Should a Gleason score be assigned to a minute focus of carcinoma on prostate biopsy?

Risk score model to automatically detect prostate cancer patients by integrating diagnostic parameters

Introduction

Prostate cancer (PCa) is one of the prevailing forms of cancer among men. At present, multiparametric MRI is the imaging method for localizing tumors and staging cancer. Radiomics plays a key role and hold potential for PCa detection, reducing the need for unnecessary biopsies, characterizing tumor aggression, and overseeing PCa recurrence post-treatment.

Methods

Furthermore, the integration of radiomics data with clinical and histopathological data can further enhance the understanding and management of PCa and decrease unnecessary transfers to specialized care for expensive and intrusive biopsies. Therefore, the aim of this study is to develop a risk model score to automatically detect PCa patients by integrating non-invasive diagnostic parameters (radiomics and Prostate-Specific Antigen levels) along with patient's age.

Results

The proposed approach was evaluated using a dataset of 189 PCa patients who underwent bi-parametric MRI from two centers. Elastic-Net Regularized Generalized Linear Model achieved 91% AUC to automatically detect PCa patients. The model risk score was also used to assess doubt cases of PCa at biopsy and then compared to bi-parametric PI-RADS v2.

Discussion

This study explored the relative utility of a well-developed risk model by combining radiomics, Prostate-Specific Antigen levels and age for objective and accurate PCa risk stratification and supporting the process of making clinical decisions during follow up.

A Novel Combination of Serum Markers in a Multivariate Model to Help Triage Patients Into “Low-” and “High-Risk” Categories for Prostate Cancer

Background

Almost 50,000 men in the United Kingdom (UK) are diagnosed each year with prostate cancer (PCa). Secondary referrals for investigations rely on serum prostate-specific antigen (PSA) levels and digital rectal examination. However, both tests lack sensitivity and specificity, resulting in unnecessary referrals to secondary care for costly and invasive biopsies.

Materials and Methods

Serum samples and clinical information were collected from N = 125 age-matched patients (n = 61 non-PCa and n = 64 PCa) and analyzed using Biochip Array Technology on high-sensitivity cytokine array I (IL-2, IL-4, IL-6, IL-8, IL-10, IL-1α, IL-1β, TNFα, MCP-1, INFγ, EGF, and VEGF), cerebral array II (CRP, D-dimer, neuron-specific enolase, and sTNFR1), and tumor PSA oncology array (fPSA, tPSA, and CEA).

Results

The data showed that 11/19 (68.8%) markers were significantly different between the non-PCa and the PCa patients. A combination of EGF, log₁₀ IL-8, log₁₀ MCP-1, and log₁₀ tPSA significantly improved the predictive potential of tPSA alone to identify patients with PCa (DeLong, p < 0.001). This marker combination had an increased area under the receiver operator characteristic (0.860 vs. 0.700), sensitivity (78.7 vs. 68.9%), specificity (76.5 vs. 67.2%), PPV (76.2 vs. 66.7%), and NPV (79.0 vs. 69.4%) compared with tPSA.

Conclusions

The novel combination of serum markers identified in this study could be employed to help triage patients into “low-” and “high-risk” categories, allowing general practitioners to improve the management of patients in primary care settings and potentially reducing the number of referrals for unnecessary, invasive, and costly treatments.

Limited Adenocarcinoma of the Prostate on Needle Core Biopsy

CONTEXT.—

Grading small foci of prostate cancer on a needle biopsy is often difficult, yet the clinical significance of accurate grading remains uncertain.

OBJECTIVE.—

To assess if grading of limited adenocarcinoma on prostate biopsy specimen is critical.

DESIGN.—

We studied 295 consecutive patients undergoing extended-sextant biopsy with only 1-core involvement of adenocarcinoma, followed by radical prostatectomy.

