Tumour volume is an independent predictor of prostate-specific antigen recurrence in patients undergoing radical prostatectomy for clinically localized prostate cancer

The role of tumor density in predicting significant cancer on targeted biopsy of the prostate

OBJECTIVE

Multiparametric magnetic resonance imaging (mpMRI) is central to diagnosing prostate cancer; however, not all imaged lesions represent clinically significant tumors. We aimed to evaluate the association between the relative tumor volume on mpMRI and clinically significant prostate cancer on biopsy.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 340 patients who underwent combined transperineal targeted and systematic prostate biopsies between 2017 and 2021. Tumor volume was estimated based on the mpMRI diameter of suspected lesions. Relative tumor volume (tumor density) was calculated by dividing the tumor and prostate volumes. The study outcome was clinically significant cancer on biopsy. Logistic regression analyses were used to evaluate the association between tumor density and the outcome. The cutoff for tumor density was determined with ROC curves.

RESULTS

Median estimated prostate and peripheral zone tumor volumes were 55cm3 and 0.61cm3, respectively. Median PSA density was 0.13 and peripheral zone tumor density was 0.01. Overall, 231 patients (68%) had any cancer and 130 (38%) had clinically significant cancer. On multivariable logistic regression age, PSA, previous biopsy, maximal PI-RADS score, prostate volume, and peripheral zone tumor density were significant predictors of outcome. Using a threshold of 0.006, the sensitivity, specificity, positive and negative predictive values of peripheral zone tumor density were 0.9, 0.51, 0.57, and 0.88, respectively.

CONCLUSION

Peripheral zone tumor density is associated with clinically significant prostate cancer in patients with PI-RADS 4 and 5 mpMRI lesions. Future studies are required to validate our findings and evaluate the role of tumor density in avoiding unnecessary biopsies.

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.

Is tumour volume an independent predictor of outcome after radical prostatectomy for high-risk prostate cancer?

BACKGROUND

Preoperative PSA, ISUP grade group (GG), prostate examination and multiparametric MRI (mpMRI) form the basis of prostate cancer staging. Unlike other solid organ tumours, tumour volume (TV) is not routinely used aside from crude estimates such as maximum cancer core length. The aim of this study is to assess the role of TV as a marker for oncological outcomes in high-risk non-metastatic prostate cancer.

METHODS

A prospectively maintained database of patients undergoing minimally invasive (laparoscopic or robot-assisted laparoscopic) radical prostatectomy at a UK centre between 2007 and 2019 were analysed. A total of 251 patients with NCCN high or very high-risk prostate cancer were identified. Primary outcome measure was time to biochemical recurrence (BCR) and the secondary outcome was time to treatment failure (TTF). TV was measured on the pathological specimen using the stacking method. Multivariable cox regression analysis was used to identify factors predicting BCR and TFF. TV as a predictor of BCR and TFF was further analysed through time-dependent receiver operating characteristic (ROC) curves. Kaplan-Meier survival estimates were used to evaluate TV cut-off scores.

RESULTS

Median follow up was 4.50 years. Four factors were associated with BCR and TFF on multivariable analysis (TV, pathological GG, pathological T stage, positive margin >3 mm). Area under the Curve (AUC) for TV as a predictor of BCR and TTF at 5 years was 0.71 and 0.75, respectively. Including all 4 variables in the model increased AUC to 0.84 and 0.85 for BCR and TFF. A 2.50 cm TV cut off demonstrated a significance difference in time to BCR, p < 0.001.

CONCLUSIONS

Pathological tumour volume is an independent predictor of oncological outcomes in high risk prostate cancer but does not add significant prognostic value when combined with established variables. However, the option of accurate TV measurement on mpMRI raises the possibility of using TV as useful marker for preoperative risk stratification.

Can Tumour Volume Percentage in Radical Prostatectomy Predict Cancer Biochemical Recurrence? Determining a Cut-off Point and Composite Risk Factors Approach

BACKGROUND

Incidence of biochemical recurrence (BCR) after radical prostatectomy is relatively high and overall survival can be poor. Debate exists whether tumour volume predicts BCR and when treatments should be administered. In this study, we aimed to i) assess the impact of tumour volume percentage (TVP) as a predictor for BCR, ii) determine TVP cut-off point for BCR and iii) evaluate single and composite predictors of BCR.

METHODS

From March 2000 to December 2013, 1777 patients underwent laparoscopic radical prostatectomy for localized prostate cancer. None received neoadjuvant or adjuvant therapy. One hundred and forty-six patients experienced BCR (range 3 months-10 years). Using D'Amico classification, 146 matched controls without BCR were compared. Liu cut-point analysis was used to identify TVP with optimal sensitivity and specificity. Single and composite BCR risk predictors were analyzed using Cox hazards regression in cases and controls.

RESULTS

Median TVP was 10% (range 1-90%). Most of BCR peaked after 3 years of follow-up. TVP ≥8% was an independent predictor of BCR with HR 1.6 (p= 0.001, 95% CI= 1.11-2.48). TVP of 8% was associated with the highest accuracy: sensitivity 74% and specificity 53% (ROC curve= 0.7). At TVP ≥8%, pathological stage pT3 was associated with 1.7-fold higher risk of BCR compared to T2. Lymph node invasion was associated with 1.4-fold higher risk of BCR compared to no invasion. Combining TVP ≥8%, pT3 and lymph node invasion, HR jumped to 3.73 (p< 0.001, 95% CI= 2.27-6.14), whereas combining TVP ≥8%, positive surgical margin and lymph node invasion, HR was 2.68 (p= 001, 95% CI= 1.50-4.77).

CONCLUSION

TVP can be used as an independent predictor of BCR after radical prostatectomy for prostate cancer. TVP cut-point of ≥8% allows the best discrimination. TVP should be considered in combination with other clinico-pathological factors to improve prediction of long-term oncological outcomes and to stratify BCR risk.

