Percent Tumor Involvement and Risk of Biochemical Progression After Radical Prostatectomy

Nomogram for predicting the biochemical recurrence of prostate cancer after neoadjuvant androgen deprivation therapy

BACKGROUND

A predictive model for biochemical recurrence (BCR) of prostate cancer (PCa) after neoadjuvant androgen deprivation therapy (nADT) has not been established. This study was aimed at determining multiparameter variables that could be used to construct a nomogram to predict the post-nADT BCR of PCa.

METHODS

Overall, 43 radical prostatectomy specimens from PCa patients who had undergone nADT were collected. Multiparameter variables were analyzed by univariate and then multivariate logistic analyses to identify the independent prognostic factors for predicting BCR. The predictive model was established using Lasso regression analysis.

RESULTS

Univariate logistic analysis revealed six variables, pathology stage; margins; categorization as group A, B, or C; nucleolus grading; percentage of tumor involvement (PTI); and PTEN status were significantly associated with the BCR of PCa (all p < 0.05). Multivariate logistic regression analysis suggested that categorization as group C, severe nucleolus grading, PTI less than or equal to 5%, and PTEN loss were positively correlated with BCR (all p < 0.05). A nomogram comprising the four variables predicting BCR was constructed, and it exhibited good discrimination (AUC: 0.985; specificity: 86.2%; sensitivity: 100%). Calibration plots for the probability of freedom from BCR at 1 and 2 years showed a good match between the prediction by the nomogram.

CONCLUSIONS

We constructed and validated a nomogram to predict the risk of BCR in PCa patients after nADT. This nomogram is a complement to the existing risk stratification systems for PCa, which could have marked implications for clinical decision-making for PCa patients after nADT.

The tumor volume after radical prostatectomy and its clinical impact on the prognosis of patients with localized prostate cancer

We evaluated the contribution of tumor volume (TV) to localized prostate cancer (PCa) patients’ prognosis. We retrospectively analyzed the data of 2394 patients who underwent radical prostatectomy (RP) for localized PCa. The effect of TV and tumor prostate ratio (TV/PV) on PCa patients' prognosis was analyzed through Kaplan–Meier and Cox-proportional analysis. The mean prostate volume for all patients was 36.5 ± 15.4 cc, and the mean TV was 5.9 ± 8.3 cc. A significant positive relationship was observed between the classification by risk group in D’ Amico risk classification and the National Comprehensive Cancer Network risk group (P < 0.001). The high TV showed significantly worse pathologic outcomes than the low TV in terms of high rates of extra-capsular extension, seminal vesicle invasion, and positive surgical margin (P < 0.05). The patients with high TV and TV/PV had significantly shorter biochemical recurrence-free survivals than those with low TV and TV/PV (P < 0.001). Finally, based on multivariate Cox-proportional analyses, TV and TV/PV was an independent predictor to predict shorter biochemical recurrence-free survival as both a TV (HR: 1.04, 95% CI 1.04–1.05, P < 0.001) and TV/PV (HR: 1.42, 95% CI 1.13–1.78, P = 0.003). TV was revealed to be an independent prognostic factor in the postoperative biochemical recurrence. Patients with a high number of positive core and longer tumor length were significantly related to higher TV.

Impact of the Proportion of Biopsy Positive Core in Predicting Biochemical Recurrence in Patients with Pathological Pt2 and Negative Resection Margin Status after Radical Prostatectomy

This study aimed to determine the prognostic factors associated with biochemical recurrence (BCR) after radical prostatectomy (RP) in patients with pathological T2 (pT2) prostate cancer (PCa) and negative resection margin (RM) status at a single institution. In this retrospective study, we examined 386 patients who were diagnosed with pT2 PCa with negative RM after RP. The length of the tumor was provided for each biopsy core and the overall percentage of PCa was calculated by a pathologist at our institution. We estimated the BCR-free survival (BRFS) in these patients. Univariate and multivariate analyses were performed using the Cox proportional hazard model to determine the risk factors of BCR. The median age of the participants was 68 years, and their initial prostate-specific antigen level was 6.55 ng/mL. The median follow-up period was 85.7 months. The 5-year BRFS rate of the participants was 89.0%. The 5-year BRFS rates were 89.8% in patients with a biopsy Gleason score of 6, 90.4% in those with 7, and 64.1% in those with ≥8 (P = 0.007). The BRFS rate was 93.3% in patients who had a biopsy positive core ≤20% and 82.0% in those who had ≥21% (P = 0.001). Based on the multivariate analysis, the proportion of biopsy positive core was significantly associated with BCR. The proportion of biopsy positive core may predict preoperative covariates in patients with pT2 PCa and negative RM status after RP.

Clinical Usefulness of Prostate and Tumor Volume Related Parameters following Radical Prostatectomy for Localized Prostate Cancer

PURPOSE

We evaluated whether the prediction of biochemical recurrence after radical prostatectomy is enhanced by any of 6 parameters, including prostate volume, total tumor volume, high grade total tumor volume, the ratio of high grade total tumor volume to total tumor volume, the ratio of total tumor volume to prostate volume and/or the ratio of high grade total tumor volume to prostate volume.