RESULTS.—

The linear tumor lengths on these biopsy specimens were: less than 1 mm (n = 114); 1 mm or more or less than 2 mm (n = 82); 2 mm or more or less than 3 mm (n = 35); and 3 mm or more (n = 64). Longer length was strongly associated with higher Grade Group (GG) on biopsy or prostatectomy specimen, higher risk of extraprostatic extension/seminal vesicle invasion and positive surgical margin, and larger estimated tumor volume. When cases were compared based on biopsy specimen GG, higher grade was strongly associated with higher prostatectomy specimen GG, higher incidence of pT3/pT3b disease, and larger tumor volume. Outcome analysis further showed significantly higher risks for biochemical recurrence after radical prostatectomy in patients with 1 mm or more, 2 mm or more, 3 mm or more, GG2-4, GG3-4, GG4, less than 1 mm/GG2-4, less than 1 mm/GG3-4, less than 2 mm/GG3-4, 3 mm or more/GG2-4, or 3 mm or more/GG3-4 tumor on biopsy specimens, compared with respective control subgroups. In particular, 3 mm or more, GG3, and GG4 on biopsy specimens showed significance as independent prognosticators by multivariate analysis. Meanwhile, there were no significant differences in the rate of upgrading or downgrading after radical prostatectomy among those subgrouped by biopsy specimen tumor length (eg, <1 mm [44.7%] versus ≥1/<2 mm [41.5%] versus ≥2/<3 mm [45.7%] versus ≥3 mm [46.9%]).

CONCLUSIONS.—

These results indicate that pathologists still need to make maximum efforts to grade relatively small prostate cancer on biopsy specimens.

A grading dilemma; Gleason scoring system: Are we sufficiently compatible? A multi center study

Objective

Gleason scoring is the grading system which strongly predicts the prognosis of prostate cancer. However, even being one of the most commonly used systems, the presence of different interobserver agreement rates push the uropathologists update the definitons of the Gleason patterns. In this study, we aimed to determine the interobserver agreement variability among 7 general pathologists, and one expert uropathologist from 6 different centers.

Methods

A set of 50 Hematoxylin & Eosin stained slides from 41 patients diagnosed as prostate cancer were revised by 8 different pathologists. The pathologists were also grouped according to having their residency at the same institute or working at the same center. All pathologists' and the subgroups' Gleason scores were then compared for interobserver variability by Fleiss' and Cohen's kappa tests using R v3.2.4.

Results

There were about 8 pathologists from 6 different centers revised all the slides. One of them was an expert uropathologist with experience of 18 years. Among 7 general pathologists 4 had surgical pathology experience for over 5 years whilst 3 had under 5 years. The Fleiss' kappa was found as 0.54 for primary Gleason pattern, and 0.44 for total Gleason score (moderate agreement). The Fleiss' kappa was 0.45 for grade grouping system.

Conclusion

Assigning a Gleason score for a patient can be problematic because of different interobserver agreement rates among pathologists even though the patterns were accepted as well-defined.

The 2019 International Society of Urological Pathology (ISUP) Consensus Conference on Grading of Prostatic Carcinoma

Five years after the last prostatic carcinoma grading consensus conference of the International Society of Urological Pathology (ISUP), accrual of new data and modification of clinical practice require an update of current pathologic grading guidelines. This manuscript summarizes the proceedings of the ISUP consensus meeting for grading of prostatic carcinoma held in September 2019, in Nice, France. Topics brought to consensus included the following: (1) approaches to reporting of Gleason patterns 4 and 5 quantities, and minor/tertiary patterns, (2) an agreement to report the presence of invasive cribriform carcinoma, (3) an agreement to incorporate intraductal carcinoma into grading, and (4) individual versus aggregate grading of systematic and multiparametric magnetic resonance imaging-targeted biopsies. Finally, developments in the field of artificial intelligence in the grading of prostatic carcinoma and future research perspectives were discussed.

Gleason drift in the NIHR ProtecT study

AIMS

There is increasing evidence of Gleason score (GS) drift in prostatic core biopsies during the last two decades. The ProtecT study is a randomized controlled study and provides an excellent cohort to study the effect of time, prostate-specific antigen (PSA) level, perineural invasion, tumour length and age on GS.

METHODS AND RESULTS

The ProtecT study recruited men in the United Kingdom between 1999 and 2010. The Gleason scores were grouped into four categories ≤ 3 + 3, 3 + 4, 4 + 3 and ≥ 4 + 4 for analysis. Data from England between 2000 and 2012 were also available. A total of 3282 biopsies containing cancer were analysed. For each year of the ProtecT study, the odds of being diagnosed with a higher GS category increased by 4.9%. Higher GS was also associated with perineural invasion, increasing tumour length, age and PSA level. While biopsy GS from England was incomplete, it also showed a marked decrease in GS five and six tumours during the same period.

