The predictive value for prostate cancer of lesions that raise suspicion of concomitant carcinoma: an evaluation from a randomized, population-based study of screening for prostate cancer

Typing the atypical: Diagnostic issues and predictive markers in suspicious prostate lesions

As much as 5% of prostate biopsies yield findings equivocal for malignancy even for skilled uropathologist; such "grey zone" lesions have been addressed in many ways, although the acronym ASAP (atypical small acinar proliferation) is the most widely used when referring to an atypical focus suspicious, but not diagnostic, for malignancy. Since the introduction of this diagnostic category more than 20 years ago, debate has ensued over its histological characterization and clinical significance. Pathology reporting of ASAP, commonly based on strict morphological criteria and traditional immunohistochemical markers such as basal cell antibodies, has been improved by recent availability of novel immunohistochemical markers such as AMACR and ERG. Further pathological issues, such as the role of pre-analytical variables, number of tissue levels, interobserver variability, and association with prostatic intraepithelial neoplasia also play a role in the optimal assessment of ASAP. Apart from diagnostic issues, a major issue is ASAP predictive value for prostate cancer on repeat biopsy. Therefore, attempts have been made to identify clinical and biological parameters that could predict subsequent diagnosis of malignancy as well as define time and modality of repeat biopsy. Finally, pathological features of cancers detected after a previous ASAP diagnosis are compared with those diagnosed at first prostate biopsy.

Biopsy diagnosis of intraductal carcinoma is prognostic in intermediate and high risk prostate cancer patients treated by radiotherapy

AIM

We investigated the prognostic significance of intraductal carcinoma of the prostate (IDC-P) in biopsies and transurethral resections prior to external beam radiotherapy with or without androgen deprivation.

METHODS

Cohort 1 consisted of 118 intermediate risk prostate cancer patients treated by radiotherapy, with biochemical relapse as primary end-point (median follow-up 6.5 years). Cohort 2 consisted of 132 high risk patients, enrolled in a phase III randomised trial (EORTC 22863) comparing radiotherapy alone to radiotherapy with long-term androgen deprivation (LTAD) with clinical progression free survival as primary end-point (median follow-up 9.1 years). Presence of IDC-P was identified after central review. Multivariable regression modelling and Kaplan-Meier analysis were performed with IDC-P as dichotomous variable.

RESULTS

IDC-P was a strong prognosticator for early (<36 months) biochemical relapse (HR 7.3; p = 0.007) in cohort 1 and for clinical disease-free survival in both arms of cohort 2 (radiotherapy arm: HR 3.5; p < 0.0001; radiotherapy plus LTAD arm: HR 2.8, p = 0.018). IDC-P retained significance after stratification for reviewed Gleason score in the radiotherapy arm (HR 2.3; p = 0.03). IDC-P was a strong prognosticator for metastatic failure rate (radiotherapy arm: HR 5.3; p < 0.0001; radiotherapy plus LTAD arm: HR 3.6; p = 0.05).

CONCLUSIONS

IDC-P in diagnostic samples of patients with intermediate or high risk prostate cancer is an independent prognosticator of early biochemical relapse and metastatic failure rate after radiotherapy. We suggest that the presence of IDC-P in prostate biopsies should routinely be reported.

Development and validation of a nomogram for predicting a positive repeat prostate biopsy in patients with a previous negative biopsy session in the era of extended prostate sampling

OBJECTIVE

To create a nomogram for predicting the probability of a positive biopsy in men with one or more previous negative biopsies, as the false-negative rate of prostate biopsy in contemporary series remains substantial, and there is a need to identify those with a negative result but with a high risk of having unrecognized prostate cancer.

PATIENTS AND METHODS

The study included 408 patients from Cleveland Clinic who had one or more repeat biopsies after an initial negative biopsy from 1999 to 2008. Another 470 men with the same criteria were used to validate the nomogram. Nomogram variables included age, family history of prostate cancer, body mass index, findings on a digital rectal examination, prostate-specific antigen (PSA) level, PSA slope, total prostate volume, months from initial negative biopsy session, months from previous negative biopsy, cumulative number of negative cores previously taken and history of high-grade intraepithelial neoplasia or atypical small acinar proliferation. We calculated the nomogram predicted probability in each patient. These predicted outcomes were compared with the actual biopsy results. The area under the receiver operating characteristic (ROC) curve was calculated as a measure of discrimination.