Applications of Artificial Intelligence to Prostate Multiparametric MRI (mpMRI): Current and Emerging Trends

Prostate carcinoma is one of the most prevalent cancers worldwide. Multiparametric magnetic resonance imaging (mpMRI) is a non-invasive tool that can improve prostate lesion detection, classification, and volume quantification. Machine learning (ML), a branch of artificial intelligence, can rapidly and accurately analyze mpMRI images. ML could provide better standardization and consistency in identifying prostate lesions and enhance prostate carcinoma management. This review summarizes ML applications to prostate mpMRI and focuses on prostate organ segmentation, lesion detection and segmentation, and lesion characterization. A literature search was conducted to find studies that have applied ML methods to prostate mpMRI. To date, prostate organ segmentation and volume approximation have been well executed using various ML techniques. Prostate lesion detection and segmentation are much more challenging tasks for ML and were attempted in several studies. They largely remain unsolved problems due to data scarcity and the limitations of current ML algorithms. By contrast, prostate lesion characterization has been successfully completed in several studies because of better data availability. Overall, ML is well situated to become a tool that enhances radiologists' accuracy and speed.

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.

Consensus statements on the management of clinically localized prostate cancer from the Hong Kong Urological Association and the Hong Kong Society of Uro-Oncology

OBJECTIVE

To formulate consensus statements to facilitate physician management strategies for patients with clinically localized prostate cancer (PCa) in Hong Kong by jointly convening a panel of 12 experts from the two local professional organizations representing PCa specialists, who had previously established consensus statements on the management of metastatic PCa for the locality.

METHODS

Through a series of meetings, the panellists discussed their clinical experience and the published evidence regarding various areas of the management of localized PCa, then drafted consensus statements. At the final meeting, each drafted statement was voted on by every panellist based on its practicability of recommendation in the locality.

RESULTS

A total of 76 consensus statements were ultimately accepted and established by panel voting.

CONCLUSION

Derived from the recent evidence and major overseas guidelines, along with local clinical experience and practicability, the consensus statements were aimed to serve as a practical reference for physicians in Hong Kong for the management of localized PCa.

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.

URG11 promotes proliferation and induced apoptosis of LNCaP cells

von Willebrand factor C and EGF domain-containing protein (URG11), a cell growth regulator, is involved in the progression of a variety of types of cancer, including prostate cancer (Pca). However, the functions of the URG11 gene in Pca cells require in-depth investigation. The mRNA and protein levels of URG11 were measured by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. Cell Counting kit-8 (CCK-8), wound-healing and Transwell assays were used to detect cell viability, migration and invasion, respectively. Apoptosis and cell cycle analyses were performed using flow cytometry. The mRNA and protein expression levels of epithelial (E)-cadherin, vimentin, α-smooth muscle actin (α-SMA), cyclin D1 and MYC proto-oncogene protein (c-Myc) were analyzed by RT-qPCR and western blot analysis. In the present study, the mRNA and protein levels of URG11 were markedly upregulated in Pca cell lines compared with those in the normal prostate epithelial cell line. With functional experiments, the cell viability, migration and invasion of Pca cells were markedly promoted by URG11 overexpression. The cell cycle was effectively induced by URG11 and apoptosis was inhibited by the overexpression of URG11. Concomitantly, the epithelial marker E-cadherin was downregulated, and the mesenchymal markers vimentin and α-SMA were upregulated following URG11 overexpression. By contrast, genetic knockout of URG11 elicited the opposite effects. The present study also identified that the downstream effector genes of the Wnt/β-catenin signal pathway, cyclin D1 and c-Myc, were increased following the overexpression of endogenous URG11, which are known to regulate cell proliferation. In addition, the Wnt/β-catenin inhibitor FH535 ameliorated the promotive effects of URG11 on LNCaP cells viability, migration and invasion, and the Wnt/β-catenin agonist LiCl reversed the inhibitory effects of siURG11 in LNCaP cells on cell viability, migration and invasion. The present study demonstrated that URG11 served an oncogenic role in the development of Pca cells and provided evidence that URG11 has potential as a novel therapeutic target in Pca.

Evaluating the size criterion for PI-RADSv2 category 5 upgrade: is 15 mm the best threshold?

PURPOSE

The purpose of the study was to determine if the ≥ 15 mm threshold currently used to define PIRADS 5 lesions is the optimal size threshold for predicting high likelihood of clinically significant (CS) cancers.

MATERIALS

Three hundred and fifty-eight lesions that may be changed from category 4 to 5 or vice versa on the basis of the size criterion (category 4: n = 288, category 5: n = 70) from 255 patients were evaluated. Kendall's tau-b statistic accounting for inter-lesion correlation, generalized estimation equation logistic regression, and receiver operating curve analysis evaluated two lesion size-metrics (lesion diameter and relative lesion diameter-defined as lesion diameter/prostate volume) for ability to identify CS (Gleason grade ≥ 3 + 4) cancer at targeted biopsy. Optimal cut-points were identified using the Youden index. Analyses were performed for the whole prostate (WP) and zone-specific sub-cohorts of lesions in the peripheral and transition zones (PZ and TZ).

RESULTS

Lesion diameter showed a modest correlation with Gleason grade (WP: τB = 0.21, p < 0.0001; PZ: τB = 0.13, p = 0.02; TZ: τB = 0.32, p = 0.001), and association with CS cancer detection (WP: AUC = 0.63, PZ: AUC = 0.59, TZ: AUC = 0.74). Empirically derived thresholds (WP: 14 mm, PZ: 13 mm, TZ: 16 mm) performed similarly to the current ≥ 15 mm standard. Lesion relative lesion diameter improved identification of CS cancers compared to lesion diameter alone (WP: τB = 0.30, PZ: τB = 0.24, TZ: τB = 0.42, all p < 0.0001). AUC also improved for WP and PZ lesions (WP: AUC = 0.70, PZ: AUC = 0.68, and TZ: AUC = 0.74).