CONCLUSION

There was GS drift from 3 + 3 to 3 + 4 with time in the ProtecT study, but there appeared to be no significant change in percentage of GS 4 + 3 or higher. This drift was less dramatic when compared to GS in the rest of England.

[Documentation quality of histopathology reports of prostate needle biopsies: a snapshot]

BACKGROUND

A standardized assessment of findings from prostate needle biopsies in pathology is of great importance for the individual recommendations for therapy of patients with prostate cancer. To this end criteria were developed which are formulated as recommendations in the S3 guidelines for prostate cancer and in joint instructions of the Bundesverband Deutscher Pathologen (BDP, "National Association of German Pathologists") and the Deutsche Gesellschaft für Pathologie (DGP, "German Society of Pathology"). In this article the findings from tumor positive prostate needle biopsies taken from various institutes in Germany, were investigated exclusively to determine to what extent the recommended parameters were followed.

MATERIAL AND METHODS

The study encompassed the findings from 91 patients with a mean age of 65.3 years from whom an average of 9.3 biopsy samples from different regions of the prostate were submitted. All diagnosed tumors corresponded to a standard type adenocarcinoma according to the classification of the World Health Organization (WHO) which was detected in an average of 2.5 biopsy regions per patient. The assessment was made from H & E stained serial sections which was supplemented in 11 (12.1%) cases by special staining methods and in 40 (44%) cases by immunohistochemical staining techniques. The length of the needle biopsy was documented in 88 (96.7%) cases and the tumor spread also in 88 cases. The tumor stage was reported in 16 cases (17.6%).

RESULTS

The Gleason grading score (GS) was reported in all 91 cases whereby the old GS was explicitly used in 1 case and the modified GS in all other cases. The allocated GS ranged from 4 to 10 whereby 8 cases were graded as ≤5, 46 as GS grade 6, 27 as GS grade 7 and 10 as GS >7. Out of 45 cases with several positive biopsy samples, 38 were uniformly graded (84.4%), 6 out of the 7 samples which were not uniformly graded were allocated a GS of 6 or 7 and 1 sample was graded as GS 6-9. In 64 cases (70.3%) the conventional 3-stage WHO grading (n=42) and the Helpap grading (n=22) were additionally used. The WHO and Helpap grading scores were found to be highly correlated with the GS grading scores and the Union for International Cancer Control (UICC) grading scores derived from it (χ²-test, p<0.001), although surprising allocations were selected in isolated cases.

CONCLUSION

In total, the only serious deficits were that in three cases (3.3%) no information was supplied on the estimated spread of the tumor in the tumor positive biopsies because this information can be decisive for therapy decisions, particularly for the selection of an active surveillance strategy. Also a relatively large number of cases were assigned a GS score ≤ 5 which is not recommended in the modified Gleason grading. Furthermore, translation of the GS into the other grading forms used revealed that the biological assessment of the GS showed clear differences between the various participating institutes. In conclusion, the findings of the pathologists as a rule incorporated all the parameters necessary for a therapy decision in accordance with the guidelines so that they can be considered comprehensive and completely valid apart from a few exceptions.

Needle biopsy size and pathological Gleason Score diagnosis: No evidence for a link

BACKGROUND

Biopsy Gleason score (GS), in combination with other clinical parameters, is important to take a therapeutic decision for patients with diagnosis of localized prostate cancer. However, preoperative GS is often upgraded after a radical prostatectomy. Increasing the amount of tissue in prostate biopsy may be a way to avoid this issue. We evaluate the influence of a larger biopsy needle size on the concordance between biopsy and pathological GS.

METHODS

We analyzed paired biopsies and prostatectomy specimens from 104 cases of men with clinically localized prostate cancer. At the time of prostate biopsy, the patients were prospectively randomized into two needle groups (16-Gauge [G] and 18G) using a 1:1 ratio. GS concordance was estimated performing kappa statistic testing, overall concordance rate and risk to under grade biopsy GS=6. A logistic regression analysis was performed to evaluate the patients' characteristics as possible risk factors.