MATERIALS AND METHODS

A total of 1,261 patients who underwent radical prostatectomy during a 3-year period had tumor maps constructed with the Gleason pattern denoted as low-3 or high-4 or 5 and volumetric data generated using commercially available software. Univariate Cox regression models were used to assess whether each volume related parameter was associated with biochemical recurrence after radical prostatectomy. A multivariable Cox regression base model (age, prostate specific antigen, Gleason score/grade group, pathological stage and margin status) was compared with 6 additional models (base model plus each volume related parameter) to evaluate enhancement in predictive accuracy. Decision curve analysis was performed to determine the clinical utility of parameters that enhanced predictive accuracy.

RESULTS

On univariate analysis each parameter was significantly associated with biochemical recurrence except prostate volume. Predictive accuracy of the multivariable base model was high (c-index = 0.861). Adding volume related parameters marginally enhanced discrimination. Decision curve analysis failed to show added benefit even for high grade total tumor volume/total tumor volume, which was the parameter with the highest discriminative improvement.

CONCLUSIONS

Tumor volume related parameters are significantly associated with radical prostatectomy but do not add important discrimination to standard clinicopathological variables for radical prostatectomy prediction or provide benefit across a range of clinically relevant decision thresholds. Volume related measurement is not warranted in routine pathological evaluation and reporting.

Tumor volume improves the long-term prediction of biochemical recurrence-free survival after radical prostatectomy for localized prostate cancer with positive surgical margins

PURPOSE

To develop a novel application evaluating the effect of tumor volume (TV) and percentage of high-grade tumor volume (%HGTV) on long-term biochemical recurrence-free survival rate (BCRFS) after radical prostatectomy (RP) in patients with pT2 PCa.

METHODS

Retrospective analysis of 903 men with pT2 PCa between 1992 and 2004 at a single European tertiary care center was performed. Cox regression models identified risk factors for BCR. A nomogram was developed to predict the BCRFS at 5, 10 and 15 years after RP. Decision curve analyses were performed to identify the net increase in cases identified by the full model.

RESULTS

BCR-free survival rates at 5, 10 and 15 years were 94, 90 and 86 %. In Cox regression analyses, TV, %HGTV and positive surgical margin status (SM) were independent predictors of BCR. Predictive accuracies (PA) at 5, 10 and 15 years of the base model (PSA, Gleason score, SM) were 76.8 % (95 % CI 67.9-78.2 %), 70.5 % (95 % CI 64.9-75.0 %) and 68.1 % (95 % CI 60.6-73.5 %). The full model, including TV and %HGTV, achieved 76.9, 72.4 and 70.7 %. These PA differences were statistically significant at 10 and 15 years (p < 0.001).

CONCLUSIONS

TV and %HGTV could potentially serve as valuable measures to stratify patients at high risk of BCR. The use of our nomogram should be considered to counsel patients with pT2 disease and SM and to design appropriate follow-up or treatment regimens.

Matrix-metalloproteinases in head and neck carcinoma-cancer genome atlas analysis and fluorescence imaging in mice

OBJECTIVE

(1) Obtain matrix-metalloproteinase (MMP) expression profiles for head and neck squamous cell carcinoma (HNSCC) specimens from the Cancer Genomic Atlas (TCGA). (2) Demonstrate HNSCC imaging using MMP-cleavable, fluorescently labeled ratiometric activatable cell-penetrating peptide (RACPP).

STUDY DESIGN

Retrospective human cohort study; prospective animal study.

SETTING

Translational research laboratory.

SUBJECTS AND METHODS

Patient clinical data and mRNA expression levels of MMP genes were downloaded from TCGA data portal. RACPP provides complementary ratiometric fluorescent contrast (increased Cy5 and decreased Cy7 intensities) when cleaved by MMP2/9. HNSCC-tumor bearing mice were imaged in vivo after RACPP injection. Histology was evaluated by a pathologist blinded to experimental conditions. Zymography confirmed MMP-2/9 activity in xenografts. RACPP was applied to homogenized human HNSCC specimens, and ratiometric fluorescent signal was measured on a microplate reader for ex vivo analysis.

RESULTS

Expression of multiple MMPs including MMP2/9 is greater in patient HNSCC tumors than matched control tissue. In patients with human papilloma virus positive (HPV+) tumors, higher MMP2 and MMP14 expression correlates with worse 5-year survival. Orthotopic tongue HNSCC xenografts showed excellent ratiometric fluorescent labeling with MMP2/9-cleavable RACPP (sensitivity = 95.4%, specificity = 95.0%). Fluorescence ratios were greater in areas of higher tumor burden (P < .03), which is useful for intraoperative margin assessment. Ex vivo, human HNSCC specimens showed greater cleavage of RACPP when compared to control tissue (P = .009).