CONCLUSIONS

The current ≥ 15 mm diameter threshold is a reasonable delineator of PI-RADS category 4 and category 5 lesions in the absence of extraprostatic extension to predict CS cancers. Additionally, relative lesion diameter can improve identification of CS cancers and may serve as another option for distinguishing category 4 and 5 lesions.

Tumor Volume and Clinical Failure in High-Risk Prostate Cancer Patients Treated With Radical Prostatectomy

INTRODUCTION

To identify the most significant cut-off of tumor volume (TV) for prediction of clinical failure (CF) among high-risk prostate cancer (hPCa) patients.

METHODS

Within a multi-institutional cohort, 262 patients treated with radical prostatectomy (RP) for hPCa were identified. CF was defined as local recurrence or distant metastases. A time dependent ROC curve was used to evaluate the area under the curve (AUC) using TV as single marker to predict clinical failure at 10 years. We searched for the TV cut off value with the highest combined sensitivity and specificity predicting CF. Three multivariable Cox regression analyses (MVA) tested the predictors of CF after RP. Predictors of the model 1 were pre-operative PSA, pathologic stage (PT), pathologic Gleason sum (GS), surgical margin status, and lymph node invasion. Predictors of the models 2 and 3 were the same of model 1 plus TV as a continuous or dichotomous variable using the defined cutoff, respectively. Validation (leave-one-out-cross-validation-LOOCV) of each model was performed.

RESULTS

Overall, 46 (17.6%) patients experienced CF. The TV value was 6.29 ml. In MVA of models 2 and 3, PT and GS remained independent predictors of CF. Moreover, in model 2 TV (HR:1.07,) and in model 3 TV >6.29 ml (HR:2.99,) were independently associated with CF. In LOOCV, the C-index of models 1-3 were 65.53%, 71.75%, and 70.26%, respectively.

CONCLUSIONS

TV is an independent predictor of CF in hPCa patients. Patients with a TV exceeding the cut-off of 6.29 ml are more likely to develop CF. Prostate 77:3-9, 2017. © 2016 Wiley Periodicals, Inc.

A comparison of clinical parameters at presentation, pathological outcomes and biochemical relapse between NHS and private patients undergoing radical prostatectomy at a single centre in the United Kingdom

Objective:

We studied our hypothesis that patients with private health insurance (PHI) with prostate cancer present with more favourable pathological outcomes.

Patients and methods:

Data were analysed from 554 patients undergoing radical prostatectomy from 2002 to 2010. A total of 328 patients under the NHS and 226 men had PHI. Two groups were compared for age, PSA, Gleason score, number of cores involved, maximum tumour length on biopsy core, socioeconomic status, imaging and pathological outcomes.

Results:

PHI presented at a younger age (63 vs 61, p = 0.008) and lower mean PSA (9.5 vs 8.04, p = 0.0005). Staging MRI showed a significant difference in usage (77% vs 45% p < 0.001). Importantly there was significant difference in the total tumour volume (4 cc vs 8 cc, p = 0.001). There were significantly more wealthy patients being seen privately ( p < 0.0001). However, on the final Cox regression model only grade, stage and insurance status were significant predictors of BCR.

Conclusions:

Patients with PHI were younger, had a lower presenting PSA and were wealthier. There is a significant difference in the social profile seen, but wealth itself is not protective yet health insurance is. Insurance status and not social status represents a factor in predicting final pathological outcomes after RRP.

The Effect of Tumor-Prostate Ratio on Biochemical Recurrence after Radical Prostatectomy

Purpose

Prostate tumor volume calculated after surgery using pathologic tissue has been shown to be an independent risk factor for biochemical recurrence. Nonetheless, prostate size varies among individuals, regardless of the presence or absence of cancer. We assumed to be lower margin positive rate in the surgical operation, when the prostate volume is larger and the tumor lesion is same. Thus, we defined the tumor-prostate ratio in the ratio of tumor volume to prostate volume. In order to compensate the prostate tumor volume, the effect of tumor-prostate ratio on biochemical recurrence was examined.

Materials and Methods

This study included 251 patients who underwent open retropubic radical prostatectomy for prostate cancer in a single hospital. We analyzed the effects of tumor volume and tumor-prostate ratio, as well as the effects of known risk factors for biochemical recurrence, on the duration of disease-free survival.

Results

In the univariate analysis, the risk factors that significantly impacted disease-free survival time were found to be a prostate-specific antigen level ≥10 ng/mL, a tumor volume ≥5 mL, tumor-prostate ratio ≥10%, tumor capsular invasion, lymph node invasion, positive surgical margins, and seminal vesicle invasion. In the multivariate analysis performed to evaluate the risk factors found to be significant in the univariate analysis, positive surgical margins (hazard ratio=3.066) and a tumor density ≥10% (hazard ratio=1.991) were shown to be significant risk factors for biochemical recurrence.

Conclusions

Tumor-prostate ratio, rather than tumor volume, should be regarded as a significant risk factor for biochemical recurrence.

Limitations and Prospects for Diffusion-Weighted MRI of the Prostate

Diffusion-weighted imaging (DWI) is the most effective component of the modern multi-parametric magnetic resonance imaging (mpMRI) scan for prostate pathology. DWI provides the strongest prediction of cancer volume, and the apparent diffusion coefficient (ADC) correlates moderately with Gleason grade. Notwithstanding the demonstrated cancer assessment value of DWI, the standard measurement and signal analysis methods are based on a model of water diffusion dynamics that is well known to be invalid in human tissue. This review describes the biophysical limitations of the DWI component of the current standard mpMRI protocol and the potential for significantly improved cancer assessment performance based on more sophisticated measurement and signal modeling techniques.

