia in urologic practice]

High grade (PIN AG) intraepithelial neoplasia of the prostate is a likely precursor of prostate adenocarcinoma (PA) because of their association. Since the risk to suffer PA increases in patients with no previous PIN AG, its finding requires an arduous search for PA. This paper reviews the incidence of PIN AG in 499 histological studies in prostate transrectal biopsies, prostate TUR and adenomectomy specimens and radical prostatectomy (RP) sections. Evaluation of data obtained, type of presentation and association to prostate carcinoma, indicating the approach taken in the various cases.

Expression of pi-class glutathione S-transferase: two populations of high grade prostatic intraepithelial neoplasia with different relations to carcinoma

BACKGROUND/AIMS

Patients with high grade prostatic intraepithelial neoplasia of the transition zone appear to be at increased risk of developing prostatic carcinoma, although not to the same degree as patients with high grade prostatic intraepithelial neoplasia of the peripheral/central zone. Previous investigations have shown loss of expression of pi-class glutathione S-transferase (GST-pi; an enzyme that protects against electrophilic carcinogens) in prostatic carcinoma and in high grade prostatic intraepithelial neoplasia. The aim of this study was to compare the expression of GST-pi in high grade prostatic intraepithelial neoplasia of the transition zone with that in high grade prostatic intraepithelial neoplasia of the peripheral/central zone (that is, non-transition zone).

METHODS

Immunostaining with the anti-GST-pi antibody was performed on 20 high grade prostatic intraepithelial neoplasia samples of the transition zone, either isolated or associated with prostatic carcinoma (groups 1 and 2, respectively; 10 cases each) and on 20 high grade prostatic intraepithelial neoplasia samples of the non-transition zone, either isolated or associated with prostatic carcinoma (groups 3 and 4, respectively; 10 cases each). This study also included six samples of high grade prostatic intraepithelial neoplasia simultaneously present in the transition and non-transition zones and not associated with prostatic carcinoma (group 5). The presence of immunostaining, staining intensity, and the distribution of immunostaining were evaluated in the high grade prostatic intraepithelial neoplasia lesions and in the normal tissue and cancer areas.

RESULTS

The GST-pi antibody stained the cytoplasm of the cells lining the ducts and acini of normal prostate tissue. Staining was stronger and more diffuse in the basal cell layer than in the luminal (or secretory) cell layer. Immunohistochemical staining with anti-GST-pi antibodies failed to detect the enzyme in all prostatic carcinoma foci but one. Two patterns were detected in high grade prostatic intraepithelial neoplasia. One was represented by GST-pi staining similar to that of the normal tissue (pattern A). The other deviated from it and was characterised by absence of GST-pi expression in the secretory cells and abundant expression in scattered basal cells (pattern B). Pattern A staining was seen more frequently in the transition than in the non-transition zone. Pattern B staining was seen mainly in high grade prostatic intraepithelial neoplasia of non-transition zone associated with cancer.

CONCLUSIONS

The differential expression of GST-pi in the transition and non-transition zones indicates the existence of two populations with the morphological appearance of high grade prostatic intraepithelial neoplasia that might have different associations with carcinoma.

Prostatic intraepithelial neoplasia

High-grade prostatic intraepithelial neoplasia (PIN) is now accepted as the most likely pre-invasive stage of adenocarcinoma, a decade after its first formal description. PIN has a high predictive value as a marker for adenocarcinoma, and its identification warrants repeat biopsy for concurrent or subsequent invasive carcinoma. The only method of detection is biopsy; PIN does not significantly elevate serum prostate-specific antigen concentration or its derivatives and cannot be detected by ultrasound. Most studies suggest that most patients with PIN will develop carcinoma within 10 years. PIN is associated with progressive abnormalities of phenotype and genotype that are similar to cancer rather than normal prostatic epithelium, indicating impairment of cell differentiation with advancing stages of prostatic carcinogenesis. Androgen deprivation therapy decreases the prevalence and extent of PIN, suggesting that this form of treatment may play a role in chemoprevention.

Prostatic intraepithelial neoplasia and apoptosis in benign prostatic hyperplasia before and after the Chernobyl accident in Ukraine

The prevalence of prostatic intraepithelial neoplasia (PIN) in men who underwent surgery for benign prostatic hyperplasia (BPH) before and after the Chernobyl nuclear accident was studied. BPH samples were obtained by adenomectomy from 45 patients operated in 1984 before the accident (Group I), and 47 patients from the low contaminated Kiev City (Group II) and 76 from high contaminated area (Group III) operated between 1996 and 1998. Their BPH samples were examined histologically and immunohistochemically. The incidences of prostatic intraepithelial neoplasia (PIN) and high grade PIN (HGPIN) were 15.5 and 11.1% in Group I, 29.8 and 14.9% in Grpoup II, and 35. 5 and 19.7% in Group III. The difference between the incidences of PIN in Group I and III is significant (p<0.02). There was increased apoptosis in areas of PIN in Group II and III as compared to Group I (p<0.001). Since apoptosis has been shown to be associated with ionizing radiation and it is now found to be associated with PIN in patients diagnosed after the Chernobyl nuclear accident, this suggests that long-term low dose internal ionizing radiation potentially may cause prostate cancer.