Clinical utility of the percentage of positive prostate biopsies in defining biochemical outcome after radical prostatectomy for patients with clinically localized prostate cancer

Emerging Role of Nuclear Medicine in Prostate Cancer: Current State and Future Perspectives

Prostate cancer is the most frequent epithelial neoplasia after skin cancer in men starting from 50 years and prostate-specific antigen (PSA) dosage can be used as an early screening tool. Prostate cancer imaging includes several radiological modalities, ranging from ultrasonography, computed tomography (CT), and magnetic resonance to nuclear medicine hybrid techniques such as single-photon emission computed tomography (SPECT)/CT and positron emission tomography (PET)/CT. Innovation in radiopharmaceutical compounds has introduced specific tracers with diagnostic and therapeutic indications, opening the horizons to targeted and very effective clinical care for patients with prostate cancer. The aim of the present review is to illustrate the current knowledge and future perspectives of nuclear medicine, including stand-alone diagnostic techniques and theragnostic approaches, in the clinical management of patients with prostate cancer from initial staging to advanced disease.

Value of PHI and PHID in the detection of intermediate- and high-risk prostate cancer

BACKGROUND AND AIMS

PSA testing practice results in a large number of unnecessary prostate biopsies and the overdiagnosis of clinically insignificant prostate cancer (PCa). The aim of our study was to evaluate the value of PHI and PHID for the detection of PCa.

MATERIALS AND METHODS

We measured tPSA, fPSA and p2PSA in 455 patients scheduled for biopsy, including 243 patients with PCa. D'Amico criteria were used to classify these patients in three groups related to risk of progression. Intermediate- and high-risk PCa were considered as aggressive PCa.

RESULTS

The best area under the curve (AUC) value obtained in the detection of aggressive PCa was achieved for PHI and PHID (0.766 and 0.760, respectively). We found a relationship of the performance of by these tests with the calculated prostate volume or the estimated prostate size by digital rectal exam, obtaining the higher AUC in patients with a small prostate. Thus, the AUC for PHI was 0,843 for patients with small calculated prostate volume and 0,817 for patients with small estimated prostate size.

CONCLUSIONS

Our results underline that PHI and PHID outperforms the efficacy obtained with tPSA and %fPSA. Substantial differences in their value in relation to prostate volume were found.

Comparison between Zumsteg classification and Briganti nomogram for the risk of lymph-node invasion before radical prostatectomy

PURPOSE

To evaluate the performance of the Zumsteg classification to estimate the risk of lymph-node invasion (LNI) compared with the Briganti nomogram (BN) in prostatectomy patients with intermediate-risk prostate cancer (IRPC).

METHODS

We included consecutive patients who had extended pelvic lymph-node dissection associated with radical prostatectomy for IRPC. To be classified favorable intermediate risk (FIR), patients could only have one intermediate-risk factor, fewer than 50% positive biopsies and no primary Gleason score of 4.

RESULTS

On the 387 patients included, 149 (38.5%) and 238 (54.3%) were classified FIR and unfavorable intermediate risk (UIR), respectively, and 212 (54.8%) had a BN inferior to 5%. Thirty-eight patients (9.8%) had LNI: 6 FIR patients (4.0%) versus 32 UIR patients (13.4%) and 14 patients (6.6%) with a BN inferior to 5% versus 24 patients (13.7%) with a BN superior to 5%. Eight patients with a BN inferior to 5%, but classified UIR, had LNI. Sensitivity to detect LNI was higher with the Zumsteg classification than with the BN: 84.2% (CI 95% [68-93]) versus 63.2% (CI 95% [46-78]). Both screening tests were concordant to predict LNI (kappa coefficient of 0.076, p < 0.05 for Zumsteg and Briganti) CONCLUSIONS: Zumsteg classification appeared to be more sensitive and as effective (despite the impossibility to make decision curve analysis) than the BN to estimate the risk of LNI. Regarding the modest number of pN+ patients, further studies are needed to see the interest of proposing ePLND for UIR patients only.

Biochemical outcomes and predictive factors by risk group after permanent iodine-125 seed implantation: Prospective cohort study in 2,316 patients

PURPOSE

To evaluate the biochemical freedom from failure (bFFF) by risk group and treatment modality and the predictive factors of bFFF by risk group in patients with prostate cancer undergoing permanent seed implantation (PI) with or without external beam radiation therapy (EBRT) in a nationwide prospective cohort study (Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 [I-125] Seed Implantation) in Japan during the first 2 years.