Information-based ranking of 10 compartment models of diffusion-weighted signal attenuation in fixed prostate tissue

This study compares the theoretical information content of single- and multi-compartment models of diffusion-weighted signal attenuation in prostate tissue. Diffusion-weighted imaging (DWI) was performed at 9.4 T with multiple diffusion times and an extended range of b values in four whole formalin-fixed prostates. Ten models, including different combinations of isotropic, anisotropic and restricted components, were tested. Models were ranked using the Akaike information criterion. In all four prostates, two-component models, comprising an anisotropic Gaussian component and an isotropic restricted component, ranked highest in the majority of voxels. Single-component models, whether isotropic (apparent diffusion coefficient, ADC) or anisotropic (diffusion tensor imaging, DTI), consistently ranked lower than multi-component models. Model ranking trends were independent of voxel size and maximum b value in the range tested (1.6-16 mm(3) and 3000-10,000 s/mm(2)). This study characterizes the two major water components previously identified by biexponential models and shows that models incorporating both anisotropic and restricted components provide more information-rich descriptions of DWI signals in prostate tissue than single- or multi-component anisotropic models and models that do not account for restricted diffusion.

Magnetic Resonance Imaging/Transrectal Ultrasonography Fusion Prostate Biopsy Significantly Outperforms Systematic 12-Core Biopsy for Prediction of Total Magnetic Resonance Imaging Tumor Volume in Active Surveillance Patients

OBJECTIVE

To correlate the highest percentage core involvement (HPCI) and corresponding tumor length (CTL) on systematic 12-core biopsy (SBx) and targeted magnetic resonance imaging/transrectal ultrasonography (MRI/TRUS) fusion biopsy (TBx), with total MRI prostate cancer (PCa) tumor volume (TV).

PATIENTS AND METHODS

Fifty patients meeting criteria for active surveillance (AS) based on outside SBx, who underwent 3.0T multiparametric prostate MRI (MP-MRI), followed by SBx and TBx during the same session at our institution were examined. PCa TVs were calculated using MP-MRI and then correlated using bivariate analysis with the HPCI and CTL for SBx and TBx.

RESULTS

For TBx, HPCI and CTL showed a positive correlation (R(2)=0.31, P<0.0001 and R(2)=0.37, P<0.0001, respectively) with total MRI PCa TV, whereas for SBx, these parameters showed a poor correlation (R(2)=0.00006, P=0.96 and R(2)=0.0004, P=0.89, respectively). For detection of patients with clinically significant MRI derived tumor burden greater than 500 mm(3), SBx was 25% sensitive, 90.9% specific (falsely elevated because of missed tumors and extremely low sensitivity), and 54% accurate in comparison with TBx, which was 53.6% sensitive, 86.4% specific, and 68% accurate.

CONCLUSIONS

HPCI and CTL on TBx positively correlates with total MRI PCa TV, whereas there was no correlation seen with SBx. TBx is superior to SBx for detecting tumor burden greater than 500 mm(3). When using biopsy positive MRI derived TVs, TBx better reflects overall disease burden, improving risk stratification among candidates for active surveillance.

Cryotherapy in prostate cancer

Review objectives:

Cryotherapy use has increased due to technological advances. A review of the literature was performed to evaluate the efficacy and outcomes of whole gland, salvage and targeted focal cryotherapy in the management of prostate cancer.

Review findings:

Cryotherapy use has increased significantly over the last 10 years with a trend towards focal ablation. Whole gland cryotherapy, salvage cryotherapy and focal cryotherapy biochemical recurrence rates appear to be comparable to other treatment modalities for low risk disease, however biochemical failure remains difficult to compare across studies due to a lack of consensus regarding appropriate end points for evaluation of cryotherapy. Short-term focal cryotherapy outcomes are encouraging. Side effect profiles for cryotherapy have significantly improved with fourth generation systems while salvage cryotherapy continues to carry a slightly higher risk of incontinence than primary whole gland cryotherapy. The incidence of erectile dysfunction after focal cryotherapy is dramatically lower than that for whole gland ablation.

Conclusions:

Cryotherapy continues to have an active role in the primary and salvage treatment of prostate cancer. Targeted focal cryotherapy is a promising treatment with minimal morbidity. Further long-term data is needed to support targeted therapy in addition to direct comparison with other treatment modalities.

Maximum tumor diameter adjusted to the risk profile predicts biochemical recurrence after radical prostatectomy

Currently, no consensus exists on the best method for tumor quantification in prostate cancer (PCA), and its prognostic value remains controversial. We evaluated how a newly defined maximum tumor diameter (MTD) might contribute to the prediction of biochemical recurrence (BCR) in a consecutive series of PCA patients treated with radical prostatectomy (RP). Patients with PCA who underwent RP without neoadjuvant therapy at a single center were included for analysis. MTD was defined as the largest diameter of all identified tumors in all three dimensions (i.e., length, width, or depth) of the prostate ("Basel technique"). Cox regression models addressed the association of MTD with BCR in three risk groups (low risk-prostate-specific antigen (PSA) < 10 ng/ml, pT2, and Gleason score (GS) ≤ 6; intermediate risk-PSA ≥ 10 and <20 ng/ml and/or pT2 and GS = 7; high risk-PSA > 20 ng/ml or pT3 or GS ≥ 8) and whole cohort. Within a median follow-up of 44 months (interquartile range (IQR) 23-66), 48 patients (9.4 %) in the intermediate-risk and high-risk groups experienced BCR. In multivariate Cox regression analysis, PSA, pathological stage (pT stage), GS, positive surgical margins (PSMs), and MTD > 19.5 mm were independent predictors for BCR (p < 0.05). In subgroup analysis, MTD as a nominal variable (<24.5 and >24.5 mm) was the only independent predictor of BCR in the intermediate-risk group (hazard ratio (HR) 9.933, 95 % confidence interval (CI) 2.070-47.665; p < 0.05). MTD is an independent risk factor of BCR in PC patients after RP. The combination of the MTD with other well-known prognostic factors after RP may improve decision-making concerning follow-up intensity or adjuvant treatment.

