Correlation between tumor extent in radical prostatectomies and preoperative PSA, histological grade, surgical margins, and extraprostatic extension: application of a new practical method for tumor extent evaluation

Multiple analyses suggests texture features can indicate the presence of tumor in the prostate tissue

Several studies have demonstrated statistical and texture analysis abilities to differentiate cancerous from healthy tissue in magnetic resonance imaging. This study developed a method based on texture analysis and machine learning to differentiate prostate findings. Forty-eight male patients with PI-RADS classification and subsequent radical prostatectomy histopathological analysis were used as gold standard. Experienced radiologists delimited the regions of interest in magnetic resonance images. Six different groups of images were used to perform multiple analyses (seven analyses variations). Those analyses were outlined by specialists in urology as those of most significant importance for the classification. Forty texture features were extracted from each image and processed with Random Forest, Support Vector Machine, K-Nearest Neighbors, and Naive Bayes. Those seven analyses variation results were described in terms of area under the ROC curve (AUC), accuracy, F-score, precision and sensitivity. The highest AUC (93.7%) and accuracy (88.8%) were obtained when differentiating the group with both MRI and histopathology positive findings against the group with both negative MRI and histopathology. When differentiating the group with both MRI and histopathology positive findings versus the peripheral image zone group the AUC value was 86.6%. When differentiating the group with negative MRI/positive histopathology versus the group with both negative MRI and histopathology the AUC value was 80.7%. The evaluation of statistical and texture analysis promoted very suggestive indications for future work in prostate cancer suspicious regions. The method is fast for both region of interest selection and classification with machine learning and the result brings original contributions in the classification of different groups of patients. This tool is low-cost, and can be used to assist diagnostic decisions.

Biopsy core length in white versus African descendant prostate cancer patients

Objective: To explore whether distinct prostate cancer (PCa) prognoses between ethnicities could be explained by diverse characteristics in the prostate biopsy.Methods: Clinical, prostate biopsy and surgical single-institution data of whites and African descendants with similar access to the health system who underwent radical prostatectomy whole gland histopathology within 60 days after biopsy from 2010 to 2011 and followed for 5 years minimum were compared.Results: Among 203 included patients, 153 (75.4%) were whites and 50 (24.6%) were African descendants. The mean patients' age was 63.7 (± 6.8) years. Digital rectal examination (DRE) was suspected of cancer in 45.2% of the patients. The prostate biopsy core length was smaller in African descendants than in whites, overall 11.0 ± 3.2 vs 12.0 ± 2.9 mm, p = 0.037, and without neoplasia, 10.4 ± 3.8 vs 11.7 ± 3.1 mm, p = 0.038, respectively. Also, suspicious DRE showed smaller biopsy core length, overall 11.1 ± 3.2 mm vs 12.4 ± 2.6, p = 0.003, cancer positive 12.0 ± 4.8 mm vs 13.3 ± 3.7, p = 0.022 and negative 10.6 ± 3.6 mm vs 12.2 ± 3.0, p = 0.002. On 81 months median follow-up, more African descendants were lost to follow-up (10%, n = 5 vs 3.9%, n = 6) and the biochemical recurrence rate was the same between the groups (33.3%).Conclusion: In a PCa population with similar access to the health system, prostate biopsy core length in African descendant men is significantly smaller than in whites. This finding is new and may add to the controversial argument of PCa having a worse prognosis in African descendant patients.

In Organ-confined Prostate Cancer, Tumor Quantitation Not Found to Aid in Prediction of Biochemical Recurrence

In the eighth edition AJCC staging, all organ-confined disease is assigned pathologic stage T2, without subclassification. We investigated whether total tumor volume (TTV) and/or maximum tumor diameter (MTD) of the index lesion are useful in improving prediction of biochemical recurrence (BCR) in pT2 patients. We identified 1657 patients with digital tumor maps and quantification of TTV/MTD who had pT2 disease on radical prostatectomy (RP). Multivariable Cox regression models were used to assess whether TTV and/or MTD are independent predictors of BCR when adjusting for a base model incorporating age, preoperative prostate-specific antigen, RP grade group, and surgical margin status. If either tumor quantification added significantly, we calculated and reported the c-index. Ninety-five patients experienced BCR after RP; median follow-up for patients without BCR was 5.7 years. The c-index was 0.737 for the base model. Although there was some evidence of an association between TTV and BCR (P=0.088), this did not meet conventional levels of statistical significance and only provided a limited increase in discrimination (0.743; c-index improvement: 0.006). MTD was not associated with BCR (P>0.9). In analyses excluding patients with grade group 1 on biopsy who would be less likely to undergo RP in contemporary practice (622 patients; 59 with BCR), TTV/MTD was not a statistically significant predictor (P=0.4 and 0.8, respectively). Without evidence that tumor quantitation, in the form of either TTV or MTD of the index lesion, is useful for the prediction of BCR in pT2 prostate cancer, we cannot recommend its routine reporting.