RESULTS

The mean number of previous negative biopsies was 1.5, and the mean number of cores per session was 19.1. Of the original development data, 129 men (31.6%) had prostate cancer. A nomogram was constructed that had a concordance index of 0.72, which was greater than any single risk factor. In the validation group the area under the ROC curve was 0.62.

CONCLUSIONS

Our nomogram for predicting a positive repeat biopsy can provide important additional information to aid the urologist and patient with a negative biopsy in evaluating clinical options.

Risk factors for prostate cancer detection after a negative biopsy: a novel multivariable longitudinal approach

PURPOSE

To introduce a novel approach for the time-dependent quantification of risk factors for prostate cancer (PCa) detection after an initial negative biopsy.

PATIENTS AND METHODS

Data for 1,871 men with initial negative biopsies and at least one follow-up biopsy were available. Piecewise exponential regression models were developed to quantify hazard ratios (HRs) and define cumulative incidence curves for PCa detection for subgroups with specific patterns of risk factors over time. Factors evaluated included age, race, serum prostate-specific antigen (PSA) concentration, PSA slope, digital rectal examination, dysplastic glands or prostatitis on biopsy, ultrasound gland volume, urinary symptoms, and number of negative biopsies.

RESULTS

Four hundred sixty-five men had PCa detected, after a mean follow-up time of 2.8 years. All of the factors were independent predictors of PCa detection except for PSA slope, as a result of its correlation with time-dependent PSA level, and race. PSA (HR = 3.90 for > 10 v 2.5 to 3.9 ng/mL), high-grade prostatic intraepithelial neoplasia/atypical glands (HR = 2.97), gland volume (HR = 0.39 for > 50 v < 25 mL), and number of repeat biopsies (HR = 0.36 for two v zero repeat biopsies) were the strongest predictors. Men with high-risk versus low-risk event histories had a 20-fold difference in PCa detection over 5 years.

CONCLUSION

Piecewise exponential models provide an approach to longitudinal analysis of PCa risk that allows clinicians to see the interplay of risk factors as they unfold over time for individual patients. With these models, it is possible to identify distinct subpopulations with dramatically different needs for monitoring and repeat biopsy.

False-negative prostate needle biopsies: frequency, histopathologic features, and follow-up

Little is known about the frequency, histopathologic characteristics, and clinical consequences of false-negative prostate biopsies, that is, biopsies classified as benign but containing adenocarcinoma or atypical suspicious glands [atypical small acinar proliferations (ASAP)]. Objective of this study was to evaluate false-negative prostate biopsy in a prostate cancer screening setting. Prostate biopsy sets of 196 participants of a screening trial, which had been reported as "benign" at initial diagnosis, followed by a diagnosis of adenocarcinoma in a subsequent screening round were reviewed by 2 urologic pathologists. Adenocarcinoma was identified in 19 biopsy cores corresponding to 16 (8.2%) patients and ASAP in 24 cores, corresponding to 19 patients (9.7%). All missed prostate cancers were Gleason score 6 (3+3). After correction for patient selection, the overall false-negative biopsy rate was estimated to be 2.4%; 1.1% for prostate cancer; and 1.3% for ASAP. Clinicopathologic features at the time of initial biopsy and of subsequent prostate cancer diagnosis did not differ between patients with a false-negative or true benign biopsy. Relatively low number of atypical glands (<10 glands), intense intermingling with preexistent glands or lack of architectural disorganization were the most prominent risk factors for a false-negative diagnosis. Another potential pitfall was the presence of prostate cancer variants, as 1 adenocarcinoma was of foamy gland type and 3 of pseudohyperplastic type. Routine examination of at least 1 level of prostate biopsy sets at high magnification and awareness of histologic prostate cancer variants might reduce the risk of missing or misinterpreting a relevant lesion at prostate biopsy evaluation.

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.

[Clinical significance of prostatic intraepithelial neoplasm and atypical small acinar proliferation: relationship with prostate cancer]

INTRODUCTION

Prostatic intraepithelial neoplasia (PIN) and atypical small acinar proliferation (ASAP) in the setting of prostatic needle biopsies are considered premalignant although questions still remain.