Prostate cancer risk alleles are associated with prostate cancer volume and prostate size

PURPOSE

Genome-wide association studies have identified an increasing number of single nucleotide polymorphisms associated with prostate cancer risk. Some of these genetic variants are also associated with serum prostate specific antigen levels and lower urinary tract symptoms, raising the question of whether they are truly prostate cancer biomarkers or simply lead to detection bias. Therefore, we determined whether single nucleotide polymorphisms associated with prostate cancer risk are more strongly associated with tumor or prostate volume.

MATERIALS AND METHODS

The genotypes of 38 validated prostate cancer risk single nucleotide polymorphisms were determined in 1,321 white men who underwent radical prostatectomy. Univariate and multivariate analyses were performed to compare the relationship of single nucleotide polymorphism frequency with total prostate and tumor volumes.

RESULTS

On multivariate analysis 2 single nucleotide polymorphisms on chromosome 8q24, rs16901979 (A) and rs6983267 (G), were significantly associated with increased tumor volume (p=0.01 and 0.02, respectively). In contrast, rs17632542 (T) near the PSA gene on 19q13 was associated with significantly lower tumor volume and rs10788160 (A) on 10q26 was associated with significantly larger prostate volume (p=0.02 and 0.01, respectively).

CONCLUSIONS

Analysis of 38 single nucleotide polymorphisms associated with prostate cancer risk revealed a significant association between several on chromosome 8q24 and increased tumor volume but not prostate volume. This suggests that they are bona fide markers of prostate cancer susceptibility and possibly more aggressive disease. Other prostate cancer risk alleles are associated with prostate specific antigen and increased prostate or decreased tumor volume, suggesting detection bias due to their phenotypic influence.

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.

Rationale for and review of neoadjuvant therapy prior to radical prostatectomy for patients with high-risk prostate cancer

Despite state of the art local therapy, a significant portion of men with high-risk prostate cancer develop progressive disease. Neoadjuvant systemic therapy prior to radical prostatectomy (RP) is an approach that can potentially maximize survival outcomes in patients with localized disease. This approach is under investigation with a wide array of agents and provides an opportunity to assess pathologic and biologic activity of novel treatments. The aim of this review is to explore the past and present role of neoadjuvant therapy prior to definitive therapy with RP in patients with high-risk localized or locally advanced disease. The results of neoadjuvant androgen-deprivation therapy (ADT), including use of newer agents such as abiraterone, are promising. Neoadjuvant chemotherapy, primarily with docetaxel, with or without ADT has also demonstrated efficacy in men with high-risk disease. Other novel agents targeting the vascular endothelial growth factor receptor (VEGFR), epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR), clusterin, and the immune system are currently under investigation and have led to variable results in early clinical trials. Despite optimistic data, approval of neoadjuvant therapy prior to RP in patients with high-risk prostate cancer will depend on positive results from well designed phase III trials.

Do positive surgical margins predict biochemical recurrence in all patients without adjuvant therapy after radical prostatectomy?

Purpose

The objective was to study whether positive surgical margins (PSMs) predict biochemical recurrence (BCR) in all patients without adjuvant therapy after radical prostatectomy (RP).

Materials and Methods

We retrospectively reviewed the medical records of patients who underwent RP for prostate cancer at Veterans Health Service Medical Center from 2005 to 2011. BCR was defined by a prostate-specific antigen (PSA) value ≥0.2 ng/mL. The clinicopathological factors of the PSM group were compared with those of the negative surgical margin (NSM) group, and the predictive impact of a PSM for BCR-free survival were evaluated. In addition, we analyzed the prognostic difference for BCR-free survival between solitary and multiple PSMs.

Results

A PSM was noted in 167 patients (45.5%). BCR was reported in 101 men in total (27.5%). The BCR-free survival rate of the PSM group was lower than that of the NSM group (p<0.001). In a multivariate analysis for the total patients, PSM was significantly associated with BCR-free survival (p<0.001). After stratification by pathological T stage, Gleason score (GS), and preoperative PSA value, PSM was significantly predictive for BCR-free survival in men with pT2 and/or GS ≤6 or 7 and/or a PSA value <10 or 10-20 ng/mL (all p<0.05). Multiple PSMs were more predictive of BCR-free survival than was a solitary PSM (p=0.001).

Conclusions

A PSM is a significant predictor of postoperative BCR in patients with pT2 and/or GS ≤7 and/or preoperative PSA <20 ng/mL. Multiple PSMs are considered a stronger prognostic factor for prediction of BCR than is a solitary PSM.

Gleason score 7 adenocarcinoma of the prostate with lymph node metastases: analysis of 184 radical prostatectomy specimens

CONTEXT

Prostate cancer (PC) with lymph node metastases (LN(+)) is relatively rare, whereas it is relatively common in disease with a Gleason score (GS) 8 to 10 and virtually never seen in PC with GS 6 or less. It is most variable in GS 7 PC.

OBJECTIVE

To determine clinicopathologic features associated with GS 7 PC with LN(+) compared with a control group without lymph node metastases (LN(-)).

DESIGN

We analyzed 184 GS 7 radical prostatectomies with LN(+) and the same number of LN(-) Gleason-matched controls. The LN(+) cases were GS 3 + 4 = 7 (n = 64; 34.8%), GS 4 + 3 = 7 (n = 66; 35.9%), GS 3 + 4 = 7 with tertiary 5 (n = 10; 5.4%), and GS 4 + 3 = 7 with tertiary 5 (n = 44; 23.9%).