The TNM 8th edition: Validation of the proposal for organ - confined (pT2) prostate cancer

Purpose:

The 8^th edition of the TNM has been updated and improved in order to ensure a high degree of clinical relevance. A major change in prostate includes pathologically organ - confined disease to be considered pT2 and no longer subclassified by extent of involvement or laterality. The aim of this study was to validate this major change.

Materials and Methods:

Prostates were step - sectioned from 196 patients submitted to radical prostatectomy with organ confined disease (pT2) and negative surgical margins. Tumor extent was evaluated by a semiquantitative point count method. The dominant nodule extent was recorded as the maximal number of positive points of the largest single focus of cancer from the quadrants. Laterality was considered as either total tumor extent (Group 1) or index tumor extent (Group 2). Time to biochemical recurrence was analyzed with the Kaplan - Meier product limit analysis and prediction of shorter time to biochemical recurrence with Cox proportional hazards model.

Results:

In Group 1, 43 / 196 (21.9%) tumors were unilateral and 153 / 196 (78.1%) bilateral and in Group 2, 156 / 196 (79.6%) tumors were unilateral and 40 / 196 (20.4%) bilateral. In both groups, comparing unilateral vs bilateral tumors, there was no significant clinicopathological difference, and no significant association with time as well as prediction of shorter time to biochemical recurrence following surgery.

Conclusions:

Pathologic sub - staging of organ confined disease does not convey prognostic information either considering laterality as total tumor extent or index tumor extent. Furthermore, no correlation exists between digital rectal examination and pathologic stage.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

A Novel System for Estimating Residual Disease and Pathologic Response to Neoadjuvant Treatment of Prostate Cancer

BACKGROUND

Pathologic variables that characterize response of prostate carcinoma to current neoadjuvant therapy have not been characterized in detail. This study reports (i) the histological features of prostate cancer treated with abiraterone and enzalutamide and inter-pathologist variance in identifying these features, and (ii) the effect of the novel androgen deprivation agents on residual cancer volume.

METHODS

We reviewed sections of prostatectomies from 37 patients treated with neoadjuvant agents and 22 untreated patients, tabulated the frequency of nine features of cancer (intact cancer glands, isolated cancer cells, poorly formed glands, cribriform architecture, clear spaces, intraductal carcinoma, solid sheets of cancer cells, prominent nucleoli, and previously described ABC grouping) and two features of benign glands (prominent basal cells and coalescent corpora amylacea). We used several methods, including a novel metric (visual grid system), to estimate residual tumor volume.

RESULTS

The most highly reproducible features were ABC grouping (κ = 0.56-0.7), presence of intraductal carcinoma (κ = 0.34-0.72), cribriform architecture (κ = 0.42-0.68), solid sheets of tumor cells (κ = 0.44-0.56), and coalescent corpora amylacea (κ = 0.4-0.54). Among poorly reproducible features were prominent nucleoli (κ = 0.03-0.11), clear spaces (κ = 0.05-0.07), and poorly formed cancer glands (κ = 0.02-0.1). Determination of tumor mass was excellent regardless of the method used-maximum tumor size (κ = 0.9-0.94), tumor area (κ = 0.94-0.96), and grid-based tumor cellularity (κ = 0.9).

CONCLUSIONS

We propose using a set of parameters including maximum tumor size, tumor area/volume, cellularity, volume, and ABC grouping for evaluating radical prostatectomies post-neoadjuvant therapy. Prostate 76:1285-1292, 2016. © 2016 Wiley Periodicals, Inc.

Predictive criteria of insignificant prostate cancer: what is the correspondence of linear extent to percentage of cancer in a single core?