RESULTS

The overall concordance between prostate biopsy and pathological GS was 76.9% and 75.6% (p = 0.875) and the k values were 0.821 and 0.811 (p = 0.424), respectively, for 16G and 18G needle study groups. The risk to undergrade a biopsy GS=6 was 21.1% and 15.4% (p = 0.709) using a 16G and 18G needle, respectively. Age, prostate-specific antigen, prostate volume and needle calibre were not independently associated with a higher risk of GS discordance.

CONCLUSIONS

Needle size does not affect the concordance between biopsy and pathological GS. Although GS is not the only way to determine treatment, it is still an unresolved urological issue.

Can a Gleason 6 or Less Microfocus of Prostate Cancer in One Biopsy and Prostate-Specific Antigen Level <10 ng/mL Be Defined as the Archetype of Low-Risk Prostate Disease?

Prostate cancer (PC) remains a cause of death worldwide. Here we investigate whether a single microfocus of PC at the biopsy (graded as Gleason 6 or less, ≤5% occupancy) and the PSA <10 ng/mL can define the archetype of low-risk prostate disease. 4500 consecutive patients were enrolled. Among them, 134 patients with a single micro-focus of PC were followed up, and the parameters influencing the biochemical relapse (BR) were analysed. Out of 134 patients, 94 had clinically significant disease, specifically in 74.26% of the patients with PSA <10 ng/mL. Positive surgical margins and the extracapsular invasion were found in 29.1% and 51.4% patients, respectively. BR was observed in 29.6% of the patients. Cox regression evidenced a correlation between the BR and Gleason grade at the retropubic radical prostatectomy (RRP), capsular invasion, and the presence of positive surgical margins. Multivariate regression analysis showed a statistically significant correlation between the presence of surgical margins at the RRP and BR. Considering a single micro-focus of PC at the biopsy and PSA serum level <10 ng/mL, clinically significant disease was found in 74.26% patients and only positive surgical margins are useful for predicting the BR.

What is the pathologist saying? Interpretation of the prostate pathology report

Management of patients presenting with elevated serum prostate-specific antigen levels, or those with previously diagnosed prostate carcinoma, is very much dependent on the pathology report on needle biopsy or radical prostatectomy specimens obtained from these patients. In contrast to a diagnosis of benignity or high-grade prostatic intraepithelial neoplasia, a diagnosis of atypia on needle core biopsy is usually an indication for a repeat biopsy; however, it is important to understand that atypia and other related terms are not specific diagnoses. The pathology report on different prostate specimens with a diagnosis of carcinoma usually includes the Gleason grade and extent of carcinoma among other morphological prognostic and predictive factors. Understanding the significance of these morphological factors and how they are evaluated and incorporated into the pathology report, as well as newer developments in this field, can assist urologists in the interpretation of the pathological findings and ultimately lead to better clinical care.

Significance of Minute Focus of Adenocarcinoma on Prostate Needle Biopsy

OBJECTIVES

To assess the radical prostatectomy findings in patients with a minute focus of adenocarcinoma on prostate needle biopsy in current practice in Australia.

METHODS

A total of 58 patients with a 0.5-mm focus or less of Gleason score 6 adenocarcinoma on needle biopsy who had been treated by radical prostatectomy were selected. At each biopsy, 6 to 20 cores (mean 11, median 13) were taken. Significant tumors were those with a Gleason score of 6 or more and tumor volume of 0.5 cm3 or larger.

RESULTS

The 58 patients (mean age 50 years, median 58, range 44 to 69) had a mean prostate-specific antigen (PSA) level of 6.9 ng/mL (range 0.7 to 16, median 6). Of the 58 men, 48 (82.75%) had pathologically significant tumor, with 8 (13.8%) showing extraprostatic extension. No statistically significant association was found between significant carcinoma and age, mean PSA level, PSA density greater than 0.15, prior negative biopsy, coexistent atypical glands, or the number of tissue cores per biopsy. A prostate weight greater than 40 g correlated significantly with insignificant cancer on both univariate (P = 0.03) and multivariate (P = 0.02) analyses. In 14 (29.2%) of 48 patients with significant tumor, the largest cancer focus in the radical prostatectomy was anterior, lateral, or anterolateral. In patients without atypical glands, 37 (78.72%) of 47 had significant carcinoma, a risk not significantly lower than that of the entire group.