OBJECTIVES

In this paper, we have studied the clinical relevance of these histologic findings.

MATERIAL AND METHODS

We collected 138 subjects (108 PIN, 30 ASAP); in 67% we performed a second biopsy and the rate of cancer in this late biopsy were 19% and 27% respectively. We cannot identify any clinical factor to predict the finding of cancer in the re-biopsy (PSA, age, digital rectal examination, prostatic volume).

RESULTS

In the follow-up, we observed higher rates of cancer for the ASAP; the finding of ASAP was the single clinical or histopathological factor that was an independent predictor of cancer.

CONCLUSIONS

We observed that the finding of ASAP was an indication for re-biopsy because of the higher rates of cancer; on the contrary, the paper of PIN in the prostatic needle biopsy still requires further investigation.

My approach to intraductal lesions of the prostate gland

The morphologically heterogeneous (intra)ductal lesions of the prostate frequently present a diagnostic challenge, particularly when found within prostate needle biopsies. By current convention, all high-grade intra-acinar and intraductal neoplastic lesions of prostatic origin fall under the diagnostic umbrella term: prostatic intraepithelial neoplasm (PIN). Although a long-standing contentious issue, some lesions currently adhering to the diagnostic criteria of PIN may actually represent the intraductal spread of (generally high grade) invasive cancer. Illustrating this fact, the well-described ductal subtype of prostatic adenocarcinoma is frequently associated with conventional-type acinar adenocarcinoma, and has a tendency to propagate within adjacent intact prostatic ducts. Clearly, the misdiagnosis of lesions representing invasive disease as preinvasive has the potential for unfavourable clinical sequelae. As yet, however, many of these lesions have escaped the establishment of reliable morphologic criteria or immunohistochemical differentiation for diagnosis. By defining stringent architectural and cytonuclear features specific for each of these lesions, it may be feasible to separate potentially sinister lesions from the subset of traditional (preinvasive) PIN lesions with limited clinical urgency. This review discusses the (intra)ductal lesions of the prostate, along with their differential diagnoses. Given the current state of knowledge, a pragmatic approach to their effective reporting is outlined, taking into consideration the clinical implications, as well as current guidelines for treatment and follow-up.

High-grade prostatic intraepithelial neoplasia in needle biopsy as risk factor for detection of adenocarcinoma: current level of risk in screening population

OBJECTIVES

To assess the current incidence of prostate carcinoma detection in serial biopsies in a prostate-specific antigen-based screening population after a diagnosis of isolated high-grade prostatic intraepithelial neoplasia (HG-PIN) in needle biopsy tissue.

METHODS

We retrospectively identified 190 men with a diagnosis of isolated HG-PIN in needle biopsy tissue. Most men (86%) were diagnosed from 1996 to 2000. Logistic regression analysis was used to predict the presence of carcinoma in these 190 men and in a control group of 1677 men with only benign prostatic tissue in needle biopsy tissue.

RESULTS

The cumulative risk of detection of carcinoma on serial sextant follow-up biopsies was 30.5% for those with isolated HG-PIN compared with 26.2% for the control group (P = 0.2). Patient age (P = 0.03) and serum prostate-specific antigen level (P = 0.02) were significantly linked to the risk of cancer detection, but suspicious digital rectal examination findings (P = 0.1), the presence of HG-PIN (P = 0.2), and the histologic attributes of PIN were not (all with nonsignificant P values). HG-PIN found on the first repeat biopsy was associated with a 41% risk of subsequent detection of carcinoma compared with an 18% risk if benign prostatic tissue was found on the first repeat biopsy (P = 0.01).

CONCLUSIONS

The results of our study have shown that the current level of risk for the detection of prostate carcinoma in a screened population is 30.5% after a diagnosis of isolated HG-PIN in a needle biopsy. This risk level is lower than the previously reported risk of 33% to 50%. HG-PIN is a risk factor for carcinoma detection only when found on consecutive sextant biopsies. The data presented here should prompt reconsideration of repeat biopsy strategies for HG-PIN, and re-evaluation of the absolute necessity of repeat biopsy for all patients with HG-PIN.

Recursive partitioning for risk stratification in men undergoing repeat prostate biopsies

BACKGROUND

The current study was performed to identify risk factors and risk groups for carcinoma detection in men undergoing repeat prostate biopsies.