Objective

The aim of active surveillance of early prostate cancer is to individualize therapy by selecting for curative treatment only patients with significant cancer. Epstein’s criteria for prediction of clinically insignificant cancer in surgical specimens are widely used. Epstein’s criterion “no single core with >50% cancer” has no correspondence in linear extent. The aim of this study is to find a possible correspondence.

Materials and Methods

From a total of 401 consecutive patients submitted to radical prostatectomy, 17 (4.2%) met criteria for insignificant cancer in the surgical specimen. The clinicopathologic findings in the correspondent biopsies were compared with Epstein’s criteria for insignificant cancer. Cancer in a single core was evaluated in percentage as well as linear extent in mm.

Results

Comparing the clinicopathologic findings with Epstein’s criteria predictive of insignificant cancer, there was 100% concordance for clinical stage T1c, no Gleason pattern 4 or 5, ≤2 cores with cancer, and no single core with >50% cancer. However, only 25% had density ≤0.15. The mean, median and range of the maximum length of cancer in a single core in mm were 1.19, 1, and 0.5-2.5, respectively. Additionally, the mean, median, and range of length of cancer in all cores in mm were 1.47, 1.5, and 0.5-3, respectively.

Conclusion

To pathologists that use Epstein’s criteria predictive of insignificant cancer and measure linear extent in mm, our study favors that “no single core with >50% cancer” may correspond to >2.5 mm in linear extent.

Controversial predictors of biochemical recurrence after radical prostatectomy: a study from a Latin American (Brazilian) institution

PURPOSE

To analyze controversial clinicopathologic predictors of biochemical recurrence after surgery: age, race, tumor extent on surgical specimen, tumor extent on needle biopsy, Gleason score 3 + 4 vs 4 + 3, and amount of extent of extraprostatic extension and positive surgical margins.

MATERIALS AND METHODS

The needle biopsies and the correspondent surgical specimens were analyzed from 400 patients. Time to recurrence was analyzed with the Kaplan-Meier curves and risk of shorter time to recurrence using Cox univariate and multivariate analysis.

RESULTS

Except for age, race, maximum percentage of cancer per core, and number of cores with cancer, all other variables studied were significantly predictive of time to biochemical recurrence using the Kaplan-Meier curves. In univariate analysis, except for focal extraprostatic extension, age, race, focal positive surgical margins, and maximum extent and percentage of cancer per core, all other variables were significantly predictive of shorter time to recurrence. On multivariate analysis, diffuse positive surgical margins and preoperative PSA were independent predictors.

CONCLUSIONS

Young patients and non-whites were not significantly associated with time to biochemical recurrence. The time consuming tumor extent evaluation in surgical specimens seems not to add additional information to other well established predictive findings. The higher predictive value of Gleason score 4 + 3 = 7 vs 3 + 4 = 7 discloses the importance of grade 4 as the predominant pattern. Extent and not simply presence or absent of extraprostatic extension should be informed. Most tumor extent evaluations on needle biopsies are predictive of time to biochemical recurrence, however, maximum percentage of cancer in all cores was the strongest predictor.

Supporting prostate cancer focal therapy: a multidisciplinary International Consensus of Experts ("ICE")

Prostate cancer is a common malignancy among men, and the current screening, imaging and sampling approaches aim to detect early-stage, organ-confined disease. In such scenario, focal prostate cancer therapy currently relies on the index lesion concept as the dominant lesion that drives the disease natural history. Focal therapy demands the essential imaging and sampling techniques to strategically locate and qualify the disease, but, despite advances in technology, prostate imaging and biopsy have several limitations that need to be overcome if focal therapy is to be developed further. The I Prostate Cancer Focal Treatment International Symposium was convened to foster discussion on this topic that sits at the crossroads of multiple disciplines (Urology, Pathology, Radiology, Radiation Oncology and Medical Oncology) all of which were represented for this comprehensive multidisciplinary review of the current literature.

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.

