Handling of radical prostatectomy specimens: total or partial embedding?

Grade Group accuracy is improved by extensive prostate biopsy sampling, but unrelated to prostatectomy specimen sampling or use of immunohistochemistry

Assessing the accurate Grade Group of a prostate needle biopsy specimen is essential for choosing the adequate therapeutic modality for prostate cancer patients. However, it is well-known that biopsy Grade Group tends to up- or downgrade significantly at radical prostatectomy. We aimed to investigate the correlation between accuracy and biopsy core number, performed immunohistochemical staining (IHC) or prostatectomy specimen sampling, with the latest also being correlated with higher detection rates of adverse pathological features, e.g., positive surgical margins, higher pathological stage or presence of perineural invasion (PnI status). The study cohort consisted of 315 consecutive patients diagnosed with prostate adenocarcinoma via transrectal ultrasound-guided needle biopsy who later underwent radical prostatectomy. We grouped and compared patients based on Grade Group accuracy, presence of IHC on biopsy, margin status, pathological stage, and PnI status. Inter-observer reproducibility was also calculated. Statistical analyzes included ANOVA, Tukey's multiple comparisons post hoc test, Chi-squared test, and Fleiss kappa statistics. Undergraded cases harboured a significantly lower number of biopsy cores (p < 0.05), than accurately graded cases. Using IHC did not affect grading accuracy significantly, nor did the number of slides from prostatectomy specimens. The mean number of slides was virtually identical when margin status, pathological stage and PnI status of prostatectomy specimens were compared. Inter-observer reproducibility at our institute was calculated as fair (overall kappa = 0.29). Grade Group accuracy is significantly improved by obtaining more cores at biopsy but is unrelated to performed IHC. The extent of sampling prostatectomy specimens, however, did not affect accuracy and failed to significantly improve detection of adverse pathological features.

[Comparison of the efficiency of surgical excision methods for detecting extraprostatic extension and positive resection margin in prostate cancer]

On the samples of 26 prostatectomies, the method of excision of the prostate gland according to Kim was tested. This method increased the number of blocks by 30.2% and increased the detectability of extraprostatic extension by 41.7% and positive surgical margin by 40.0% compared to the method of alternate prostate sections. Also, the method according to Kim reduced the number of blocks of prostate tissue by 34.3% compared to the method of complete prostate excision.

Whole slide image data utilization informed by digital diagnosis patterns

Context

Despite the benefits of digital pathology, data storage and management of digital whole slide images introduces new logistical and infrastructure challenges to traditionally analog pathology labs.

Aims

Our goal was to analyze pathologist slide diagnosis patterns to determine the minimum number of pixels required during the diagnosis.

Methods

We developed a method of using pathologist viewing patterns to vary digital image resolution across virtual slides, which we call variable resolution images. An additional pathologist reviewed the variable resolution images to determine if diagnoses could still be rendered.

Results

Across all slides, the pathologists rarely zoomed in to the full resolution level. As a result, the variable resolution images are significantly smaller than the original whole slide images. Despite the reduction in image sizes, the final pathologist reviewer could still proide diagnoses on the variable resolution slide images.

Conclusions

Future studies will be conducted to understand variability in resolution requirements between and within pathologists. These findings have the potential to dramatically reduce the data storage requirements of high-resolution whole slide images.

The impact of positive surgical margins on salvage radiation or androgen deprivation therapy following radical prostatectomy - a nationwide study

BACKGROUND

The extent to which positive surgical margins (PSM) affect the risk of subsequent salvage radiation therapy (sRT) or androgen depletion therapy (ADT) following radical prostatectomy (RP) is not well described. Initiation of additional therapies after RP depend on patient preference, individual factors, local guidelines, and life expectancy. The aim of this study was to analyze differences between margin status in risk of subsequent treatment for PCa following RP in a retrospective population-based cohort from Denmark.

METHODS

Patients who underwent RP were identified in The Danish Prostate Cancer Registry (DaPCaR). Subsequent sRT and ADT were assessed in uni- and multivariate settings and validated with receiver operating characteristic (ROC).

RESULTS

PSM was associated with an increased risk of sRT (HR = 1.85, p < .001) and receiving ADT (HR:1.39, p = .007). Margin status only had a minor impact on the predictive ability for sRT (area under the curve (AUC): p < .001) and no significant impact for subsequent ADT (AUC: p = 1). Significant inter-institutional difference in the association between PSM with sRT or ADT was observed.