CONCLUSIONS

Human HNSCC tumors show increased mRNA expression of multiple MMPs including MMP2/9. We used RACPP, a ratiometric fluorescence assay of MMP2/9 activity, to show improved occult tumor identification and margin clearance. Ex vivo assays using RACPP in biopsy specimens may identify patients who will benefit from intraoperative RACPP use.

Percentage of high-grade tumour volume does not meaningfully improve prediction of early biochemical recurrence after radical prostatectomy compared with Gleason score

OBJECTIVE

To examine whether percentage of tumour volume (%TV) and percentage of high-grade tumour volume (%HGTV) help to better identify men at higher risk of early biochemical recurrence (BCR) after radical prostatectomy (RP) for non-metastatic high-risk prostate cancer, as early BCR after RP might be associated with higher risk of metastases and cancer-specific mortality.

PATIENTS AND METHODS

We examined the data of 595 men treated with RP for non-metastatic high-risk prostate cancer between 1992 and 2011 at two European tertiary care centres. Kaplan-Meier analyses were used to graphically depict 2-year BCR-free survival. Multivariable Cox regression models addressed early BCR. We tested whether addition of %TV and %HGTV to a multivariable Cox regression model helps to increase a model's predictive accuracy (PA) for prediction of early BCR.

RESULTS

In all, 32 men (10%) with specimen-confined prostate cancer (pT2-pT3a, negative surgical margin, pN0) and 67 men (24%) with non-specimen-confined prostate cancer had early BCR. After stratification according to %HGTV (%HGTV threshold: ≤33.33 vs >33.33%), the 2-year BCR-free survival rates were respectively 93 vs 60% (log-rank P < 0.001). In multivariable Cox regression models %HGTV emerged as an independent predictor of early BCR (P < 0.001), whereas %TV did not (P > 0.05). However, adding %HGTV (regardless of its coding) to other covariates in multivariable Cox regression analysis did not increase the model's PA in a meaningful fashion compared with the use of the detailed Gleason grading system (6 vs 7a vs 7b vs 8 vs 9-10).

CONCLUSIONS

In a large cohort of patients with high-risk prostate cancer, %HGTV and %TV did not improve prediction of early BCR after RP substantially, although %HGTV was an independent predictor of early BCR. Therefore, sophisticated TV/HGTV measurements do not seem to have additional benefit for early BCR prediction relative to the use of Gleason grading. However, these results need to be confirmed in larger, prospective studies.

High percent tumor volume predicts biochemical recurrence after radical prostatectomy in pathological stage T3a prostate cancer with a negative surgical margin

OBJECTIVES

To evaluate the impact of percent tumor volume and surgical margin status on biochemical recurrence in pT3-T4 prostate cancer.

METHODS

A total of 397 patients who had pT3-T4N0 diseases and did not receive neoadjuvant or adjuvant therapy were included for analysis.

RESULTS

In the entire cohort, prostate-specific antigen (per 1 ng/mL increase; hazard ratio 1.019; P = 0.002), pathological stage (T3b-T4 vs T3a; hazard ratio 2.283; P < 0.001), Gleason score (≥8 vs ≤6; hazard ratio 5.290; P = 0.005), surgical margin status (multiple positive vs negative; hazard ratio 1.839; P = 0.003) and lymphovascular invasion (present vs absent; hazard ratio 1.641; P = 0.008) were independent predictors of recurrence. Percent tumor volume was an independent predictor of recurrence in T3a diseases with negative surgical margins. In analysis using receiver operating characteristic curve, a threshold of 12% showed the best balance of sensitivity and specificity, 66% and 67%, respectively. The 5-year recurrence-free survival rates of pT3a diseases with negative surgical margin were 85.2% for percent tumor volume ≤12% and 57.7% for percent tumor volume >12% (P < 0.001). Patients with pT3a with negative surgical margins and percent tumor volume >12% showed comparable 5-year recurrence-free survival rate compared with those with pT3a with positive surgical margin (57.7% vs 57.6%; P = 0.763).

CONCLUSIONS

Despite having less impact on recurrence than other clinicopathological variables in pT3-T4 prostate cancer, percent tumor volume can further improve recurrence risk stratification in pT3a diseases with negative surgical margins.

Trends in prostatic adenocarcinoma tumor volume by visual estimation in prostatectomy specimens

We retrospectively reviewed 1792 consecutive radical prostatectomies (RP) from 2003 to 2006 at a single institution to establish tumor volume reference values, to determine current trends in visually estimated prostate adenocarcinoma tumor volume, and to characterize cases with no residual cancer on RP. Tumor volumes were recorded and subsequently stratified as very low, 0-1%; low, 1.1-10%; intermediate, 10.1-20%; high, 20.1-50%; and very high, >50%, with incidences of 11.7%, 52.1%, 21.5%, 13.2%, and 1.5%, respectively. The incidence of very low volume tumors increased within the time period (p=0.04). Seminal vesicle involvement was detected in 5.0% of cases and lymph node metastasis occurred in 1.4%. Volume categories statistically correlated with seminal vesicle invasion (p=0) and lymph nodes metastases (p=0). Eleven cases of no residual cancer (0.6%) were identified with a non-statically significant increase during the study (p=0.07). The rising incidence of very low volume tumors should be considered by clinicians when discussing treatment options with patients. A discrete tumor volume should be provided for RP specimens as it may be an important prognostic factor.