METHODS

The medical records of all men who had a negative initial prostate biopsy and underwent at least one repeat biopsy between 1992 and 2003 were reviewed to extract age, race, family history of prostate carcinoma, body mass index, referral indication, all prostate-specific antigen (PSA) values, digital rectal examination, PSA density (PSAD), the presence of a hypoechoic lesion, and the presence of high-grade prostatic intraepithelial neoplasia (HGPIN) on initial biopsy. Risk factors for a subsequent diagnosis of prostate carcinoma were identified using the log-rank test and a stepwise, stratified Cox regression model. Based on the risk factors identified by Cox regression analysis, recursive partitioning was further used for risk stratification.

RESULTS

A total of 373 patients underwent 975 biopsy procedures. During a median follow-up of 37.0 months, prostate carcinoma was detected in 107 of 373 patients (28.9%). Independent predictors of a positive biopsy (P < 0.05) were PSA doubling time (PSADT), PSAD, referral indication, the presence of HGPIN, patient age, and family history of prostate carcinoma. Recursive partitioning identified 4 distinct risk groups that were characterized by their PSADT and PSAD and the presence of HGPIN and had estimated 2-year and 5-year carcinoma detection rates of 3 +/- 1% and 21 +/- 4%, 28 +/- 5% and 40 +/- 7%, 22 +/- 6% and 58 +/- 8%, and 66 +/- 9% and 100%, respectively.

CONCLUSIONS

The authors identified a series of independent risk factors for prostate carcinoma detection after an initial negative prostate biopsy and characterized clinically meaningful and distinct patient risk groups. Despite a negative initial biopsy, patients with high-risk features remain at risk for the detection of prostate carcinoma.

uPM3, a new molecular urine test for the detection of prostate cancer

OBJECTIVES

To evaluate, in a multicenter study, the diagnostic performance of a new molecular test uPM3 for detecting prostate cancer cells in urine because of the need for better methods to identify patients at risk of prostate cancer.

METHODS

The uPM3 test is a nucleic acid amplification assay detecting simultaneously in the urine the relative expression of prostate-specific antigen (PSA) mRNA as a marker of prostate cells and PCA3RNA, which is selectively expressed in most types of prostate cancer. The test is performed using the isothermic nucleic acid-based amplification method, and the two targets are simultaneously detected in real-time fluorescence using specific beacons as probes in a thermostated spectrofluorometer. The test was performed on the first voided urine obtained after careful digital rectal examination of the prostate in men undergoing transrectal ultrasound-guided prostate biopsy.

RESULTS

Of 517 patients undergoing biopsy at five centers, 443 (86%) had an assessable sample. Of those, 21%, 55%, and 24% had a total PSA level of less than 4 ng/mL, between 4 and 10 ng/mL, and greater than 10 ng/mL. The corresponding percentage of biopsies positive for cancer in these three groups was 20%, 35%, and 44%. The overall uPM3 sensitivity and specificity was 66% and 89%, respectively. In men with a PSA level less than 4 ng/mL, the sensitivity was 74% and specificity 91%. In those with a PSA level of 4 to 10 ng/mL, the sensitivity was 58% and specificity 91%. In those with a PSA level greater than 10 ng/mL, the sensitivity and specificity was 79% and 80%, respectively. The positive predictive value of uPM3 was 75% compared with 38% for total PSA, and the negative predictive value was 84% compared with 89% and 80% for a PSA cutoff of 2.5 and 4.0 ng/mL, respectively. The overall accuracy was 81% compared with 43% and 47% for total PSA at a cutoff of 2.5 and 4.0 ng/mL, respectively.

CONCLUSIONS

These results suggest that the uPM3 molecular urine test may be an important adjunct to current methods for the detection of early prostate cancer.

Prostate cancer detection and tumor characteristics in men with multiple biopsy sessions

PURPOSES

To address prostate cancer (PCa) detection with respect to the number of biopsy sessions performed, to identify risk factors for detection after a negative biopsy, and to analyze the clinical characteristics of the detected tumors.