METHODS AND MATERIALS

The analyses included 2,316 participants in 42 institutions; bFFF was evaluated using the Phoenix definition and calculated using the Kaplan-Meier method, and the Cox proportional hazards model was used to identify the factors associated with bFFF.

RESULTS

Median followup period was 60.0 months. The 5-year bFFF rates in all patients, 1,028 low-risk patients, 1,114 intermediate-risk patients, and 133 high-risk patients were 93.6%, 94.9%, 92.7%, and 91.1%, respectively. The 5-year bFFF rates in the PI group and EBRT combination therapy group were 93.7% and 93.3%, respectively. In a multivariate analysis, younger age, higher Gleason score (GS), higher percent positive biopsies (%PB), and lower prostate V₁₀₀ (p = 0.0012, 0.0030, 0.0026, and 0.0368) in all patients; younger age, higher pretreatment prostate-specific antigen, and lower prostate V₁₀₀ (p = 0.0002, 0.0048, and 0.0012) in low-risk patients; higher GS, higher %PB, and no hormonal treatment (p = 0.0005, 0.0120, and 0.0022) in intermediate-risk patients; and higher GS and higher %PB (p = 0.0329 and 0.0120) in high-risk patients were significantly associated with bFFF.

CONCLUSIONS

PI with or without EBRT resulted in excellent short-term biochemical outcomes in all risk groups, especially in high-risk patients. Age, pretreatment prostate-specific antigen, and prostate V₁₀₀ in low-risk patients; GS, %PB, and hormonal treatment in intermediate-risk patients; and GS and %PB in high-risk patients were independently affected bFFF.

Survival after radiotherapy vs. radical prostatectomy for unfavorable intermediate-risk prostate cancer

BACKGROUND

The optimal treatment for unfavorable intermediate-risk prostate cancer is unknown. Given the lack of randomized evidence, large comparative studies may be useful in guiding clinical decision-making.

METHODS

We queried the National Cancer Database for patients with unfavorable intermediate-risk prostate cancer, as defined by the National Comprehensive Cancer Network. We compared overall survival between patients treated with radical prostatectomy (RP), external beam radiation therapy (EBRT), brachytherapy, and EBRT plus brachytherapy (EBRT+BT) using Cox proportional hazards models and propensity score matching.

RESULTS

A total of 10,439 patients were analyzed. There was no statistically significant difference in overall survival between RP and EBRT+BT (hazard ratio [HR] = 1.24; 95% confidence interval [CI] 0.58-2.65). RP was associated with higher survival when compared to EBRT (HR = 2.30, 95% CI 1.70-3.20) and brachytherapy (HR = 2.90, 95% CI 1.40-6.20). When accounting for androgen deprivation therapy (ADT), there was no statistically significant difference in survival between RP and brachytherapy with ADT (HR = 3.08; 95% CI 0.62-15.27) or EBRT to a dose of ≥7920 cGy with ADT (HR = 2.6, 95% CI 0.50-13.20).

CONCLUSION

We found no statistically significant difference in survival between RP and EBRT+BT. EBRT and brachytherapy had higher mortality, respectively, compared to RP. When including only radiotherapy patients who received ADT and, in the case of EBRT, a total dose ≥ 7920 cGy, there was no statistically significant difference in survival when comparing RP to EBRT or brachytherapy. These findings should be prospectively studied.

Comparative study between 68 Ga-prostate-specific membrane antigen positron emission tomography and conventional imaging in the initial staging of prostate cancer

INTRODUCTION

The management of prostate cancer has undergone significant advances since the introduction of ⁶⁸ Ga-prostate-specific membrane antigen (⁶⁸ Ga-PSMA) positron emission tomography (PET) scans. Data on the use of ⁶⁸ Ga-PSMA PET scans in the setting of biochemical recurrence is widely available. Data on the use of ⁶⁸ Ga-PSMA PET as an initial staging modality, however, is limited. The aim of this retrospective study was to compare the staging of patients with newly diagnosed prostate cancer between ⁶⁸ Ga-PSMA PET and current conventional imaging modalities. The potential impact of any change in stage will be analysed.

METHODS

Details of all patients who underwent ⁶⁸ Ga-PSMA PET in South Australia between March 2016 and March 2017 were obtained. One hundred and thirty-one patients with newly diagnosed prostate cancer who had ⁶⁸ Ga-PSMA PET prior to consideration of definitive treatment were included in this study. The stage pre-⁶⁸ Ga-PSMA PET (based on conventional imaging) and post-⁶⁸ Ga-PSMA PET was recorded. The stage was classified as A - localised disease, B - presence of regional lymphadenopathy, C - oligometastatic disease (up to three metastases) and D - widespread metastases. Management plans were recorded.