RESULTS

The LN(+) cases demonstrated higher average values in preoperative prostate-specific antigen (12.2 versus 8.1 ng/mL), percentage of positive biopsy cores (59.1% versus 42.9%), prostate weight (54.4 versus 49.4 g), number of LNs submitted (12.7 versus 9.4), incidence of nonfocal extraprostatic extension (82.6% versus 63.6%), tumor volume (28.9% versus 14.8%), frequency of lymphovascular invasion (78.3% versus 38.6%), intraductal spread of carcinoma (42.4% versus 20.7%), incidence of satellite tumor foci (16.4% versus 4.3%), incidence of pT3b disease (49.5% versus 14.7%), and lymphovascular invasion in the seminal vesicles (52% versus 30%). There were differences in GS 4 patterns and cytology between LN(+) and LN(-) cases, with the former having higher volumes of cribriform and poorly formed patterns, larger nuclei and nucleoli, and more-frequent macronucleoli. All P ≤ .05.

CONCLUSION

Gleason score 7 PC with LN(+) has features highlighting a more-aggressive phenotype. These features can be assessed as prognostic markers in GS 7 disease on biopsy (eg, GS 4 pattern, intraductal spread, cytology) or at radical prostatectomies (all variables), even in men without LN dissection or LN(-) disease.

Tumor volume adds prognostic value in patients with organ-confined prostate cancer

PURPOSE

This study was designed to assess the independent prognostic value of tumor volume (TV) and whether adding TV provides additional prognostic information for predicting biochemical recurrence (BCR) after radical prostatectomy.

METHODS

We reviewed the medical records of 1,129 patients who underwent radical prostatectomy between July 2005 and July 2011. TV was categorized as minimal (≤1.0 ml), moderate (1.1-5.0 ml), or extensive (>5.0 ml). Cox regression analysis was performed to identify independent predictors of BCR. The predictive accuracies of Cox's proportional hazard regression models with and without TV were quantified and compared using time-dependent receiver operating characteristic curve analysis.

RESULTS

Increasing TV was associated with higher prostate specific antigen, pathological Gleason score, and pathologic tumor stage. TV was an independent predictor of BCR in multivariate analysis (p<0.001). When patients were stratified by organ-confined and nonorgan-confined tumor groups, TV remained an independent predictor of BCR in organ-confined tumors (p<0.001). In the nonorgan-confined tumor group, a significant difference was found only between extensive versus minimal TV (p=0.023). The predictive accuracy of the Cox regression model increased significantly by adding TV in organ-confined tumor group (0.748 vs. 0.704, p<0.05) but not in nonorgan-confined group (0.742 vs. 0.734, p>0.05).

CONCLUSIONS

TV was an independent prognostic predictor of BCR in organ-confined prostate cancers and provided additional prognostic information with increased predictive accuracy. In contrast, TV did not increase the predictive accuracy in nonorgan-confined tumor. TV should be considered as a prognosticator in organ-confined tumors.

Magnetic resonance microscopy of prostate tissue: How basic science can inform clinical imaging development

This commentary outlines how magnetic resonance imaging (MRI) microscopy studies of prostate tissue samples and whole organs have shed light on a number of clinical imaging mysteries and may enable more effective development of new clinical imaging methods.

Does the Presence of Hypoechoic Lesions on Transrectal Ultrasound Suggest a Poor Prognosis for Patients With Localized Prostate Cancer?

Purpose

Materials and Methods

Results

Conclusions

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.

Image guidance in the focal treatment of prostate cancer

PURPOSE OF REVIEW

The advent of prostate-specific antigen screening has led to a seven-fold increase in the incidence of prostate cancer without a resultant decrease in mortality rate. This has led to the belief that urologists are overdetecting and overtreating clinically insignificant disease. To maintain the delicate balance between high cancer cure rate and overtreatment, which could potentially lead to unnecessary morbidities, focal therapy has emerged as the reasonable middle ground. In this article, we present the conceptual basis and the challenges of focal therapy, while emphasizing the critical role of imaging in focal treatment of prostate cancer.

RECENT FINDINGS

Multiple phase I trials have demonstrated the feasibility, short-term efficacy, and safety of focal therapy. Fundamental to the success of these trials and the ultimate acceptance of focal therapy is the integral role of imaging in optimal patient selection. Among the different imaging modalities, only ultrasound and multiparametric MRI are intimately involved in the detection, diagnosis, staging, and treatment of prostate cancer. Each modality has its own unique advantages and shortcomings. Recent advances in enhanced ultrasound modalities, functional MRIs, and biopsy platforms have taken focal therapy one step closer to becoming the standard of care.

SUMMARY

Although early results of phase I focal therapy trials are encouraging, long-term oncological outcomes remain to be elucidated. Incorporation of these technological advances into large prospective trials is needed to establish focal therapy as an important asset in the urologist's armamentarium against prostate cancer.

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.

Calculated tumor volume is an independent predictor of biochemical recurrence in patients who underwent retropubic radical prostatectomy

Purpose. The purpose of this study is to investigate whether the clinicopathological biopsy findings can predict the oncological outcome in patients who undergo radical prostatectomy. Materials and Methods. Between January 1997 and March 2006, 255 patients with clinically localized adenocarcinoma of the prostate (clinical T1-3N0M0) who had undergone retropubic radical prostatectomy were enrolled in this study. None of the patients received neoadjuvant or adjuvant therapy. Clinicopathological parameters were assessed to determine a predictive parameter of biochemical recurrence. Results. Of the total 255 patients, 77 showed biochemical recurrence during the follow-up period. The estimated 5-year overall survival, 5-year cause-specific survival, and 5-year biochemical recurrence-free survival rates were 97.7%, 99.5%, and 67.3%, respectively. Multivariate analysis using the Cox proportional hazards model showed that calculated cancer volume was an independent predictor among the preoperative clinicopathological parameters (P < 0.05). SVI and PSM were independent predictors among the postoperative parameters (SVI; P < 0.001, PSM; P = 0.049). Among the significant preoperative and postoperative parameters, calculated cancer volume remained an independent predictive parameter in multivariate analysis (P < 0.01). Conclusions. Tumor volume, as calculated by preoperative parameters, is an independent predictor of biochemical recurrence in patients who had undergone radical prostatectomy.