The association between tumour density and prostate cancer recurrence following radical prostatectomy

PURPOSE

Tumour density (TD) may be an independent prognostic factor in men with prostate cancer. The purpose of this study was to evaluate the association between prostate cancer TD and recurrence following radical prostatectomy.

MATERIALS AND METHODS

Between 1995 and 2007, 645 patients from The Ottawa Hospital or Memorial Sloan-Kettering Cancer Center who had cancer and prostate volumes measured from radical prostatectomy specimens. Tumour density was defined as the relative tumour to prostate volume (tumour volume/prostate volume) and recurrence was defined as a prostate-specific antigen (PSA) >0.2 ng/mL and rising, or postoperative use of radiation or hormonal therapy. Associations between TD and recurrence are adjusted for preoperative PSA, prostatectomy Gleason sum, tumour stage and margin status.

RESULTS

Median follow-up was 40.8 months. Tumour density was associated with preoperative PSA, Gleason sum, tumour stage and surgical margin status (all p < 0.0001). As a continuous variable, TD predicted recurrence-free survival (adjusted HR 1.34 per 10% increase in TD; p = 0.04). As a categorical variable, the group of patients with a TD of >10% had a 2.7 times greater hazard of recurrence compared to patients with a TD <5% (95%CI 1.41, 5.19; p = 0.003). Despite the independent association between TD and recurrence, the clinical value of TD remains in question as the discriminative performance (area under the curve) of predictive models only improved from 0.865 to 0.876.

CONCLUSIONS

Prostate cancer TD is associated with known prognostic factors and is also independently predictive of recurrence following radical prostatectomy.

Does salvage radiation therapy change the biology of recurrent prostate cancer based on PSA doubling times? Results from the SEARCH database

OBJECTIVE

To investigate whether salvage radiation therapy (SRT) may promote prostate cancer (PCa) transformation to more aggressive phenotypes. To accomplish that, we identified men who underwent SRT after radical prostatectomy for PCa and failed SRT. PSA doubling time (PSADT) was used as a surrogate endpoint for cancer aggressiveness. We compared PSADT calculated before start of SRT and after SRT failure.

METHODS

Of 287 men in the SEARCH database since 1988 who underwent SRT, we detected 78 with SRT failure defined as PSA ≥ 0.2 ng/mL above the post-SRT nadir. Of these, 39 had PSADT available before and after SRT, which was compared using Wilcoxon's paired test with men serving as their own controls. We tested predictors of PSADT change using multivariable logistic regression.

RESULTS

There were no differences in PSADT before and after SRT (10.2 vs 12.6 months; P = .46). However, in some individual cases, large changes were observed. Only seminal vesicle invasion showed a trend towards an association with a shorter post-SRT PSADT relative to the pre-SRT PSADT (P = .13).

CONCLUSION

Overall, the PSADT after and before SRT were statistically identical, suggesting that after SRT failure, PCa does not emerge with more aggressive biological features. Further studies are needed to identify predictors and the clinical relevance of individual PSADT changes noted in our study.

Association between preoperative erectile dysfunction and prostate cancer features--an analysis from the Duke Prostate Center Database

INTRODUCTION

Erectile dysfunction (ED) is related to several co-morbidities including obesity, metabolic syndrome, cigarette smoking, and low testosterone, all of which have been reported to be associated with adverse prostate cancer features.

AIM

To examine whether preoperative ED has a relationship with adverse prostate cancer features in patients who underwent radical prostatectomy (RP).

METHODS

We analyzed data from our institution on 676 patients who underwent RP between 2001 and 2010. Crude and adjusted logistic regression models were used to investigate the association between preoperative ED and several pathological parameters. The log-rank test and multivariate proportional hazards model were conducted to determine the association of preoperative ED with biochemical recurrence (BCR).

MAIN OUTCOME MEASURES

The expanded prostate cancer index composite (EPIC) instrument was used to evaluate preoperative erectile function (EF). Preoperative normal EF was defined as EPIC-SF ≥ 60 points while ED was defined as preoperative EPIC-SF lower than 60 points.

RESULTS

Preoperatively, a total of 343 (50.7%) men had normal EF and 333 (49.3%) men had ED. After adjusting for covariates, preoperative ED was identified a risk factor for positive extracapsular extension (OR 1.57; P = 0.029) and high percentage of tumor involvement (OR 1.56; P = 0.047). In a Kaplan-Meier curve, a trend was identified that patients with ED had higher incidence of BCR than men with normal EF (P = 0.091). Moreover, using a multivariate Cox model, higher preoperative EF was negatively associated with BCR (HR 0.99; P = 0.014).