CONCLUSIONS

The results of our study have shown that in populations without PSA screening, a minute focus of prostate cancer on needle biopsy, even with extended biopsy cores, does not mean insignificant carcinoma in most cases. Patients with larger glands had a greater chance of insignificant cancer.

Comparison of Gleason grade and score between preoperative biopsy and prostatectomy specimens in prostate cancer

AIM

Although the histopathological findings obtained from biopsy specimens are important for choosing the appropriate management of prostate cancer, there have been some discrepancies in Gleason grade and consequently, score between biopsy and surgical specimens. A comparison of findings between these two kinds of specimens was performed.

METHODS

Radical prostatectomy was performed at Asahi General Hospital on 223 cases of T1b-T3 without previous cancer treatment, and the Gleason grade and score of the biopsy and surgical specimens were compared.

RESULTS

A 37% coincidence in Gleason score was obtained between biopsy and surgical specimens; coincidence including one digit difference in score was approximately 70%. Upgrading was more than downgrading. Disagreement in secondary grade was greater than that in primary grade. Disagreement in Gleason score was roughly similar among different score items and was not influenced by level of prostate-specific antigen, however, the small volume of the cancer tissues more affected the discrepancy in score.

CONCLUSION

The use of biopsy findings is required to be taken into account regarding the discrepancy.

Current practice of diagnosis and reporting of prostate cancer on needle biopsy among genitourinary pathologists

As there is a lack of hard data in the literature about many of the issues relating to diagnosing and reporting prostate cancer, we sought to survey current practices. A questionnaire was sent to 93 genitourinary pathologists with a response rate of 69%. Almost all respondents (95%) used formalin as fixative for needle biopsies. Unstained intervening sections were retained by 47%. Three levels of needle biopsies were used routinely by 63%. For verification of a diagnosis of cancer, high-molecular-weight cytokeratin was still the most commonly used immunohistochemical marker (91%), followed by p63 (58%) and alpha-methylacyl-CoA-racemase (50%). Features considered pathognomonic for cancer were glomeruloid bodies (58%), collagenous micronodules (64%), circumferential perineural invasion (84%), and growth in fat (36%). With none of these present, 39% required a minimum of 2 to 10 glands (median, 3) to diagnose cancer, whereas the others had no lower limit. A Gleason score was always given to even minute cancer foci by 86% and typically a Gleason score 6 was assigned (77%). Perineural invasion was mentioned by 86%. The extent of cancer on needle biopsies was quantified by all respondents with number of involved cores (80%) being the most commonly used measure. Linear extent was estimated by almost all, either as a percentage (80%) or millimeters of cancer length (41%) or both (22%). Measuring cancer from end to end or subtracting intervening benign tissue were almost equally common. For those general pathologists who would like to be in the mainstream of most urological pathologists, our survey data provide a guideline on how to diagnose and report prostate cancer.

Current practice of Gleason grading of prostate carcinoma

The Gleason grading system remains one of the most powerful prognostic factors in prostate cancer and is the dominant method around the world in daily practice. It is based solely on the glandular architecture performed at low magnification. The Gleason grading system should be performed in needle core biopsies and radical prostatectomy specimens where it shows a reasonable degree of correlation between both specimens, and most importantly, it remains vital in the treatment decision-making process. This review summarizes the current status of Gleason grading in prostate cancer, incorporating recent proposals for the best contemporary practice of prostate cancer grading.

[Minimal prostatic adenocarcinomas in the biopsy treated with radical prostatectomy]

FUNDAMENTALS

Valuation about clinical pathologyc facts of patients having undergone a radical prostatectomy due to a minimal prostate adenocarcinoma shown at the biopsy.

METHODS

Retrospective analysis of patients having undergone a radical prostatectomy due to a minimal prostate adenocarcinoma shown at the biopsy in front of the remaining radical prostatectomies.