Findings in 12-core transrectal ultrasound-guided prostate needle biopsy that predict more advanced cancer at prostatectomy: analysis of 388 biopsy-prostatectomy pairs

We analyzed 5 features on 12-core transrectal ultrasound-guided prostate needle biopsy (TRUS) to predict the extent of cancer at radical prostatectomy (RP). In 388 TRUS-RP pairs, number of positive cores (NPC), percentage of each core involved (%PC), perineural invasion (PNI), Gleason score (GS), distribution of positive cores (DPC), and preoperative prostate-specific antigen (PSA) were correlated with extraprostatic extension (EPE), seminal vesicle invasion (SVI), positive surgical margin (R1), positive lymph nodes (N1), and tumor volume. All features predicted EPE and SVI. NPC, GS, %PC, and PNI strongly predicted R1 status. RP tumor volume was directly proportional to the NPC and %PC. PSA alone and with selected biopsy findings correlated with tumor volume, stage, SVI, and N1 (P < .0001). Contiguous DPC was a significant risk for EPE and SVI (P < .0001) compared with isolated positive cores. Findings at 12-core TRUS along with preoperative PSA reliably predict advanced local disease and have practical value as guides to effective planning for surgical resections.

Impact of positive surgical margins on biochemical relapse after radical retropubic prostatectomy (RRP)

INTRODUCTION

RP (radical prostatectomy) technique continues the major treatment option for men with potential cure and life expectancy exceeding 10 years. The aim of the study is to assess the impact of PSM on BR (biochemical relapse), to identify PSM risk factors, to clarify the factors involved in BR in the absence of PSM.

MATERIAL AND METHODS

Consultation of 171 medical-records from patients submitted to RRP (radical retropubic prostatectomy) between January/2000-December/2005. Mean-age: 64 yr. Mean - PSA (positive surgical margin): 11.88 ng/ml. Clinical staging: 67.8% cT1, 32.2% cT2. GS: ≤6 (66.1%), =7 (21.1%), 8-10 (12.3%). PS: pT0 1.2%, pT2 50.3%, pT3a 36.3%, pT3b 12.9%, pT4 0.6%. pathological Gleason score: ≤6 39.2%, =7 40.9%, 8-10 19.3%. RB definition was PSA ≥0.2 ng/ml. Adjusted Odds-Ratios with 95% confidence intervals (CI) were estimated through univariate logistic regression.

RESULTS

There were PSM in 46 specimens, 28 had single PSM and 18 multiple PSM (≥2). BR occurred in 57 patients (33.3%), with an average time after surgery of 23.5 months - 26 patients had PSM and 31 had not. Statistical significant results for BR in variables PSA, PS and PSM. Quadruples if PSM (p <0.0001), triples in single PSM (p = 0.01) and is 6x higher in multiple PSM (p = 0.001). Regarding factors that influence the presence of PSM, only PS ≥pT3a reach statistical significance (p <0.0001). Patients with BR but without PSM (54.38%), variables statistically significant were: initial PSA >10, (p = 0.029) and pathological Gleason score ≥8 with a risk nearly 4x higher than pathological Gleason score ≤6 (p = 0.027).

CONCLUSIONS

Statistical risk analysis concluded that the presence of PSM in RRP is strongly influenced by PS ≥pT3a. The presence of PSM and their number increase significantly the risk of BR compared to other factors. In the absence of PSM, the factors that seem to be crucial and with greater impact on BR are initial PSA>10 and pathological Gleason score ≥8.

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.

Does body mass index "dilute" the predictive property of prostate-specific antigen for tumor volume at radical prostatectomy?

OBJECTIVE

To evaluate the effect of the body mass index (BMI) as it relates to the predictive value of the preoperative prostate-specific antigen (PSA) level regarding the tumor volume at radical prostatectomy. Stage migration with the widespread use of PSA screening is well documented; however, the association between the PSA level and tumor volume is less defined. Additionally, the effect of obesity on the serum PSA level might cause relative hemodilution and account for the decreased predictive ability of the PSA level to determine the tumor volume in the modern era.

METHODS

We identified 14 293 patients who had undergone radical prostatectomy for prostate cancer from 1987 to 2007 and had a documented BMI. Using the clinicopathologic variables, we examined the relationship among the BMI, preoperative PSA level, and tumor volume at radical prostatectomy using multiple linear regression analysis.

RESULTS

An elevated BMI was associated with an increased pathologic Gleason score (P < .0001), increased tumor volume (P < .0001), and increased prostate size (P < .0001). The preoperative PSA level correlated significantly with the tumor volume (P < .0001). No significant correlation was found between the BMI and preoperative PSA level (P = .39). On multivariate analysis, controlling for the BMI, the preoperative PSA level remained a significant predictor of the tumor volume (P < .0001). The interaction between the preoperative PSA level and BMI in the prediction of the tumor volume was not statistically significant (P = .56), suggesting that the BMI does not affect the association between the PSA level and tumor volume.

CONCLUSION

Our results have shown that the predictive ability of the PSA level for tumor volume is not affected by the BMI. There does not appear to be a need to correct the serum PSA level in relation to the BMI when used in preoperative prediction models of the tumor volume.

Prognostic significance of tumor volume in radical prostatectomy and needle biopsy specimens

PURPOSE

This review addresses the controversies that persist relating to the prognosis and reporting of tumor volume in adenocarcinoma of the prostate.

MATERIALS AND METHODS

A search was performed using the MEDLINE database and referenced lists of relevant studies to obtain articles addressing the quantification of cancer on radical prostatectomy and needle biopsy.