Higher prostate weight is inversely associated with Gleason score upgrading in radical prostatectomy specimens

Background. Protective factors against Gleason upgrading and its impact on outcomes after surgery warrant better definition. Patients and Methods. Consecutive 343 patients were categorized at biopsy (BGS) and prostatectomy (PGS) as Gleason score, ≤6, 7, and ≥8; 94 patients (27.4%) had PSA recurrence, mean followup 80.2 months (median 99). Independent predictors of Gleason upgrading (logistic regression) and disease-free survival (DFS) (Kaplan-Meier, log-rank) were determined. Results. Gleason discordance was 45.7% (37.32% upgrading and 8.45% downgrading). Upgrading risk decreased by 2.4% for each 1 g of prostate weight increment, while it increased by 10.2% for every 1 ng/mL of PSA, 72.0% for every 0.1 unity of PSA density and was 21 times higher for those with BGS 7. Gleason upgrading showed increased clinical stage (P = 0.019), higher tumor extent (P = 0.009), extraprostatic extension (P = 0.04), positive surgical margins (P < 0.001), seminal vesicle invasion (P = 0.003), less “insignificant” tumors (P < 0.001), and also worse DFS, χ² = 4.28, df = 1, P = 0.039. However, when setting the final Gleason score (BGS ≤6 to PGS 7 versus BGS 7 to PGS 7), avoiding allocation bias, DFS impact is not confirmed, χ² = 0.40, df = 1, P = 0.530.Conclusions. Gleason upgrading is substantial and confers worse outcomes. Prostate weight is inversely related to upgrading and its protective effect warrants further evaluation.

Influence of focal and diffuse extraprostatic extension and positive surgical margins on biochemical progression following radical prostatectomy

PURPOSE

The amount of extraprostatic extension and positive surgical margin correlates in most studies with biochemical recurrence following radical prostatectomy. We studied the influence of focal and diffuse extraprostatic extension and positive surgical margins on biochemical progression using a simple method for quantification.

MATERIALS AND METHODS

A total of 360 prostates were step-sectioned and totally processed from 175 patients with stage T1c and 185 patients with clinical stage T2 submitted to radical retropubic prostatectomy. Extraprostatic extension was stratified into 2 groups: present up to 1 quadrant and/or section from the bladder neck or apex (Group 1, focal) and in more than 1 quadrant or section (Group 2, diffuse); and, positive surgical margin present up to 2 quadrants and/or sections (Group 1, focal) and in more than 2 quadrants or sections (Group 2, diffuse). The Kaplan-Meier product-limit analysis was used for the time to biochemical recurrence, and an univariate and multivariate Cox stepwise logistic regression model to identify significant predictors.

RESULTS

Extraprostatic extension was found in 129/360 (35.8%) patients, 39/129 (30.2%) in Group 1 and 90/129 (69.8%) in Group 2. In univariate analysis but not in multivariate analysis, patients showing diffuse extraprostatic extension (Group 2) had a significant higher risk to develop biochemical recurrence in a shorter time. Positive surgical margin was present in 160/360 (44.4%) patients, 81/160 (50.6%) patients in Group 1 and 79/160 (49.4%) patients in Group 2. Patients with diffuse positive surgical margins (Group 2) had a significant higher risk in both univariate and multivariate analyses. Diffuse positive surgical margin was the strongest predictor on both analyses and an independent predictor on multivariate analysis.

CONCLUSION

Diffuse extraprostatic extension in univariate analysis and positive surgical margins on both univariate and multivariate analyses are significant predictors of shorter time to biochemical progression following radical prostatectomy.

The ability of prostate-specific antigen (PSA) density to predict an upgrade in Gleason score between initial prostate biopsy and prostatectomy diminishes with increasing tumour grade due to reduced PSA secretion per unit tumour volume

Study Type - Diagnostic (exploratory cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Due to sampling error, the Gleason score of clinically localized prostate cancer is frequently underestimated at the time of initial biopsy. Given that this may lead to inappropriate surveillance of patients with high-risk disease, there is considerable interest in identifying predictors of significant undergrading. Recently PSAD has been proposed to be an accurate predictor of subsequent upgrading in patients diagnosed with Gleason 6 disease on biopsy. We examined the predictive characteristics of PSAD in patients with low- and intermediate-risk disease on biopsy subsequently treated with radical prostatectomy. We found that although PSAD was a significant predictor of upgrade of biopsy Gleason 6 and 3 + 4 = 7 tumours, it failed to predict upgrading in patients with Gleason 7 tumours taken as a whole. When we explored reasons for this discrepancy, we found that the amount of PSA produced per unit tumour volume decreased with increasing Gleason score, thereby diminishing the predictive value of PSAD.