CONCLUSION

PSM is associated with the risk of sRT and initiation of ADT, however this association is weak. Our results underline that factors beyond tumor characteristics play a major role for initiation of sRT and ADT.

Added Clinical Value of Whole-mount Histopathology of Radical Prostatectomy Specimens: A Collaborative Review

CONTEXT

Whole-mount histopathology, that is, large format histology or whole-mount sectioning, refers to the histopathological examination of tissue sections from specimens processed with large tissue cassette. In some institutions, it is applied routinely to specimens with genitourinary cancers.

OBJECTIVE

To give an overview of the application of the large format histology to the morphological examination of the radical prostatectomy (RP) specimens.

EVIDENCE ACQUISITION

A comprehensive PubMed search was performed up to May 2020, using the keywords "prostate carcinoma," "radical prostatectomy specimens," "whole-mount histopathology," "whole mount sectioning," "large format histology," "macrosectioning," "diagnostic criteria," and "prognosis." The search, supplemented with a hand search, was restricted to articles published in the English language. No limitations were placed on the publication year. References in relevant articles were also reviewed.

EVIDENCE SYNTHESIS

Even though the whole-mount sections of RPs appear not to be superior to regular sections in detecting adverse pathological features, their use has the advantage of displaying the architecture of the prostate gland and identifying and locating tumor nodule(s) more clearly, with particular reference to the index tumor. Further, it is easier to compare the pathological features with clinical findings derived, for instance, from digital rectal examination, transrectal ultrasound, multiparametric magnetic resonance imaging, surgical operation, and prostate biopsies.

CONCLUSIONS

Urologists, radiologists, and oncologists are updated about the step forward made by pathologists when diagnostic and prognostic information is derived from an approach that closely resembles that used by the clinicians when dealing with imaging findings.

PATIENT SUMMARY

Adoption of the whole-mount histopathology adds clinical value in correlation with clinical/imaging findings of radical prostatectomy specimens.

Partial versus complete prostatectomy specimen sampling: prospective non-inferiority study for pT3a tumours and surgical margin involvement

AIMS

The importance of additional information gained by complete versus partial sampling or prostatectomy specimens is uncertain. There is sparse data on the value of complete versus partial sampling and numbers of inclusions in studies are small and retrospective. We present the results of a prospective non-inferiority study to examine if partial sampling is inferior to complete sampling in terms of pathology outcomes and clinical relevance.

METHODS

564 robot-assisted prostatectomy (RARP) specimens with prospective registration and analysis were collected over a 2-year period. All patients underwent RARP between January 2014 and February 2016 in our hospital after a diagnosis of clinically localised prostate cancer. For each patient, tumour stage and surgical margin status was recorded after partial and after complete sampling. Upstaging from pT2 to pT3a and upgrading from a negative-to-positive surgical margin was analysed.

RESULTS

In 12 of 564 patients (2.1%), complete sampling yielded new information. In eight patients (1.4%), the surgical margin converted to positive after complete sampling. Upstaging from initial pT2 tumour in partial sampling to pT3a tumour after complete sampling was documented in five patients (0.9%). In the follow-up period (mean 35 months), a biochemical recurrence occurred in one patient.

CONCLUSIONS

Complete sampling provides new information in only 2.1% of cases, compared with partial sampling. We conclude that the additional information gained by complete sampling in terms of stage and surgical margin detection is statistically insignificant compared with partial sampling. Furthermore, partial sampling compared with complete sampling does not change postoperative clinical management.

Marked Prognostic Impact of Minimal Lymphatic Tumor Spread in Prostate Cancer

BACKGROUND

Nodal metastasis (N1) is a strong prognostic parameter in prostate cancer; however, lymph node evaluation is always incomplete.

OBJECTIVE

To study the prognostic value of lymphatic invasion (L1) and whether it might complement or even replace lymph node analysis in clinical practice.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective analysis of pathological and clinical data from 14 528 consecutive patients.

INTERVENTION

Radical prostatectomy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The impact of L1 and N1 on patient prognosis was measured with time to biochemical recurrence as the primary endpoint.