CONCLUSIONS

These results suggest that the likelihood for adverse pathological outcomes as well as BCR following prostatectomy is higher among men with preoperative ED, though these results require validation in larger datasets. The present study indicates that preoperative ED might be a surrogate for adverse prostate cancer outcomes following RP.

The impact of adjuvant therapy in patients with biochemical recurrence on prostate cancer progression and mortality five years after radical prostatectomy

INTRODUCTION

The clinical significance of biochemical recurrence (BCR) after radical prostatectomy (RP) due to prostate cancer (PCa) is not unambiguous, sometimes being independent from the real progression. BCR is followed by a greater risk of adverse events and almost always results with the necessity for implementation of adjuvant therapy (AT). The aim of the following study was to examine the impact of AT in patients with BCR together with PCa progression and mortality 5-years after RP.

MATERIAL AND METHODS

Two hundred forty-seven patients after RP, who were treated in the period from 1995 to 2009, underwent the retrospective analysis. They were divided into three groups according to the applied AT after prior BCR diagnosis. The first group (n - 39) included patients treated with radiotherapy, along with hormonotherapy. The second group (n - 63) covers patients receiving hormonotherapy only. The third group (n - 145) consists of patients without BCR. Five-year general and disease-specific survival was evaluated and choice prognostic factors were compared.

RESULTS

Five-year overall survival was 74.2% in group I, 88.3% in group II, and 98.7% in group III. Diseasespecific survival was: 76.9%, 90.5%, and 100% (p = 0.001), respectively. BCR was diagnosed in 102 (41.5%) patients; while in another 24 (23.5%) of them progression was diagnosed after the AT was applied.

CONCLUSIONS

The risk of BCR 5-years after RP is greater in patients with high initial concentration of PSA, higher Gleason score, and clinical advancement. Five-year overall and disease-specific survivals are higher among patients after hormonotherapy alone compared to those after both radio- and hormonotherapy.

The prognostic significance of percentage of tumour involvement according to disease risk group in men treated with radical prostatectomy

We investigated the prognostic significance of percentage of tumour involvement (PTI) according to the clinicopathological features of prostate cancer among patients who underwent radical prostatectomy (RP). A retrospective study of 534 patients who underwent RP between September 2003 and March 2008 without any neoadjuvant or adjuvant therapy was performed. The associations of PTI with various clinicopathological features and biochemical recurrence-free survival were examined via uni- and multivariate analyses. The predictive accuracy of the multivariate model was assessed with a receiver operating characteristics-derived area under the curve. PTI was demonstrated to be significantly associated with preoperative prostate-specific antigen (PSA) level (P=0.001), pathological Gleason score (P<0.001), extraprostatic tumour extension (P<0.001), seminal vesicle invasion (P<0.001) and positive surgical margin (P<0.001) in univariate analyses. When patients were stratified into disease risk groups, PTI was an independent predictor of biochemical recurrence-free survival in multivariate analysis only among the low-risk group (P=0.033) but not the intermediate- (P=0.287) or the high-risk groups (P=0.828). The addition of the PTI did not significantly increase the accuracy of the multivariate model devised for the prediction of biochemical recurrence-free survival among both total patients (P=0.459) and the low-risk group (P=0.268), respectively. In conclusion, although PTI appeared to be a more significant prognostic factor among patients with low-risk disease than among those with higher risk diseases, overall, the PTI may not provide additional prognostic information beyond what can already be obtained via established prognostic factors.

Tumor volume, surgical margin, and the risk of biochemical recurrence in men with organ-confined prostate cancer

OBJECTIVES

We proposed to investigate predictors of biochemical recurrence (BCR) in pT2 prostate cancer by identifying the interrelationship between the tumor volume and surgical margin status, and their impact on recurrence.

MATERIALS AND METHODS

Clinical, pathologic, and follow-up data of 404 consecutive patients who were treated with radical prostatectomy alone and were diagnosed as pT2 prostate cancer in our institution were reviewed. Percent tumor volume (PTV) was estimated from the cancer distribution map, and the surgical margin status was reviewed by a single pathologist (JYR). Clinicopathologic variables were analyzed with respect to the risk of BCR.

RESULTS AND LIMITATIONS

Recurrence was observed in 39 (9.7%) patients at a mean of 28.9 (5-47) months. Preoperative PSA, biopsy Gleason score, surgical Gleason score, PTV, and surgical margin status were significantly related to BCR in univariate analysis; in multivariate analysis, PTV (P < 0.001) and surgical Gleason score (P = 0.021) were independent predictors of BCR. PTV was also an independent determinant of positive surgical margin (P = 0.035, HR 1.026, 95% CI 1.002-1.050). By combining the 2 predictors 5-year recurrence-free survivals for PTV ≤ 14.5% and surgical Gleason score ≤ 7, PTV >14.5% or surgical Gleason score > 7, and PTV > 14.5% and surgical Gleason score > 7 were 97.5%, 88.7%, and 44.5%, respectively (log-rank test, P < 0.01). Retrospective study nature, use of PTV instead of actual volume, and intermediate follow-up length are the main limitations of the study.