OBJECTIVES

To analyse the performance of PSA density (PSAD) as a predictor of Gleason score upgrade in a large cohort stratified by Gleason score. We and others have shown that an upgrade in Gleason score between initial prostate biopsy and final radical prostatectomy (RP) pathology is a significant risk factor for recurrence after local therapy.

PATIENTS AND METHODS

Patients undergoing RP with matching biopsy information were identified from two prospective databases. Patients were analysed according to the concordance between biopsy and final pathology Gleason score in three paired groups: 6/>6, 3 + 4/>3 + 4, 7/>7. Receiver-operating characteristic (ROC) curves were generated stratified by Gleason score, and the area under the curve (AUC) calculated. Logistic regression models were fitted to identify significant predictors of tumour upgrade.

RESULTS

From 1516 patients, 435 (29%) had an upgrade in Gleason score. ROC analysis showed a decline in AUC with increasing biopsy Gleason score, from 0.64 for biopsy Gleason score 6, to 0.57 for Gleason score 7. In logistic regression models containing pretreatment variables, e.g. clinical stage and number of positive cores, for Gleason score 6 and 3 + 4, PSAD was the strongest predictor of subsequent tumour upgrade (odds ratio [OR] 1.46, 95% confidence interval [95% CI] 1.18-1.83, P= 0.001 and OR 1.37, 95% CI 1.14-1.67, P= 0.002, respectively). Surprisingly, in tumours upgraded from Gleason score 7 to >7, PSAD was not predictive even on univariable analysis, whereas clinical stage and number of positive cores were significant independent predictors. To explore the relationship between serum PSA and Gleason score, tumour volume was calculated in 669 patients. There was a strong association between Gleason score and tumour volume, with the median volume of Gleason score 7 and Gleason score >7 tumours being approximately twice and four-times that of Gleason score 6 tumours, respectively (P < 0.001). In contrast, the median serum PSA level per millilitre tumour volume decreased significantly with increasing grade, from 5.4 ng/mL for Gleason score 6 to 2.1 ng/mL for >7 (P < 0.001).

CONCLUSIONS

There is a strong correlation between Gleason score and tumour volume in well/intermediate differentiated tumours, and as they produce relatively high amounts of PSA per unit volume of cancer, high PSAD is the strongest single predictor of tumour undergrading. However, as higher grade tumours produce less PSA per unit volume, PSAD loses its predictive ability, and other clinical markers of tumour volume such as palpable disease and numbers of positive cores become more predictive.

International Society of Urological Pathology (ISUP) Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens. Working group 2: T2 substaging and prostate cancer volume

The 2009 International Society of Urological Pathology consensus conference in Boston made recommendations regarding the standardization of pathology reporting of radical prostatectomy specimens. Issues relating to the substaging of pT2 prostate cancers according to the TNM 2002/2010 system, reporting of tumor size/volume and zonal location of prostate cancers were coordinated by working group 2. A survey circulated before the consensus conference demonstrated that 74% of the 157 participants considered pT2 substaging of prostate cancer to be of clinical and/or academic relevance. The survey also revealed a considerable variation in the frequency of reporting of pT2b substage prostate cancer, which was likely a consequence of the variable methodologies used to distinguish pT2a from pT2b tumors. Overview of the literature indicates that current pT2 substaging criteria lack clinical relevance and the majority (65.5%) of conference attendees wished to discontinue pT2 substaging. Therefore, the consensus was that reporting of pT2 substages should, at present, be optional. Several studies have shown that prostate cancer volume is significantly correlated with other clinicopathological features, including Gleason score and extraprostatic extension of tumor; however, most studies fail to demonstrate this to have prognostic significance on multivariate analysis. Consensus was reached with regard to the reporting of some quantitative measure of the volume of tumor in a prostatectomy specimen, without prescribing a specific methodology. Incorporation of the zonal and/or anterior location of the dominant/index tumor in the pathology report was accepted by most participants, but a formal definition of the identifying features of the dominant/index tumor remained undecided.

Relationship of age to outcome and clinicopathologic findings in men submitted to radical prostatectomy

OBJECTIVE

It is controversial whether age is associated with higher grade and worse outcome. Some studies have not found age to be related to outcome nor younger age to be associated with better response to therapy.