RESULTS

This study showed that the use of ⁶⁸ Ga-PSMA PET resulted in a change of stage in 37 (28%) patients with an upstage in 17 (13%) patients and a downstage in 20 (15%) patients (P < 0.001). ⁶⁸ Ga-PSMA PET excluded oligometastatic disease in 11 (8%) patients who had suspicious oligometastatic disease based on a single conventional imaging modality. These ⁶⁸ Ga-PSMA PET findings impacted on management in at least 24 (18%) patients.

CONCLUSION

The use of ⁶⁸ Ga-PSMA PET scans in initial staging can have a significant impact on staging and management when compared to current conventional imaging modalities.

Emerging biomarkers in the diagnosis of prostate cancer

Prostate cancer (PCa) is the second most common cancer in men worldwide. A large proportion of PCa are latent, never destined to progress or affect the patients’ life. It is of utmost importance to identify which PCa are destined to progress and which would benefit from an early radical treatment. Prostate-specific antigen (PSA) remains the most used test to detect PCa. Its limited specificity and an elevated rate of overdiagnosis are the main problems associated with PSA testing. New PCa biomarkers have been proposed to improve the accuracy of PSA in the management of early PCa. Commercially available biomarkers such as PCA3 score, Prostate Health Index (PHI), and the four-kallikrein panel are used with the purpose of reducing the number of unnecessary biopsies and providing information related to the aggressiveness of the tumor. The relationship with PCa aggressiveness seems to be confirmed by PHI and the four-kallikrein panel, but not by the PCA3 score. In this review, we also summarize new promising biomarkers, such as PSA glycoforms, TMPRSS2:ERG fusion gene, microRNAs, circulating tumor cells, androgen receptor variants, and PTEN gene. All these emerging biomarkers could change the management of early PCa, offering more accurate results than PSA. Nonetheless, large prospective studies comparing these new biomarkers among them are required to know their real value in PCa detection and prognosis.

Exosomal and Non-Exosomal Urinary miRNAs in Prostate Cancer Detection and Prognosis

BACKGROUND

MicroRNAs (miRNAs) are non-coding small RNAs, involved in post-transcriptional regulation of many target genes.

METHODS

Five miRNAs that have been consistently found deregulated in PCa (miR-21, miR-141, miR-214, miR-375, and let-7c) were analyzed in urinary pellets from 60 prostate cancer (PCa) patients and 10 healthy subjects by qRT-PCR. Besides, urinary exosomes were isolated by differential centrifugation and analyzed for those miRNAs.

RESULTS

Significant upregulation of miR-21, miR-141, and miR-375 was found comparing PCa patients with healthy subjects in urinary pellets, while miR-214 was found significantly downregulated. Regarding urinary exosomes, miR-21 and miR-375 were also significantly upregulated in PCa but no differences were found for miR-141. Significant differences were found for let-7c in PCa in urinary exosomes while no differences were observed in urinary pellets. A panel combining miR-21 and miR-375 is suggested as the best combination to distinguish PCa patients and healthy subjects, with an AUC of 0.872. Furthermore, the association of miRNAs with clinicopathological characteristics was investigated. MiR-141 resulted significantly correlated with Gleason score in urinary pellets and let-7c with clinical stage in urinary exosomes. Additionally, miR-21, miR-141, and miR-214 were found significantly deregulated in intermediate/high-risk PCa versus low-risk/healthy subjects in urinary pellets. Significant differences between both groups were found in urinary exosomes for miR-21, miR-375, and let-7c.

CONCLUSIONS

These findings suggest that the analysis of miRNAs-especially miRNA-21 and miR-375- in urine could be useful as biomarkers in PCa. Prostate 77: 573-583, 2017. © 2016 Wiley Periodicals, Inc.

Preoperative Multiparametric Magnetic Resonance Imaging Predicts Biochemical Recurrence in Prostate Cancer after Radical Prostatectomy

Objectives

To evaluate the utility of preoperative multiparametric magnetic resonance imaging (MP-MRI) in predicting biochemical recurrence (BCR) following radical prostatectomy (RP).

Materials/Methods

From March 2007 to January 2015, 421 consecutive patients with prostate cancer (PCa) underwent preoperative MP-MRI and RP. BCR-free survival rates were estimated using the Kaplan-Meier method. Cox proportional hazards models were used to identify clinical and imaging variables predictive of BCR. Logistic regression was performed to generate a nomogram to predict three-year BCR probability.