CONCLUSIONS

In men with pT2 prostate cancer, percent tumor volume and the surgical Gleason score were independently prognostic of BCR and by combining the 2 factors, risk of BCR could be significantly stratified. Tumor volume further determined surgical margin status undermining its prognostic value as an independent variable.

Prostate volume has prognostic value only in pathologic T2 radical prostatectomy specimens

The objective of this study was to evaluate the prognostic roles of the prostate volume, tumor volume, and tumor percentage as a function of the pathologic T stage in radical prostatectomy specimens. This study included 259 patients who underwent radical prostatectomy between 2005 and 2010. The mean follow-up period was 41.2 months. In all of the specimens, prostate volume (P = 0.021), the Gleason score (P = 0.035), and seminal vesicle invasion (P = 0.012) were independent predictors of biochemical recurrence (BCR). In the T2 group, multivariate analysis showed that the BCR was significantly associated with prostate specific antigen (PSA) (P = 0.028), a lower prostate volume (P = 0.004), and the Gleason score (P = 0.040). The Kaplan-Meier survival curve showed that a smaller prostate volume was significantly associated with a greater risk of BCR (< 30 vs ≥ 30 mL; P = 0.010). In the T3 group, patients with seminal vesicle invasion had a significantly shorter mean BCR-free survival (P = 0.030). In this study, tumor volume and tumor percentage did not predict BCR. Notably, a lower prostate volume is an independent predictor for BCR only in the organ-confined radical prostatectomy specimens. But, prostate volume could not predict BCR in most locally advanced tumors.

Pathological T2 sub-divisions as a prognostic factor in the biochemical recurrence of prostate cancer

OBJECTIVE

To determine the adequacy of T2 prostate cancer (PCa) sub-staging as an independent Predictor of biochemical disease-free survival (bDFS) after radical prostatectomy.

MATERIALS AND METHODS

The Duke Prostate Center database was queried for patients who underwent radical prostatectomy between 1988 and 2007 and had pT2 PCa, identifying 1990 cases. Prostate-specific antigen (PSA) recurrence was defined as a single value ≥0.2 ng/mL. Kaplan-Meier curves compared differences in bDFS between T2 sub-divisions. Multivariate analysis was performed, adjusting for age, pathological Gleason sum, surgical margin status, preoperative PSA, race, total tumour percentage and prostate weight on biochemical recurrence.

RESULTS

The mean age at surgery was 62 years, and 16% of patients were African-American. Median prostate weight was 40 g [interquartile range (IQR) 31-52] and median preoperative PSA was 5.6 (IQR 4.2-7.8). Pathological Gleason score was ≤6 in 57%, 7 in 38%, and ≥8 in 5%; pathological T stage distribution was 18% T2a, 6% T2b, and 76% T2c; and percentage tumour involvement was ≤5% in 43%, between 5.1 and 10% in 24%, between 10.1 and 15% in 10%, and >15% in 19%. 366 (18.4%) patients had a biochemical recurrence after a median of 4.6 years (IQR 2.1-8.2) follow-up. bDFS was significantly (P= 0.006) higher for pT2a disease than for pT2b and pT2c, which were comparable. Adjusting for demographic and other pathological variables, T2 sub-divisions lost statistical significance.

CONCLUSIONS

Pathological T2a prostate cancer has significantly higher bDFS than the pT2b or pT2c sub-groups in univariate but not multivariate analyses. Different pathological features should be explored to create more meaningfully predictive pathological T2 sub-divisions.

Tumor volume as a predictor of adverse pathologic features and biochemical recurrence (BCR) in radical prostatectomy specimens: a tale of two methods

PURPOSE

The prognostic value of tumor volume in predicting biochemical recurrence after prostatectomy has been debated. Our aim in this study was to (a) evaluate tumor volume as an independent predictor of adverse pathologic outcomes and BCR and (b) determine the effect of two different methods of tumor volume estimation.

METHODS

We reviewed the charts of 3,087 patients who underwent radical prostatectomy at Vanderbilt University Medical Center between 2000 and 2008; of which 1,747 patients had data sufficient for analysis. Prostate specimens were processed as whole mount between 2000 and 2003 and then via systematic sampling from 2003 to 2008, with tumor volume measured by planimetry in the whole-mount group and tumor volume estimated by percent tumor involvement in the systematic sampling group.

RESULTS

Tumor volume estimates were higher with SS than with WM. There were significant associations between larger tumor volume and adverse pathological outcomes, regardless of pathologic method (all with P<0.001). Controlling for other pathologic parameters, tumor volume was an independent predictor of PGS, EPE, and SM in logistic regression models (P<0.001 for TV in all models). Tumor volume was demonstrated to be an independent predictor of BCR in the WM group (1.06, 95% CI 1.01-1.11, P=0.013), though tumor volume was not a significant predictor of BCR in the SS group.