MATERIALS AND METHODS

The study population consisted of 27 patients aged 55 years or younger and 173 patients 56 years or older submitted to radical prostatectomy. The variables studied were preoperative PSA, time to PSA progression following radical prostatectomy and pathologic findings in surgical specimens: Gleason score, Gleason predominant grade, positive surgical margins, tumor extent, extraprostatic extension (pT3a), and seminal vesicle invasion (pT3b).

RESULTS

Comparing patients aged 55 years or younger and 56 years or older, there was no statistically significant difference for all variables studied: preoperative PSA (p = 0.4417), Gleason score (p = 0.3934), Gleason predominant grade (p = 0.2653), tumor extent (p = 0.1190), positive surgical margins (p = 0.8335), extraprostatic extension (p = 0.3447) and seminal vesicle invasion (p > 0.9999). During the study period, 44 patients (22%) developed PSA progression. No difference was found in the time to biochemical progression between men aged 55 years or younger and 56 years or older.

CONCLUSIONS

Our findings suggest that age alone do not influence the biological aggressiveness of prostate cancer.

Are prostate carcinoma clinical stages T1C and T2 similar?

PURPOSE

A recent study has found that PSA recurrence rate for clinical T1c tumors is similar to T2 tumors, indicating a need for further refinement of clinical staging system. To test this finding we compared clinicopathologic characteristics and the time to PSA progression following radical retropubic prostatectomy of patients with clinical stage T1c tumors to those with stage T2, T2a or T2b tumors.

MATERIALS AND METHODS

From a total of 186 consecutive patients submitted to prostatectomy, 33.52% had clinical stage T1c tumors, 45.45% stage T2a tumors and 21.02% stage T2b tumors. The variables studied were age, preoperative PSA, prostate weight, Gleason score, tumor extent, positive surgical margins, extraprostatic extension (pT3a), seminal vesicle invasion (pT3b), and time to PSA progression. Tumor extent was evaluated by a point-count method.

RESULTS

Patients with clinical stage T1c were younger and had the lowest mean preoperative PSA. In the surgical specimen, they had higher frequency of Gleason score < 7 and more organ confined cancer. In 40.54% of the patients with clinical stage T2b tumors, there was extraprostatic extension (pT3a). During the study period, 54 patients (30.68%) developed a biochemical progression. Kaplan-Meier product-limit analysis revealed no significant difference in the time to PSA progression between men with clinical stage T1c versus clinical stage T2 (p = 0.7959), T2a (p = 0.6060) or T2b (p = 0.2941) as well as between men with clinical stage T2a versus stage T2b (p = 0.0994).

CONCLUSION

Clinicopathological features are not similar considering clinical stage T1c versus clinical stages T2, T2a or T2b.

Prostate cancer pathologic stage pT2b (2002 TNM staging system): does it exist?

OBJECTIVE

In the 1997 TNM staging system, tumors were classified into a single subdivision: T2a, and bilateral tumor involvement (T2b). In the 2002 TNM staging system, tumors are subclassified as T2a (less than one half of one lobe involvement), T2b (more than one half of one lobe involvement), and T2c (bilateral involvement). A recent study questioned the existence of a true pathologic pT2b tumor. The aim of our study is to verify this question.

MATERIALS AND METHODS

The study population consisted of 224 men submitted to radical retropubic prostatectomy. The surgical specimens were histologically evaluated by complete embedding and whole-mount processing. Tumor extent was evaluated by a point-count method. The surgical specimens were staged according to the 2002 TNM staging system.

RESULTS

Using the 2002 TNM criteria, the surgical specimens were classified as pT2a, 28 (12.50%); pT2b, 0 (0%); pT2c, 138 (61.61%); pT3a, 30 (13.39%); and, pT3b, 28 (12.50%). Using the point-count method for tumor extent evaluation, the minimum and maximum total points obtained in unilateral tumors were 192 and 368 points, respectively; the most extensive unilateral tumor showed 68 positive points (less than half the minimum total point-count).

CONCLUSIONS

Using the point-count method for tumor extent, our study questions a real existence for pathologic stage pT2b tumors (unilateral tumors involving greater than one-half of one lobe).