Results

Of the total cohort, 370 patients met inclusion criteria with 39 (10.5%) patients experiencing BCR. On multivariate analysis, preoperative prostate-specific antigen (PSA) (p = 0.01), biopsy Gleason score (p = 0.0008), MP-MRI suspicion score (p = 0.03), and extracapsular extension on MP-MRI (p = 0.03) were significantly associated with time to BCR. A nomogram integrating these factors to predict BCR at three years after RP demonstrated a c-index of 0.84, outperforming the predictive value of Gleason score and PSA alone (c-index 0.74, p = 0.02).

Conclusion

The addition of MP-MRI to standard clinical factors significantly improves prediction of BCR in a post-prostatectomy PCa cohort. This could serve as a valuable tool to support clinical decision-making in patients with moderate and high-risk cancers.

Beyond D'Amico risk classes for predicting recurrence after external beam radiotherapy for prostate cancer: the Candiolo classifier

Background

The aim of this work is to develop an algorithm to predict recurrence in prostate cancer patients treated with radical radiotherapy, getting up to a prognostic power higher than traditional D’Amico risk classification.

Methods

Two thousand four hundred ninety-three men belonging to the EUREKA-2 retrospective multi-centric database on prostate cancer and treated with external-beam radiotherapy as primary treatment comprised the study population. A Cox regression time to PSA failure analysis was performed in univariate and multivariate settings, evaluating the predictive ability of age, pre-treatment PSA, clinical-radiological staging, Gleason score and percentage of positive cores at biopsy (%PC). The accuracy of this model was checked with bootstrapping statistics. Subgroups for all the variables’ combinations were combined to classify patients into five different “Candiolo” risk-classes for biochemical Progression Free Survival (bPFS); thereafter, they were also applied to clinical PFS (cPFS), systemic PFS (sPFS) and Prostate Cancer Specific Survival (PCSS), and compared to D’Amico risk grouping performances.

Results

The Candiolo classifier splits patients in 5 risk-groups with the following 10-years bPFS, cPFS, sPFS and PCSS: for very-low-risk 90 %, 94 %, 100 % and 100 %; for low-risk 74 %, 88 %, 94 % and 98 %; for intermediate-risk 60 %, 82 %, 91 % and 92 %; for high-risk 43 %, 55 %, 80 % and 89 % and for very-high-risk 14 %, 38 %, 56 % and 70 %. Our classifier outperforms D’Amico risk classes for all the end-points evaluated, with concordance indexes of 71.5 %, 75.5 %, 80 % and 80.5 % versus 63 %, 65.5 %, 69.5 % and 69 %, respectively.

Conclusions

Our classification tool, combining five clinical and easily available parameters, seems to better stratify patients in predicting prostate cancer recurrence after radiotherapy compared to the traditional D’Amico risk classes.

Electronic supplementary material

The online version of this article (doi:10.1186/s13014-016-0599-5) contains supplementary material, which is available to authorized users.

Probability of extraprostatic disease according to the percentage of positive biopsy cores in clinically localized prostate cancer

Objective

Prediction of extraprostatic disease in clinically localized prostate cancer is relevant for treatment planning of the disease. The purpose of this study was to explore the usefulness of the percentage of positive biopsy cores to predict the chance of extraprostatic cancer.

Materials and Methods

We evaluated 1787 patients with localized prostate cancer submitted to radical prostatectomy. The percentage of positive cores in prostate biopsy was correlated with the pathologic outcome of the surgical specimen. In the final analysis, a correlation was made between categorical ranges of positive cores (10% intervals) and the risk of extraprostatic extension and/or bladder neck invasion, seminal vesicles involvement or metastasis to iliac lymph nodes. Student's t test was used for statistical analysis.

Results

For each 10% of positive cores we observed a progressive higher prevalence of extraprostatic disease. The risk of cancer beyond the prostate capsule for <10% positive biopsy cores was 7.4% and it increased to 76.2% at the category 90-100% positive cores. In patients with Gleason grade 4 or 5, the risk of extraprostatic cancer prostate was higher than in those without any component 4 or 5.

Conclusion

The percentage of positive cores in prostate biopsy can predict the risk of cancer outside the prostate. Our study shows that the percentage of positive prostate biopsy fragments helps predict the chance of extraprostatic cancer and may have a relevant role in the patient's management.