CONCLUSIONS

Though the prognostic value of tumor volume is debated, our data demonstrate that tumor volume, when calculated via planimetry on whole-mount pathologic sectioning, is a significant predictor of biochemical recurrence after prostatectomy.

Screening, risk assessment, and the approach to therapy in patients with prostate cancer

The major challenge in prostate cancer is to identify patients at higher risk of death and to distinguish them from those more likely to die from other causes. Stratification of patients into risk groups can be used to guide management decisions at each disease stage. This review discusses the measures, tools, and nomograms available for risk assessment in prostate cancer. For patients with localized hormone-sensitive disease, the choice is between active surveillance and radical treatment, with focal therapy an emerging option. Current guidelines recommend treatment of patients with a life expectancy ≥10 years, although active surveillance is being used with increasing frequency for low-risk patients, even with a long life expectancy. A number of risk stratification methods have been devised to assess the risk of biochemical recurrence (BCR) after treatment, with prostate-specific antigen (PSA) level, Gleason score, clinical stage, and tumor mass/volume all shown to be predictive of BCR. Among men with BCR after treatment, PSA doubling time (PSADT) was the best predictor of further progression. Although studies in patients with castration-resistant prostate cancer have shown that PSA level and PSADT are associated with a risk of developing metastatic disease, there is currently no clear surrogate for disease progression or overall survival for this patient group and no standard second- or third-line therapy after progression on first-line chemotherapy. The use of newly developed risk-stratification models and markers of disease progression should assist in the earlier identification of disease progression, allowing the optimal treatment of such patients.

A new formula for prostate cancer lymph node risk

INTRODUCTION

The successful treatment of prostate cancer depends on the accurate estimation of the risk of regional lymph node (LN) involvement. The Roach formula (RF) has been criticized as overestimating LN risk. A modification of the RF has been attempted by other investigators using simplified adjustment ratios: the Nguyen formula (NF).

METHODS AND MATERIALS

The National Cancer Institute Surveillance, Epidemiology, and End Results database was investigated for patients treated in 2004 through 2006 for whom at least 10 LN were examined at radical prostatectomy, cT1c or cT2 disease, and prostate-specific antigen (PSA) <26 ng/ml (N = 2,930). The Yale formula (YF) was derived from half of the sample (n = 1,460), and validated in the other half (n = 1,470).

RESULTS

We identified 2,930 patients. Only 4.6% of patients had LN+, and 72.6% had cT1c disease. Gleason (GS) 8-10 histology was found in 14.4% of patients. The YF for prediction of %LN+ risk is [GS - 5] × [PSA/3 + 1.5 × T], where T = 0, 1, and 2 for cT1c, cT2a, and cT2b/cT2c. Within each strata of predicted %LN+ risk, the actual %LN+ was closest to the YF. Using a >15% risk as an indicator of high-risk disease, the YF had increased sensitivity (39.0% vs. 13.6%) compared with the NF, without a significant reduction in specificity (94.9% vs. 98.8%). The NF was overly restrictive of the high-risk group, with only 2% of patients having a >15% risk of LN+ by that formula.

CONCLUSION

The YF performed better than the RF and NF and was best at differentiating patients at high risk for LN+ disease.

Validation of the partin nomogram for prostate cancer in a national sample

PURPOSE

The Partin tables are a nomogram that is widely used to discriminate prostate cancer pathological stages, given common preoperative clinical characteristics. The nomogram is based on patients undergoing radical prostatectomy at The Johns Hopkins Medical Institutions. We validated the Partin tables in a large, population based sample.

MATERIALS AND METHODS

The National Cancer Institute Surveillance, Epidemiology and End Results database was used to identify patients treated from 2004 to 2005 who underwent radical prostatectomy. The 2007 Partin tables were used to estimate the prevalence of positive lymph nodes, seminal vesicle invasion, extraprostatic extension and organ confined disease in men with prostate cancer in the database using clinical stage, preoperative prostate specific antigen and Gleason score. The discriminative ability of the tables was explored by constructing ROC curves.

RESULTS

We identified 11,185 men who underwent radical prostatectomy for prostate cancer in 2004 to 2005. The Partin tables discriminated well between patient groups at risk for positive lymph nodes and seminal vesicle invasion (AUC 0.77 and 0.74, respectively). The discrimination of extraprostatic extension and organ confined disease was more limited (AUC 0.62 and 0.68, respectively). The AUC for positive lymph nodes was 0.78 in white men, 0.73 in black men and 0.83 in Asian/Pacific Islander men (p = 0.17). The AUC for positive lymph nodes in men 61 years old or younger was 0.80 vs 0.74 in men older than 61 years (p = 0.03).