RESULTS

In 20 patients (7.6%) out of the 260 having undergone a radical prostatectomy between 1992 and 2004 the biopsy was informed as "minimal adenocarcinoma". These patients ranged 58 to 73 years with PSA levels from 5.2 to 17.1 ng/ml. Everyone except one were clinically T1c. At the definitive pathological study the Gleason was 6, 4, 3 and 2 in 3, 3, 8 and 4 patients respectively, with one having a minimal adenocarcinoma not graded and another one with a PIN ?. 3 showed only 1 focus with a tumoral volume less than 5% of the tissue (84.2% with significant tumor or multifocal). The final staging was 1 pT0 (PIN ?), 7 pT2a, 11 pT2b and 1 pT3a (62.5% bilaterals). Relating to the remaining patients under prostatectomy, patients with minimal adenocarcinoma presented significative differences in Gleason sum (p < 0.029) and staging (p = 0.02); no in PSA mean (p = 0.243).

SUMMARY

Minimal adenocarcinomas of the prostate at the biopsy are significant but do present lower staging and grading in relation with the rest of patients.

Gleason grading and volume estimation in prostate needle biopsy specimens: evolving issues

The Gleason grading system for prostate cancer is a powerful tool that can help choose therapy and predict outcome for patients. The clinical use and problem areas of the Gleason grading system are reviewed. The issues discussed include grade discrepancies between prostate biopsy and resection specimens, grading small foci of tumor, diagnosing and grading cribriform lesions, reporting the grade when 3 grades of cancer are present in a specimen, and assignment of grade when multiple cores of differing grades are present. Finally, differing ways of communicating tumor volume and the percentage of high-grade carcinoma in prostate biopsy cores are considered.

Gleason grading of prostate cancer in needle biopsies or radical prostatectomy specimens: contemporary approach, current clinical significance and sources of pathology discrepancies

The Gleason grading system is a powerful tool to prognosticate and aid in the treatment of men with prostate cancer. The needle biopsy Gleason score correlates with virtually all other pathological variables, including tumour volume and margin status in radical prostatectomy specimens, serum prostate-specific antigen levels and many molecular markers. The Gleason score assigned to the tumour at radical prostatectomy is the most powerful predictor of progression after radical prostatectomy. However, there are significant deficiencies in the practice of this grading system. Not only are there problems among practising pathologists but also a relative lack of interobserver reproducibility among experts.

Little or No Residual Prostate Cancer at Radical Prostatectomy: Vanishing Cancer or Switched Specimen?

With more vigilant screening for prostate cancer, there has been an associated increase in patients with little or no residual cancer at radical prostatectomy after an initial diagnosis of minute cancer on needle biopsy. This raises a critical question as to whether the biopsy and subsequent radical prostatectomy in these patients are from the same patient. We used PCR-based microsatellite marker analysis to perform identity test in 46 men (35 with minute cancer and 11 with no residual cancer). Of them, 41 were interpretable, including 31 with minute cancer and 10 with no residual cancer. All 31 interpretable cases with minute cancer showed match between the initial biopsy and radical prostatectomy specimens. Nine of the 10 interpretable cases with no residual cancer showed match and 1 showed mismatch. The remaining 5 cases (4 with minute cancer and 1 with no residual cancer) were considered uninterpretable due to technical problems. The initial biopsy of the mismatched case had high-grade cancer (Gleason score 4 + 4 = 8) measuring 9.6 mm in length with perineural invasion. Our results confirm that, in most cases of "vanishing cancer" in radical prostatectomy specimens, it reflects a chance sampling of a minute cancer and not a switch in specimens. However, specimen switch can rarely occur, and if there is high grade or a lot of cancer on the biopsy with no or very minimal cancer in the radical prostatectomy specimen, one should evaluate for patient identity.

Prostate needle biopsy reporting: how are the surgical members of the Society of Urologic Oncology using pathology reports to guide treatment of prostate cancer patients?