Predictive values for extracapsular extension in prostate cancer patients with PSA values below 10 ng/mL

OBJECTIVE

We aimed to determine predictive values of extracapsular extension (ECE) in patients who had undergone radical retropubic prostatectomy (RRP) with prostate-specific antigen (PSA) values below 10 ng/mL.

MATERIAL AND METHODS

We retrospectively scanned data of 167 patients with PSA values below 10 ng/mL who had undergone radical retropubic prostatectomy (RRP) between April 2004 and August 2011 in our clinic. Age, PSA, PSA ratio, PSA density, digital rectal examination (DRE) findings, biopsy total Gleason score, perineural invasion (PNI), and lymphovascular invasion (LVI) were analyzed. Parameters of the groups with or without extracapsular extension in RRP pathology specimens were compared.

RESULTS

The mean age of patients was 66.4±12.3 years. According to histopathological analysis of the specimens of RRP of 167 patients, 45 (26.9%) had extracapsular extension (pT3-4) (Group 1); 122 (73.1%) were confined to the prostate (pT2) (Group 2). The mean PSA level was high in Group 1 (p= 0.114), PSA ratio was higher in Group 2 (p=0.09). PSA density was 0.17 in Group 1 and 0.24 in Group 2 (p=0.03). DRE positivity was 53.3% and 57.1%, respectively (p=0.71). Biopsy total Gleason score was higher in Group 1 than Group 2 with a statistically significant difference (p=0.04). A statistically significant difference was found between the rates of PNI and LVI (28.9% and 1.63%, respectively) (p=0.002). There was no statistically significant difference between both groups as for surgical margin positivity (p=0.18).

CONCLUSION

In PCa patients with PSA values below 10 ng/mL, PSA density, lymphovascular invasion and biopsy Gleason total score were statistically significant in predicting extracapsular invasion. Therefore, these results must be considered in preoperative evaluation.

Greatest Percentage Involved Core Length and Risk of Clinically Significant Prostate-Specific Antigen Failure After Radical Prostatectomy

BACKGROUND

Radical prostatectomy (RP) can cure men with unfavorable intermediate- or high-risk prostate cancer (PC). However, some will experience short prostate-specific antigen (PSA) doubling time (PSADT) failure that requires additional treatment with increased toxicity. The present study investigated whether the greatest percentage of involved biopsy core length (GPC) can preoperatively identify men at risk of short PSADT failure.

PATIENTS AND METHODS

A total of 503 men with biopsy-proven PC underwent RP at an academic institution from January 2005 to December 2008. Men with incomplete pathologic information, those who had received neoadjuvant or adjuvant hormonal therapy or chemotherapy, and those who had undergone adjuvant radiation therapy were excluded. The median follow-up period was 4.89 years (interquartile range, 1.97-5.68 years). A competing risk regression was used to assess whether an increasing GPC value was associated with an increased PSADT at < 10-month failure risk, adjusting for age, percentage of positive biopsy results, and risk group.

RESULTS

Of the 402 men, 34 (8.46%) developed PSA failure, 17 (50.0%) of whom had a PSADT of < 10 months. An increasing GPC value was significantly associated with an increased PSADT of < 10-month failure risk (adjusted hazard ratio, 1.03; 95% confidence interval, 1.01-1.06; P = .015). Men with a GPC > 30% (median) versus ≤ 30% and unfavorable intermediate- or high-risk PC (P = .011), but not low or favorable intermediate-risk PC (P = .57), had a significantly greater incidence of PSADT < 10-month failure estimates (30% vs. 0% at 5 years).

CONCLUSION

Men planning to undergo RP for unfavorable intermediate- or high-risk PC with a GPC of > 30% should be considered for randomized trials evaluating the effect on survival of the neoadjuvant use of treatment that extends survival in those with castrate-resistant metastatic PC.

Cytoreductive prostatectomy: evidence in support of a new surgical paradigm (Review)

Prostate cancer (PCa) remains the second ranked cause of cancer deaths in the United States. The current standard of care for metastatic prostate cancer (mPCa) includes systemic therapies with no option for surgery. In contrast, in other malignancies such as breast and kidney cancer, cyto-reduction plays an integral role in the treatment of metastatic disease. In this framework, there are emerging data that suggest a potential oncologic benefit to cytoreduction in mPCa. The majority of the data are retrospective in nature suggesting that patients with mPCa who had prior radical prostatectomy (RP) had a better survival, as well as improved response to systemic therapy. Similarly, patients who presented with metastatic disease and received definitive local therapy (RP or radiation) had greater survival than patients who received no treatment. In order to confer maximum potential benefit, operating in the setting of mPCa must be technically feasible with acceptable morbidity. It has been demonstrated in many studies that operating on locally advanced disease (T3a/b) does have similar morbidity as lower stage cancer. This may be applicable in the metastatic setting, because although PCa may have metastasized, it may remain locally advanced. On the molecular level there are a number of explanations concerning the potential benefit of cytoreduction. However, these ideas remain speculative with no concrete evidence to date.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Correlation of HOXD3 promoter hypermethylation with clinical and pathologic features in screening prostate biopsies