SCOPE

Only biopsied men (sextant) were included. A total of 1011 biopsy sessions were carried out in 770 men; 172 underwent a second prostate biopsy and 51 a third biopsy. During the first biopsy round, 111 cancers were found (14.4%), 27 in the second (15.7%), and five during the third round (9.8%), P=0.156. Only high-grade PIN or atypia were identified as independent predictors or PCa detection in subsequent biopsies (P=0.008). A nonsignificant increase of clinically localized tumors, and a decrease of metastatic and poorly differentiated cases were found when more biopsy sessions were needed for detection.

CONCLUSIONS

A nonsignificant trend to lower cancer detection rates and less clinical relevance of the tumors detected can be observed when more biopsy rounds are needed for detection.

High-grade Prostatic Intraepithelial Neoplasia on Needle Biopsy

The importance of isolated high-grade prostatic intraepithelial neoplasia (HGPIN) on needle biopsy is its association with synchronous invasive carcinoma. The relevance of this relationship has been called into question in recent years. In our study, we examined whether the histologic subtype of HGPIN (ie, tufting, micropapillary, cribriform, flat) and/or the number of core biopsies involved by HGPIN was predictive of a subset of men who were at higher risk of having invasive carcinoma on follow-up biopsies. We examined 200 sets of needle biopsies with a diagnosis of isolated HGPIN. Patient age ranged from 46 to 90 years (mean 66.4 years). The breakdown of the histologic subtypes of HGPIN is as follows: tufting 59%, micropapillary 34.3%, cribriform 6.2%, and flat 0.5%. A total of 132 patients (66%) had follow-up biopsies. Prostatic adenocarcinoma was identified in 28.8% of patients with 89.5% of cancers identified on the first two follow-up biopsies. For men that had two or more cores with HGPIN on the initial biopsy, 35.9% eventually had cancer on follow-up whereas men with only single core involvement had cancer in 22% of cases. Men with tufting/flat HGPIN on the initial biopsy had cancer on follow-up in 31.9% of cases, whereas the micropapillary/cribriform subtype was associated with cancer in 22% of follow-up biopsies. The histologic findings on the first repeat biopsy can be quite informative as to the risk of synchronous invasive carcinoma. Of the men with HGPIN on the first repeat biopsy, 32% eventually had cancer on follow-up. Additionally, if multiple cores were involved by HGPIN on the first repeat biopsy, the risk of finding cancer was 50%, regardless of single or multiple core involvement on the initial biopsy. Men with a benign diagnosis on the first repeat biopsy had a 14% risk of having cancer on follow-up. These data indicate that the multiple core involvement by HGPIN, both on initial and first repeat biopsy, defines a subset of men that are at increased risk of harboring synchronous invasive carcinoma. The histologic subtype of PIN does not appear to be as informative.

A nomogram for predicting a positive repeat prostate biopsy in patients with a previous negative biopsy session

PURPOSE

Although prostate cancer is found in about 30% of patients at the initial biopsy session, there is a need to identify those with a negative result but who are at high risk. Although individual risk factors have been found to be associated with cancer, patient counseling requires the integration of multiple risk factors to obtain a prediction for the individual.

MATERIALS AND METHODS

We studied 343 patients with at least 1 initial negative biopsy who were tested from August 1999 to September 2001. At each biopsy session we recorded patient age, family history of prostate cancer, serum prostate specific antigen (PSA), PSA slope, digital rectal examination findings, months from the initial biopsy session, cumulative number of negative cores previously obtained, and history of high grade prostatic intraepithelial neoplasia or atypical small acinar proliferation. Through Cox regression analysis we determined the association of each variable with time to a positive biopsy. A nomogram was constructed using all variables and discrimination was calculated as the concordance index.

RESULTS

There were 661 biopsy sessions. A mean of 2.9 biopsy sessions were performed per patient and a mean of 9.15 cores were obtained per biopsy session for a mean of 25.2 per patient. Overall 20% of patients had cancer at the second biopsy session. The cumulative number of negative cores obtained, PSA slope, history of high grade prostatic intraepithelial neoplasia and history of atypical small acinar proliferation were associated with repeat biopsy findings (all p <0.05). A nomogram was constructed that had a concordance index of 0.70, which was greater than that of any single risk factor.

CONCLUSIONS

We created a nomogram that predicts a positive biopsy after a previous negative biopsy session. It provides a wide range of probabilities for cancer and may improve clinical judgment before the decision to repeat biopsy.