RESULTS AND LIMITATIONS

Nodal metastases were found in 1602 (12%) of 13 070 patients with lymph node dissection. L1 was seen in 2027 of 14 528 patients (14%) for whom lymphatic vessels had been visualized by immunohistochemistry. N1 and L1 continuously increased with unfavorable Gleason grade, advanced pT stage, and preoperative prostate-specific antigen (PSA) values (p<0.0001 each). N1 was found in 4.3% of 12 501 L0 and in 41% of 2027 L1 carcinomas (p<0.0001). L1 was seen in 11% of 9868 N0 and in 61% of 1360 N1 carcinomas (p<0.0001). Both N1 and L1 were linked to PSA recurrence (p<0.0001 each). This was also true for 17 patients with isolated tumor cells (ie, <200 unequivocal cancer cells without invasive growth) and 193 metastases ≤1mm. Combined analysis of N and L status showed that L1 had no prognostic effect in N1 patients but L1 was strikingly linked to PSA recurrence in N0 patients. N0L1 patients showed a similar outcome as N1 patients.

CONCLUSIONS

Analysis of lymphatic invasion provides comparable prognostic information than lymph node analysis. Even minimal involvement of the lymphatic system has pivotal prognostic impact in prostate cancer. Thus, a thorough search for lymphatic involvement helps to identify more patients with an increased risk for disease recurrence.

PATIENT SUMMARY

Already minimal amounts of tumor cells inside the lymph nodes or intraprostatic lymphatic vessels have a severe impact on patient prognosis.

Assessment of the circumferential margins, extraprostatic extension and Gleason score in radical prostatectomy specimens: Comparison of a partial embedding method with supplemental total inclusion of peripheral tissues

BACKGROUND

Recent data suggest that up to 21% of positive circumferential margins (PCM) and 47% of extraprostatic extension (EPE) samples may be missed when partial embedding methods are employed. Kim and colleagues (2009) suggested that total inclusion of the periphery (3mm rim) of the prostate prevented the failure to detect PCM and EPE.

DESIGN

Radical prostatectomy specimen (n=148) slides were reviewed after adoption of a protocol that included a ∼3 mm rim of peripheral tissues. We evaluated whether the analysis of supplemental slides of prostate periphery changed margin status, presence of EPE, Gleason score and extent of PCM and EPE.

RESULTS

Partial sampling resulted in missing 29% of PCM and 20% of EPE without using data from the supplemental slides of prostate periphery. Changes from focal to extensive disease were found in 11/21 (52%) cases of positive circumferential margins and in 5/13 (38%) cases of extraprostatic extension. Changes in the Gleason score were uncommon.

CONCLUSIONS

These results indicate the importance of including all the prostate peripheral tissue for microscopic analysis when partial embedding methods are adopted.

ERG protein expression over time: from diagnostic biopsies to radical prostatectomy specimens in clinically localised prostate cancer

Aims

We evaluated the consistency in ERG protein expression from diagnostic specimens through rebiopsies to radical prostatectomies in patients with clinically localised prostate cancer to investigate the validity of ERG status in biopsies.

Methods

ERG expression was assessed by immunohistochemistry (IHC) in 625 biopsy sets and 86 radical prostatectomy specimens from 265 patients with prostate cancer managed on active surveillance. For IHC, a rabbit monoclonal primary antibody was used (clone: EPR3864). TMPRSS2-ERG fluorescence in situ hybridisation (FISH) analyses were performed in 74 biopsies using the FISH ZytoLight TriCheck Probe (SPEC ERG/TMPRSS2). FISH results were correlated with IHC findings.

Results

The concordance between FISH and IHC was 97.3% and IHC demonstrated a sensitivity and specificity for ERG rearrangement of 100% and 95.5%, respectively. Applying IHC, 38.1% of patients were ERG-positive, 53.6% were ERG-negative and 8.3% showed both ERG-positive and negative tumour foci (ERG heterogeneous) at diagnosis. When ERG status was dichotomised (ERG-positive or heterogeneous vs ERG-negative), 95.6%–97.1% of patients did not experience ERG reclassification during the first two rounds of rebiopsies. The concordance in ERG status between biopsies and surgical specimen was 89.5%–94.2% depending on the number of rebiopsies included. Sampling bias was assumed to explain most (81.3%) of the mismatches in ERG status.

Conclusions

Consistency in ERG status ranged from 90% to 95% for patients undergoing serial biopsies and radical prostatectomy. This indicates that biopsies can be used reliably to investigate ERG's prognostic and predictive value.