BACKGROUND

Molecular markers that can discriminate indolent cancers from aggressive ones may improve the management of prostate cancer and minimize unnecessary treatment.Aberrant DNA methylation is a common epigenetic event in cancers and HOXD3 promoter hypermethylation (H3PH) has been found in prostate cancer. Our objective was to evaluate the relationship between H3PH and clinicopathologic features in screening prostate biopsies.

METHODS

Ninety-two patients who underwent a prostate biopsy at our institution between October 2011 and May 2012 were included in this study. The core with the greatest percentage of the highest grade disease was analyzed for H3PH by methylation-specific PCR. Correlational analysis was used to analyze the relationship between H3PH and various clinical parameters. Chi-square analysis was used to compare H3PH status between benign and malignant disease.

RESULTS

Of the 80 biopsies with HOXD3 methylation status assessable, 66 sets were confirmed to have cancer. In the 14 biopsies with benign disease there was minimal H3PH with the mean percentage of methylation reference (PMR) of 0.7%. In contrast, the HOXD3 promoter was hypermethylated in 16.7% of all cancers and in 50% of high risk tumors with an average PMR of 4.3% (P=0.008). H3PH was significantly correlated with age (P=0.013), Gleason score (P=0.031) and the maximum involvement of the biopsy core (P=0.035).

CONCLUSIONS

H3PH is associated with clinicopathologic features. The data indicate that H3PH is more common in older higher risk patients. More research is needed to determine the role of this marker in optimizing management strategies in men with newly diagnosed prostate cancer.

Factors that predict the development of bone metastases due to prostate cancer: Recommendations for follow-up and therapeutic options

CONTEXT

Prostate cancer is a public health problem in Spain and in the Western world. Bone involvement, associated to significant morbidity, is practically constant in the advanced stages of the disease. This work aims to review the prognostic factors used in the usual clinical practice that predict the development of bone metastases and to analyze the follow-up and treatment option in these patient profiles.

ACQUIRING OF EVIDENCE

We performed a review of the literature on the useful factors in the context of therapy with intention to cure. We included the classical clinical values in the diagnosis (PSA, clinical stage, Gleason score on the biopsy) pathological factors (pT stage, margins, bladder invasion, tumor volume, lymph node involvement) and PSA kinetics in their different contexts and the histological and molecular parameters.

SYNTHESIS OF EVIDENCE

The tumor differentiation "Gleason" score and PSA are the most important predictive factors in the prediction of bone metastases in patients with intention to cure. Kinetic factors such as PSA doubling time (TDPSA) < 8 months or PSA > 10 ng/ml in the case of castration-resistant prostate cancer (CPRC), are predictive factors for the development of metastasis. Zoledronic acid and denosumab have demonstrated their effectiveness for the treatment of bone disease in randomized studies.

CONCLUSIONS

There are predictive factors within the usual clinical practice that make it possible to recognize the "patient at risk" to develop bone metastatic disease. The currently available treatments, zoledronic acid or denosumab, can help us in the management of the patient at risk of developing metastasis or metastatic patient, increasing the quality of life and decreasing skeletal events.

Greatest percentage of involved core length and the risk of death from prostate cancer in men with highest Gleason score ≥ 7

INTRODUCTION/BACKGROUND

Men with highest GS ≥ 7 and a differing, lower GS core (ComboGS) have decreased PC-specific mortality (PCSM) risk after RT or RT and androgen deprivation therapy (ADT). Whether the greatest percentage of involved core length (GPC) modulates this risk is unknown.

PATIENTS AND METHODS

Men with GS ≥ 7 PC (n = 333) consecutively treated between December 1989 and July 2000 using RT (n = 268; 80%) or RT and 6 months of ADT (n = 65; 20%) comprised the study cohort. The GPC was calculated using biopsy core and tumor lengths. We used competing risks regression to assess whether increasing GPC was associated with increased PCSM risk in men with or without ComboGS adjusting for risk group, age, and treatment.