RESULTS

In the 2010 TNM classification system T2 tumor at radical prostatectomy is subdivided into pT2a (unilateral tumor occupying less than ½ a lobe), pT2b (unilateral tumor greater than ½ a lobe) and pT2c (bilateral tumor). This pathological substaging of T2 disease fails on several accounts. In most studies pT2b disease almost does not exist. By the time a tumor is so large that it microscopically occupies more than ½ a lobe, in the majority of cases there is bilateral (pT2c) tumor. An even greater flaw of the substaging system for stage pT2 disease is the lack of prognostic significance. In reporting pathologically organ confined cancer, it should be merely noted as pT2 without further subclassification. The data are conflicting as to the independent prognostic significance of objective measurements of tumor volume in radical prostatectomy specimens. The most likely explanation for the discordant results lies in the strong correlation of tumor volume with other prognostic markers such as extraprostatic extension and positive margins. In studies where it is statistically significant on multivariate analysis, it is unlikely that knowing tumor volume improves prediction of prognosis beyond routinely reported parameters to the degree that it would be clinically useful for an individual patient. An alternative is to record tumor volume as minimal, moderate or extensive, which gives some indication to the urologist as to the extent of disease. Not only does providing an objective measurement not add useful prognostic information beyond what is otherwise routinely reported by the pathologist, but many objective measurements done in routine practice will likely not be an accurate indicator of the true tumor volume. There is also a lack of consensus regarding the best method of measuring tumor length when there are multiple foci in a single core separated by benign intervening prostatic stroma. Some pathologists, this author included, consider discontinuous foci of cancer as if it was 1 uninterrupted focus, the rationale being that these discontinuous foci are undoubtedly the same cancer going in and out of the plane of section. Measuring the cancer from where it starts to where it ends on the core gives the minimal length of cancer in the prostate. Others measure each focus individually, and the sum of these measurements is considered the cancer length on the core. Quantifying cancer with an ocular micrometer to record the total length or percent length of cancer is time-consuming, and the data are conflicting whether this is superior to other, simpler methods and whether any potential differences in predictive accuracy would translate into changes in clinical management. It is recommended that at a minimum the number of positive cores be recorded, unless fragmented involved cores preclude evaluation, along with at least 1 other more detailed measurement such as the percent of core involvement or length of cancer.

CONCLUSIONS

Consensus has been reached on some of the issues relating to quantifying tumor volume in prostate cancer, such as the lack of utility of substaging pT2 disease. Other questions such as whether to include or subtract intervening benign prostate tissue on prostate needle cores will require additional studies. Finally, matters such as the need to quantify cancer at radical prostatectomy or which method of quantifying cancer on needle biopsy is superior will likely remain contentious due to the close interrelationship and redundancy of prognostic variables.

Prognostic factors for the development of biochemical recurrence after radical prostatectomy

Prostate cancer is one of the most common cancers in Western countries and is associated with a considerable risk of mortality. Biochemical recurrence following radical prostatectomy is a relatively common finding, affecting approximately 25% of cases. The aim of our paper was to identify factors that can predict the occurrence of biochemical recurrence, so the patient can be properly counselled pre- and postoperatively. Medline review of the literatures was done followed by a group discussion on the chosen publications and their valuable influence. Preoperative serum total PSA and clinical stage, together with prostatectomy Gleason grade, tumour volume, and perineural and vascular invasions, were the most important variables found to influence outcome.

Pathology in prostate research: optimizing the pathological data

Pathology remains the gold standard for the diagnosis and local staging and grading of prostate cancer. However, as in any discipline, there are variations in national standards and protocols leading to possible significant intra-observer variations. This can significantly impact on the data supplied to clinical trials. Diagnostic and grading criteria. Error rates in the diagnosis of prostate cancer have improved but the possibility that diagnostic error may be discovered has to be addressed in any research series. Major changes in Gleason grading have occurred in the past 40 years and this may lead to suboptimal application of grades in research cohorts, falsely raising the prognostic power of new biomarkers. Tumor measurements and staging criteria. Further information that may provide additional prognostic information include various measures of tumor extent and peri-neural invasion in biopsy specimens. Standardization of measures of tumor extent is necessary to give more useful assessments of prognosis. In radical prostatectomy specimens there are a number of other staging measurements which might be applied, including tumor volume, margin status, extra-capsular extension and nodal positivity though many of these variables are interdependent. Conclusion. Appropriate utilization of such pathological material will produce improved cohorts in which it will be possible to test new biomarkers with increased rigor.

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.

Stage-by-stage effects of surgical margin status on biochemical failure after radical prostatectomy in patients with clinically localized prostate cancer

PURPOSE

To evaluate the effects of pathological stage and surgical margin status on biochemical failure rates after radical prostatectomy (RP).

MATERIALS AND METHODS

The records of 205 patients who underwent RP for clinically localized prostate cancer (CaP) were evaluated. Known risk factors for biochemical failure (BF) were analyzed using univariate and multivariate logistic regression analysis. The effects of surgical margin status together with pathological stage on BF were evaluated. p values lower than 0.05 were accepted to be statistically significant.

RESULTS

Pathological stage, positive surgical margin (PSM), seminal vesicle invasion, lymph node involvement, biopsy Gleason score and postoperative Gleason score were the factors associated with BF in univariate analysis. Logistic regression analysis revealed that pT3a patients with PSM had a significant BF rate when compared to pT2 patients with a negative surgical margin (NSM) (OR 7.46, p = 0.002). pT3a patients with a NSM had a similar BF rate to that of pT2 patients with PSM.

CONCLUSIONS

pT2 patients with PSM had a similar biochemical prognosis to that of pT3a patients without PSM, implicating that a PSM may have a negative effect on prognosis similar to that of extracapsular invasion.