Results of central pathology review of prostatic biopsies in a contemporary series from a phase III, multicenter, randomized controlled trial (SHIP0804)

To investigate contemporary rates of variation in the biopsy Gleason grading in prostate cancer, between local and central pathologists, based on central review of the pathological slides from Seed and Hormone for Intermediate-risk Prostate Cancer (SHIP) 0804, a phase III, multicenter, randomized, controlled study. From April 2008 to May 2011, 18 Japanese institutions participated. All H&E slides were reviewed independently, without clinical information, and a tumor grade was assigned according to the modified Gleason grading system proposed by the International Society of Urological Pathology (ISUP). Prostate biopsy specimens of 642 cases were available for evaluation. An exact concordance rate of Gleason score (GS) between local and central pathologists was determined to be 65.3%; with the under-grading and over-grading of grades to be 14.6% and 20.1%, respectively. The central review resulted in numbers of tumor-bearing cores reassigned in 99 of 616 cases in which such information by the local pathologists was available (16.1%). Discordance in biopsy Gleason grading was still found in one third of the cases in the SHIP0804 study. This information is valuable in extrapolating the diagnostic error range in contemporary clinical studies conducted without central pathological review.

[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.

A modified point count method as a practical approach to assess the tumor volume and the percent gland involvement by prostate carcinoma

This study reports a modified point-count method for quantifying the extent of carcinoma in prostatectomy specimens (n=143), as adapted from Billis et al. (2003) [3]. The prostates were studied as follows: the basal/apical margins were sampled using the cone method. The remainder of the gland was divided into 12 quadrant-shaped regions that were sampled using two slices. Eight equidistant points were marked directly on the coverslip over each fragment. The points inside the tumoral areas were counted and expressed as both the percentage of prostate gland involvement by carcinoma (PGI) and the tumor volume (TV). A significant correlation between the preoperative PSA levels and each of the three quantitative estimations were observed, with improved correlations with the PGI and TV values obtained using the point-count method (viz. number of slices involved (NSI) (r=0.32), PGI (r=0.39) and TV (r=0.44)). With the data sets stratified into three categories, all three methods correlated with multiple parameters, including Gleason scores ≥7, primary Gleason scores ≥4, perineural/angiolymphatic invasion, extraprostatic extension, seminal vesicle invasion and positive margins. All three quantitative methods were associated with morphologic features of tumor progression. The results obtained using this modified point-count method correlate more strongly with preoperative PSA levels.

Non-apical positive surgical margins after radical prostatectomy for pT2 prostate cancer is associated with the highest risk of recurrence

BACKGROUND AND OBJECTIVE

To investigate how location of positive surgical margins (PSM) in pT2 tumors affect the risk of biochemical recurrence (BR).

METHODS

The study includes 1,133 consecutive patients from 1995 until end of 2011, who had organ-confined disease (pT2) following RP. The location of PSM was stratified into apical and non-apical. BR was defined as the first PSA ≥ 0.2 ng/ml after RP. Risk of BR was analyzed with Kaplan-Meier and Cox regression analysis.

RESULTS

Median follow-up was 3.6 years (range: 0.5-15.5 years). The overall pT2 PSM rate was 26.3%. Overall, a pT2 with PSM had a 3.1-fold increased risk of BR compared to margin negative patients. Patients with pT2 apical and non-apical PSM had a 5-year biochemical recurrence-free survival of 84.9% (95% CI: 77.6-92.2%) and 78.6% (95% CI: 71.3-85.9%), respectively. In multivariate analysis, pT2 apical and non-apical PSM was individually associated with a 2.2- and 3.8-fold increased risk of BR compared to margin negative patients.

CONCLUSION

In our cohort the location of pT2 PSM was associated with time to BR, that is, patients with non-apical pT2 PSM endured the highest risk of BR compared to apical PSM. This may indicate that not all patients with pT2 PSM should be offered adjuvant therapy.

Risk of biochemical recurrence and positive surgical margins in patients with pT2 prostate cancer undergoing radical prostatectomy

BACKGROUND AND OBJECTIVE

To investigate risk factors associated with positive surgical margins (PSM) and biochemical recurrence (BR) in organ confined tumors (pT2) after radical prostatectomy (RP) for localized prostate cancer (PCa).

METHODS

Between 1995 and 2011, 1,649 patients underwent RP at our institution. The study includes the 1,133 consecutive patients with pT2 tumors at final histopathology. Logistic regression analysis was used for risk of PSM. Risk of BR, defined as the first PSA ≥ 0.2 ng/ml, was analyzed with Kaplan-Meier and Cox regression analysis.