Recent trends in prostate needle biopsy reporting have resulted in the inclusion of more information and new diagnostic categories. The goal of the current study was to survey surgical Members of the Society of Urologic Oncology to determine what information academic urologists consider important in the management of their prostate cancer (PCa) patients. A questionnaire was developed to investigate several areas of PCa biopsy reporting, which vary from institution to institution. Urologists were sent questionnaires and asked to return anonymous responses; 42 questionnaires were completely evaluated with a response rate of 76% (42 of 55). The urologists targeted for this survey were highly experienced with an average of 22 years in clinical practice (range, 6-35 years). On average, they performed 92 radical prostatectomies per year and 449 over the past 5 years (range, 60-1500) for a group total of 18,840 radical prostatectomies; 94% have their patient's biopsy reviewed prior to surgery. The primary and secondary Gleason pattern was required by 60% (25 of 42) of the respondents. In prostate needle biopsies containing only a single minute focus of PCa, only 41% (17 of 42) of respondents would request a Gleason score if not provided in the initial report. Interestingly, in biopsies with multiple positive cores from separate locations, 81% (34 of 42) use the highest Gleason score, regardless of the overall percentage involvement, to determine their treatment plan. Other pathology parameters requested by the respondents in descending order included: % involvement of the core by PCa (67%), the presence or absence of perineural invasion (38%), the number of cores with PCa (33%), and the length of core involvement (29%). Only 24% (10 of 42) of respondents use perineural invasion status to guide nerve-sparing surgery. The more radical prostatectomies performed by a surgeon, the greater the likelihood that they considered perineural invasion clinically important (Mann-Whitney, two-tailed, P = 0.015). The term atypical small acinar proliferation was uniformly considered sufficient to re-biopsy by 98% (41 of 42) of the urologists. This is the first study to survey urologists as to what information they require from prostate needle biopsy reports in their treatment planning of men with clinically localized PCa. With the exception of Gleason score, the use of detailed pathology information was variably used to guide treatment. PNI was not considered important by the majority of respondents. In contrast, atypical small acinar proliferation, a more recent diagnostic category, was recognized as important by nearly all respondents. Knowledge of how pathology biopsy reports are being used should help evaluate what data should be uniformly part of standard biopsy pathology report and help improve communication between pathologists and urologists.

Radical prostatectomy for carcinoma of the prostate

Morphologic features of prostatic adenocarcinoma in the radical prostatectomy (RP) specimen are powerful prognostic indicators for prognosis for disease-free survival. This review discusses the methods of sampling of the RP specimen to optimize the detection of these morphologic features, balanced against the added expense of submitting the entire gland for sectioning. Gleason grade, one of the most powerful prognostic factors, is discussed briefly, including the percent pattern 4/5 cancer compared to the standard Gleason grading. Pathologic stage, as defined by the TNM system, is discussed in detail, both in terms of precise histological definition of each category, as well as the associated prognostic implications. Surgical margin status is also important prognostically across all pathologic stages categories. Perineural invasion, which has been used diagnostically in prostate cancer for several decades, has emerged as a very important prognostic indicator as well, as determined by the quantitative aspects of tumor in the perineural space. The effect of tumor volume on prognosis is discussed, as well as the newer concepts of the prognostic significance of zone of origin of the tumor and the presence or absence of intraductal carcinoma.

Representación del “score” gleason en la biopsia prostática del “score” gleason definitivo de la prostatectomía radical

INTRODUCTION

The Gleason score (Gs) for prostatic cancer has a good prognosis correlation after radical prostatectomy, for this reason its correlation with the Gs in the biopsy can be useful.

PATIENTS AND METHODS

Two hundred fifteen patients with blind evaluation among three pathologists of their Gs in biopsy and in the corresponding radical prostatectomy specimen are presented.

RESULTS

The exact coincidence is present in 49.7% of cases, 38.6% of cases are under graded in the biopsy and 11.6% of them over graded in the biopsy. No cases of Gs 2 in the biopsy are found. Any case with Gs 3 and 4 in the biopsy are reproduced in the radical prostatectomy specimen. The exact coincidence for biopsy Gs 5, 6, 7, 8 and 9 are 25%, 45%, 72.7%, 36.6% and 60% respectively (kappa 0.32 +/- 0.047, p<0.0001 in Gs 5 to 8). The Gleason pattern 4 is the less diagnosed in prostate biopsies [40% of cases with this pattern in the excision specimen it is missing in the biopsy).

CONCLUSIONS

The Gs in the needle prostatic biopsy has a good correspondence with the Gs in the radical prostatectomy specimen. For an increase of the reproducibility it is recommendable avoid the diagnosis of Gs 2, 3 and 4 in biopsy and a scrupulous search for the patterns 4 and 5.

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.

Minimal focus of adenocarcinoma on prostate biopsy: clinicopathological correlations

AIMS

To establish the clinicopathological features of minimal volume prostate adenocarcinoma on prostate biopsy.