CONCLUSIONS

The Partin tables showed excellent discrimination for seminal vesicle invasion and positive lymph nodes. Discrimination of extraprostatic extension and organ confined disease was more limited. The Partin tables performed best in young men.

The Role of Tumor Volume on Outcome in Prostate Cancer after Prostatectomy

Objective:

Significant study has been made of the role of tumor volume contributing to outcome in prostate cancer: almost two dozen studies have been published on the subject, without clear results either for or against a relationship.

Methods:

An extensive MEDLINE and PUBMED search yielded fourteen articles involving >10,600 patients describing analyses of institutional prostate cancer experiences including tumor volume after radical prostatectomy (RP). Studies were included if multivariate analysis (MVA) was performed including a variable related to tumor volume. All studies had a common outcome of biochemical disease-free (bNED) survival.

Results:

The more rigorous the MVA performed, the more likely tumor volume was to be independently predictive. When the analysis included only tumor volume and Gleason score, studies agreed on outcome half the time. As more variables were added to the analysis, the degree of concordance increased. The two studies with most complete MVAs concur in a volume effect on outcome in over 1470 patients.

Conclusion:

While no meta-analysis on the subject is possible without knowing particulars of each reported case, tumor volume as a predictive variable is likely to be less important than more frequently analyzed factors such as Gleason score and PSA. However, the studies that most completely address the complex and competing variables impacting bNED survival in prostate cancer are those that describe a relationship of tumor volume on outcome.

Tumor volume, tumor percentage involvement, or prostate volume: which is predictive of prostate-specific antigen recurrence?

OBJECTIVES

To compare the effects of tumor volume (TV), tumor percentage involvement (TPI), and prostate volume (PV) on prostate-specific antigen (PSA) recurrence (PSAR) after radical prostatectomy (RP).

METHODS

A cohort of 3528 patients receiving RP between 1988 and 2008 was retrieved from the Duke Prostate Center. Patients were stratified by TV (< 3, 3-6, > 6 cm(3)), TPI (< 10%, 10%-20%, > 20%), and PV (< 35, 35-45, > 45 cm(3)) and their effects on PSAR evaluated using Kaplan-Meier analysis. Clinicopathologic variables included in univariate analysis were age at surgery, race, year of surgery, PSA, pathologic Gleason score, pathologic tumor stage, margin status, extracapsular extension, and seminal vesicle invasion. The effects of TV, TPI, and PV (as continuous and categorical variables) on PSAR were compared using Cox analysis.

RESULTS

TPI, TV, and PV were predictive of PSAR (P <.05) in Kaplan-Meier analysis. In multivariate analysis as continuous variables, TPI and PV were predictive of PSAR (hazard ratio [HR] = 1.16 and HR = 0.65, P <.05). As categorical variables, TPI > 20% and PV 10-35 cm(3) were predictive of PSAR (HR = 1.45 and OR = 1.25, P <.05). TV was not predictive of PSAR in either analysis. Pathologic Gleason score > or = 7, PSA, positive margins, seminal vesicle invasion, and tumor stage T3/T4 were found to be predictors of PSAR (P <.05).

CONCLUSIONS

TV, TPI, and PV were predictive of PSAR in univariate analysis, but in multivariate analysis, only TPI and PV were predictive of PSAR. TPI and PV should be considered when evaluating, assessing, and counseling patients regarding PSAR risk.

Obese men have higher-grade and larger tumors: an analysis of the duke prostate center database

Obesity is associated with increased risk of positive surgical margins and prostate specific antigen (PSA) recurrence among men undergoing radical prostatectomy. To what degree positive margins contribute to poorer outcome is unclear. Thus, we sought to examine the association between body mass index (BMI) and more objective measures of tumor aggressiveness, tumor grade and size. We carried out a retrospective analysis of 2302 patients treated with radical prostatectomy at the Duke Prostate Center from 1988-2007. Tumor volume was calculated by multiplying prostate weight by percent of specimen involved with cancer. Associations between BMI and tumor volume and high-grade disease (Gleason >or=4+3) independent of pre-operative clinical characteristics of age, race, PSA, clinical stage, biopsy Gleason sum, and year of surgery were assessed using linear and logistic regression, respectively. Mean and median BMI among all subjects was 28.1 and 27.6 kg m(-2), respectively. Increased BMI was significantly associated with younger age (P<0.001), black race (P<0.001), more recent year of surgery (P<0.001), and positive surgical margins (P<0.001). After adjusting for multiple clinical pre-operative characteristics, higher BMI was associated with a greater percent of the prostate involved with cancer (P=0.003), increased tumor volume (P<0.001), and high-grade disease (P=0.007). Men with a BMI >or=35 kg m(2) had nearly 40% larger mean tumor volumes than normal weight men (5.1 versus 3.7 cc), after adjustment for multiple clinical characteristics. In this study, obese men undergoing radical prostatectomy had higher-grade and larger tumors, providing further evidence that obese men undergoing radical prostatectomy have more aggressive prostate cancers.