RESULTS

Median follow-up was 3.6 years (range: 0.5-15.5 years). In logistic regression, NS surgery was independently associated with an increased risk of pT2 PSM (OR = 1.68, 95% CI: 1.3-2.0, P = 0.01) relative to non-NS surgery. NS surgery was not independently associated with BR but the interaction of PSM and NS surgery trended (P = 0.08) to increase the risk of BR compared to PSM and non-NS surgery.

CONCLUSION

Several factors influence the risk of pT2 PSMs in radical prostatectomy. In our cohort pT2 PSM is associated with NS surgery and trend to increase risk of BR compared to non-NS surgery. The optimal selection of candidates for NS surgery is still not clear.

Primary Gleason pattern in biopsy Gleason score 7 is predictive of adverse histopathological features and biochemical failure following radical prostatectomy

OBJECTIVE

The aim of this study was to analyse whether primary Gleason pattern in biopsy Gleason score (GS) 7 predicted adverse histopathological features and had an impact on the risk of biochemical failure in a consecutive series of patients undergoing radical prostatectomy (RP).

MATERIAL AND METHODS

Between 2006 and 2010, 441 patients with biopsy GS 7 underwent RP at Rigshospitalet, Copenhagen, Denmark. Favourable histopathological features were defined as pT2 margin-negative cancer, RP specimen GS ≤ 3+4 and no lymph-node metastasis. Adverse histopathological features were defined as advanced pT3/4 cancer or pT2 margin-positive cancer and/or RP specimen GS ≥ 4+3 and/or positive lymph nodes. Biochemical failure was defined as the first prostate-specific antigen (PSA) ≥ 0.2 ng/ml.

RESULTS

A total of 344 patients (78.0%) had GS 3+4 in biopsies, while 97 patients (22.0%) had GS 4+3. No difference in age, PSA, percentage of biopsies with cancer, clinical tumour stage or volume on transrectal ultrasonography was found. Primary Gleason pattern 4 was associated with worse pathological stage (p = 0.049). On multivariate analysis, primary Gleason pattern 4 (p < 0.0001), cT stage (p = 0.024), PSA (p < 0.0001) and age (p = 0.009) predicted adverse histopathological features. In univariate analysis, Gleason score 3+4 had a significantly lower biochemical failure rate compared with Gleason score 4+3 (p = 0.0035). PSA (p < 0.0001), primary Gleason pattern 4 (p = 0.001) and percentage of biopsies with cancer (p = 0.02) were independently associated with risk of biochemical failure.

CONCLUSIONS

In biopsies with GS 7, a primary Gleason pattern 4 was associated with significantly elevated risk of adverse histopathological features and biochemical failure compared to pattern 3 in patients undergoing RP. This study underlines the heterogeneity of biopsy GS 7.

Standardization of Gleason grading among 337 European pathologists

AIMS

  The 2005 International Society of Urological Pathology (ISUP) modification of Gleason grading recommended that the highest grade should always be included in the Gleason score (GS) in prostate biopsies. We analysed the impact of this recommendation on reporting of GS 6 versus 7.

METHODS AND RESULTS

  Fifteen expert uropathologists reached two-thirds consensus on 15 prostate biopsies with GS 6-7 cancer. Eighty-five microphotographs were graded by 337 of 617 members of the European Network of Uropathology (ENUP), representing 19 countries. There was agreement between expert and majority member GS in 12 of 15 cases, while members upgraded in three cases. Among members and the expert consensus, a GS >6 was assigned by 64.5% and 60%, respectively. Mean member GS was higher than consensus GS in nine of 15 cases. A Gleason pattern (GP) 5 was reported by 0.3-5.6% in 10 cases. Agreement between consensus and member GS was 58.2-89.3% (mean 71.4%) in GS 6 cases and 46.3-63.8% (mean 56.4%) in GS 7 cases (P = 0.009).

CONCLUSIONS

  While undergrading of prostate cancer used to be prevalent, some now tend to overgrade. Minimum diagnostic criteria for GP 4 and 5 in biopsies need to be better defined. Image libraries reviewed by experts may be useful for standardization.

Is it possible to predict low-volume and insignificant prostate cancer by core needle biopsies?