RESULTS

After a median follow-up of 5.36 years (interquartile range, 3.22-7.61 years), 92 (28%) men died, 28 (30%) of PC. Increasing GPC was significantly associated with increased risk of PCSM (adjusted hazard ratio, 1.02; 95% confidence interval, 1.01-1.03; P = .005). Men with GPC ≥ 50% versus < 50% had significantly greater PCSM estimates when ComboGS was present (P < .001) versus absent (P = .55). Of the 127 men with ComboGS and GPC < 50%, 83% were treated with RT alone and 2 PC deaths were observed; neither in men with GS 7 and favorable intermediate-risk PC.

CONCLUSION

Men treated with RT for ComboGS, GPC < 50%, GS 7, and favorable intermediate-risk PC have a very low risk of early PCSM. The RTOG 0815 trial will establish whether ADT is necessary to optimize curability in these men.

Age and Racial Differences among PSA-Detected (AJCC Stage T1cN0M0) Prostate Cancer in the U.S.: A Population-Based Study of 70,345 Men

Purpose: Few studies have evaluated the risk profile of prostate-specific antigen (PSA)-detected T1cN0M0 prostate cancer, defined as tumors diagnosed by needle biopsy because of elevated PSA levels without other clinical signs of disease. However, some men with stage T1cN0M0 prostate cancer may have high-risk disease (HRD), thus experiencing inferior outcomes as predicted by a risk group stratification model.

Methods: We identified men diagnosed with stage T1cN0M0 prostate cancer from 2004 to 2008 reported to the surveillance, epidemiology, and end results (SEER) program. Multivariate logistic regression was used to model the probability of intermediate-risk-disease (IRD) (PSA ≥ 10 ng/ml but <20 ng/ml and/or GS 7), and high-risk-disease (HDR) (PSA ≥ 20 ng/ml, and/or GS ≥ 8), relative to low-risk disease (LRD) (PSA < 10 ng/ml and GS ≤ 6), adjusting for age, race, marital status, median household income, and area of residence.

Results: A total of 70,345 men with PSA-detected T1cN0M0 prostate cancer were identified. Of these, 47.6, 35.9, and 16.5% presented with low-, intermediate-, and high-risk disease, respectively. At baseline (50 years of age), risk was higher for black men than for whites for HRD (OR 3.31, 95% CI 2.85–3.84). The ORs for age (per year) for HRD relative to LRD were 1.09 (95% CI 1.09–1.10) for white men, and as 1.06 (95% CI 1.05–1.07) for black men. Further, among a subgroup of men with low PSA (<10 ng/ml) T1cN0M0 prostate cancer, risk was also higher for black man than for white men at baseline (50 years of age) (OR 2.70, 95% CI 2.09–3.48). The ORs for age (per year) for HRD relative to LRD were 1.09 (95% CI 1.09–1.10) for white men, and as 1.06 (95% CI 1.05–1.07) for black men.

Conclusion: A substantial proportion of men with PSA-detected prostate cancer as reported to the SEER program had HRD. Black race and older age were associated with a greater likelihood of HRD.

Brachytherapy in the therapy of prostate cancer - an interesting choice

Brachytherapy is a curative alternative to radical prostatectomy or external beam radiation [i.e. 3D conformal external beam radiation therapy (CRT), intensity-modulated radiation therapy (IMRT)] with comparable long-term survival and biochemical control and the most favorable toxicity. HDR brachytherapy (HDR-BT) in treatment of prostate cancer is most frequently used together with external beam radiation therapy (EBRT) as a boost (increasing the treatment dose precisely to the tumor). In the early stages of the disease (low, sometimes intermediate risk group), HDR-BT is more often used as monotherapy. There are no significant differences in treatment results (overall survival rate – OS, local recurrence rate – LC) between radical prostatectomy, EBRT and HDR-BT. Low-dose-rate brachytherapy (LDR-BT) is a radiation method that has been known for several years in treatment of localized prostate cancer. The LDR-BT is applied as a monotherapy and also used along with EBRT as a boost. It is used as a sole radical treatment modality, but not as a palliative treatment. The use of brachytherapy as monotherapy in treatment of prostate cancer enables many patients to keep their sexual functions in order and causes a lower rate of urinary incontinence. Due to progress in medical and technical knowledge in brachytherapy (“real-time” computer planning systems, new radioisotopes and remote afterloading systems), it has been possible to make treatment time significantly shorter in comparison with other methods. This also enables better protection of healthy organs in the pelvis. The aim of this publication is to describe both brachytherapy methods.