METHODS

Twenty four cases of minimal adenocarcinoma diagnosed on prostate biopsy and treated by radical prostatectomy were reviewed.

RESULTS

The major microscopic criteria were nuclear enlargement (22 of 24), infiltrative pattern (19 of 24), prominent nucleoli (19 of 24), intraluminal eosinophilic secretions (15 of 24), and high grade intraepithelial neoplasia associated (11 of 24). Sixteen of 24 cases were assigned a Gleason score 6 on biopsy. When the whole gland was assessed, 22 of these tumours were localised to the prostate (stage pT2), and only two cases were stage pT3.

CONCLUSIONS

Minimal focus of adenocarcinoma on prostate biopsy is not an uncommon finding. It is usually an intermediate grade and localised stage neoplasm.

Interobserver reproducibility of percent Gleason grade 4/5 in total prostatectomy specimens

PURPOSE

Recently the percent Gleason grade 4/5 was proposed as a predictor of the outcome of prostate cancer and it has been shown that it adds prognostic information to that given by Gleason score. To our knowledge the interobserver variability of percent Gleason grade 4/5 has not yet been investigated. We assessed the percent Gleason grade 4/5, including the identification of high grade patterns and estimation of the percent tumor area, which is potentially more difficult than conventional Gleason grading.

MATERIALS AND METHODS

A consecutive series of 69 total prostatectomy specimens was reviewed. A single slide per specimen was circulated among 4 genitourinary pathologists, who assessed Gleason score and the percent Gleason grade 4/5. Results were compared pairwise and a weighted kappa was calculated for Gleason score and the percent Gleason grade 4/5.

RESULTS

The 4 observers had a mean weighted kappa for Gleason score and the percent Gleason grade 4/5 of 0.52 to 0.66 (overall mean 0.56) and 0.58 to 0.72 (overall mean 0.66), respectively. The best agreement for percent Gleason grade 4/5 was in 2 pathologists at the same department (weighted kappa 0.86). Transition zone tumors had a lower weighted kappa for Gleason score but a higher weighted kappa for percent Gleason grade 4/5 than peripheral zone tumors. In cases of the greatest disagreement in the percent Gleason grade 4/5 crush artifact, cribriform cancer and high grade PIN within the tumor were significantly more common. An intraobserver reproducibility of weighted kappa 0.91 was achieved for Gleason score and the percent Gleason grade 4/5.

CONCLUSIONS

Interobserver reproducibility of the percent Gleason grade 4/5 is substantial and at least as good as that of the Gleason score. Hence, concern about interobserver variability should not deter pathologists from using the percent Gleason grade 4/5 as a prognostic marker for prostate cancer.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The value of multiple core biopsies for predicting the Gleason score of prostate cancer

OBJECTIVE

To evaluate the accuracy of Gleason grading of prostate cancer in multiple core biopsies, compared with the final Gleason score of total prostatectomy specimens, and to investigate whether the prediction of the correct Gleason score is improved by increasing the number of biopsies.

PATIENTS AND METHODS

Before total prostatectomy, 121 men had a mean (range) of 10.0 (8-14) transrectal ultrasonography (TRUS)-guided core biopsies taken from the apex, mid-medial, mid-lateral and basal regions, from the transition zone and from lesions detected on TRUS. The biopsies and prostatectomy specimens were reviewed and the Gleason scores assessed.

RESULTS

The preoperative biopsies predicted the prostatectomy Gleason score exactly in 45.5% of the patients and within one Gleason score in 93.4%. The biopsies under-graded the prostate cancer in 38.8% and overgraded it in 15.7%. The weighted kappa value for exact agreement was 0.502. If one biopsy was positive for cancer, the prostatectomy Gleason score was predicted correctly in 43.8% and within one score in 93.8%, compared with 53.8% and 92.3%, respectively, if cancer was found in at least seven biopsies. If the mid-lateral and transition zone biopsies had been excluded from the biopsy protocol, 5% of the cancers would have been undetected. Among the remaining 115 cancers, grading accuracy only improved from 43.5% to 45.2% by adding biopsies to the sextant protocol.

CONCLUSION

Despite a statistically significant agreement between biopsy and prostatectomy Gleason score, under-grading remains a major problem. The prediction of the prostatectomy Gleason score is only marginally improved by increasing the number of biopsies.