In an attempt to minimize overtreatment of localized prostate cancer (PCa) active surveillance (AS) and minor invasive procedures have received increased attention. We investigated the accuracy of pre-operative findings in defining insignificant disease and distinguishing between unilateral/unifocal and bilateral/multifocal PCa. One-hundred and sixty patients undergoing radical prostatectomy were included. Histology reports from the biopsies and matching prostatectomies were compared. Three definitions of insignificant cancer were used: InsigE: tumour volume ≤0.5 mL; InsigW: tumour volume ≤1.3 mL; InsigM: tumour ≤5% of total prostate volume and prostate-specific antigen (PSA) ≤10 ng/mL. In all definitions, Gleason score (GS) was ≤6 and the tumour was organ confined. Biopsies alone performed poorly as a predictor of unifocal and unilateral cancer in the prostatectomy specimens with positive predictive values of 17.8% and 18.9% respectively. Inclusion of other clinical and biochemical parameters did not significantly increase the predictive value. However, the combination of GS ≤ 6, PSA ≤ 10 ng/mL and unifocal or unilateral cancer in biopsy cores resulted in a positive predictive value of 61.1%, 38.9% and 12.0%, respectively, for identifying InsigM, InsigW and InsigE in the prostate specimen. Conclusively, routine prostate biopsies cannot predict unifocal and unilateral PCa, and must be regarded insufficient to select patients for focal therapy. Although candidates for AS may be identified using standard biopsies, a considerable fraction of patients will be understaged. There is a need for more precise diagnostic tools to assess intraprostatic tumour growth.

Handling of radical prostatectomy specimens: total embedding with large-format histology

A problem when handling radical prostatectomy specimens (RPS) is that cancer is often not visible at gross examination, and the tumor extent is always underestimated by the naked eye. The challenge is increased further by the fact that prostate cancer is a notoriously multifocal and heterogeneous tumor. For the pathologist, the safest method to avoid undersampling of cancer is evidently that the entire prostate is submitted. Even though whole mounts of sections from RPS appear not to be superior to sections from standard blocks in detecting adverse pathological features, their use has the great advantage of displaying the architecture of the prostate and the identification and location of tumour nodules more clearly, with particular reference to the index tumour; further, it is easier to compare the pathological findings with those obtained from digital rectal examination (DRE), transrectal ultrasound (TRUS), and prostate biopsies. We are in favour of complete sampling of the RPS examined with the whole mount technique. There are reasons in favour and a few drawbacks. Its implementation does not require an additional amount of work from the technicians' side. It gives further clinical significance to our work of uropathologists.

Implications of the International Society of Urological Pathology modified Gleason grading system

CONTEXT

Histologic grading is the clinically most useful tissue-based predictor of prognosis for prostate cancer. Over the years, there has been a gradual shift in how the Gleason grading is applied in practice, with a general trend toward upgrading. A consensus conference was organized in 2005 by the International Society of Urological Pathology (ISUP) for standardizing both the perception of histologic patterns and how the grade information is compiled and reported.

OBJECTIVE

To review the implications of the ISUP modified Gleason grading system.

DATA SOURCES

Personal experience and review of the current literature.

CONCLUSIONS

The recommendations regarding pattern interpretation and reporting are summarized. The practical consequences of the ISUP modification of the Gleason grading are reported. The prognostic importance of the Gleason score, its reproducibility, and its preoperative assessment are discussed. Subsequent proposals for slight modifications to the ISUP grading system are described.

Processing radical prostatectomies: an alternate-slice method is comparable with total embedding

Receipt of radical prostatectomy specimens in the histopathology laboratory is quite common in academic centers and community hospitals. Despite numerous processing protocols, there is not an accepted standard method of processing. There are potential disadvantages of total sampling of the prostate; however, other alternatives have not been proven to show significant advantages. We present a partial sampling method (alternate slice) and compare its results to the total embedding method. Consecutive radical prostatectomy specimens were selected to compare both histologic sampling methods. The primary method of sampling was total embedding. Subsequently, alternate slice sections from the anterior, middle, and posterior thirds of the gland were reviewed. Seminal vesicle, bladder neck, and margins were similarly evaluated in both methods. Total sampling resulted in an average of 30 blocks compared with 18 in the alternate slice method. Gleason correlation was 87.5%; extraprostatic extension correlation was 97.9%. There was complete correlation in margin status and perineural invasion. Pathologic staging correlation was 97.9%. In summary, this alternate slice method compares very favorably with the total embedding method.