ACR Appropriateness Criteria prostate cancer--pretreatment detection, staging, and surveillance

Prostate cancer is the most common noncutaneous male malignancy in the United States. The use of serum prostate-specific antigen as a screening tool is complicated by a significant fraction of nonlethal cancers diagnosed by biopsy. Ultrasound is used predominately as a biopsy guidance tool. Combined rectal examination, prostate-specific antigen testing, and histology from ultrasound-guided biopsy provide risk stratification for locally advanced and metastatic disease. Imaging in low-risk patients is unlikely to guide management for patients electing up-front treatment. MRI, CT, and bone scans are appropriate in intermediate-risk to high-risk patients to better assess the extent of disease, guide therapy decisions, and predict outcomes. MRI (particularly with an endorectal coil and multiparametric functional imaging) provides the best imaging for cancer detection and staging. There may be a role for prostate MRI in the context of active surveillance for low-risk patients and in cancer detection for undiagnosed clinically suspected cancer after negative biopsy results. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Is a visible (hypoechoic) lesion at biopsy an independent predictor of prostate cancer outcome?

The aim of this study was to evaluate the prognostic implications of the sonographic appearance of prostate cancers. All patients with biopsy-proven prostate cancer between January 2003 and July 2004 (and at least 5 years of follow-up) were selected retrospectively. After exclusions, 101 patients constituted our study population and were divided into isoechoic (or nonvisible) and hypoechoic (or visible) lesion. The clinical outcomes of these two groups were compared. The outcomes for the two groups were significantly different (p < 0.01). For nonvisible lesions, 37 of the 41 patients (90.2%) had no disease relapse and 2 (4.9%) had biochemical failure. For the visible lesions, 37 of the 60 (61.6%) patients were free of recurrence, 7 (11.7%) had systemic metastases and 10 (16.7%) died of complications related to prostate cancer. Our data show that patients with nonvisible prostate cancer had significantly better outcomes than patients with visible lesions during a five-year period of evaluation.

Biochemical control of prostate cancer with iodine-125 brachytherapy alone: experience from a single institution

AIM

Brachytherapy is an adequate option as monotherapy for localised prostate cancer. The objective of this study was to evaluate and compare biochemical failure free survival (BFFS) after low-dose-rate brachytherapy (LDRB) alone for patients with prostate cancer using ASTRO and Phoenix criteria, and detect prognostic factors.

METHODS

Data on 220 patients treated between 1998 and 2002 with LDRB were retrospectively analysed. Neoadjuvant hormone therapy was used in 74 (33.6%) patients.

RESULTS

Median follow-up was 53.5 months (24-116). Five year BFFS was 83.0% and 83.7% using, respectively, the ASTRO and Phoenix criteria. Low -and intermediate- risk patients presented, respectively, 86.7% and 77.8% 5-year BFFS using the ASTRO definition (p=0.069), and 88.5% and 78.6% considering the Phoenix criteria (p=0.016). Bounce was observed in 66 (30%) patients. Multivariate analysis detected PSA at diagnosis <10 ng/ml and less than 50% positive biopsy fragments as favourable prognostic factors, regarding BF using both criteria. For the Phoenix criteria, also Gleason score <7 and low-risk group were identified as independent favourable prognostic factors.

CONCLUSIONS

LDRB alone should be considered mostly for low-risk patients. PSA level was a strong independent prognostic factor. We support the use of the Phoenix criteria for detection of BF in patients submitted to LDRB alone.

Long-term outcome for very high-risk prostate cancer treated primarily with a triple modality approach to include permanent interstitial brachytherapy

PURPOSE

To evaluate outcome in the most unfavorable subset of high-risk prostate cancer patients treated with a combination of supplemental external beam radiation therapy (EBRT) and brachytherapy.

METHODS AND MATERIALS

Very high-risk prostate cancer was defined as follows: any Gleason score 10, Gleason score 8-9 with >50% of the biopsy cores positive for malignancy, Gleason score 8-9 with a prostate-specific antigen (PSA) >20ng/mL, any clinical stage T3, or any PSA >40ng/mL. One hundred thirty-one patients were identified who met the aforementioned criteria. The median followup was 6.6 years. One hundred twenty (91.6%) patients received supplemental EBRT and 100 (76.4%) received androgen deprivation therapy (median duration, 19.5 months; range, 4-36 months). The median postimplant day 0 D(90) (i.e., the minimum percentage of the prescription dose that covers the planning target volume) was 121.9% of prescription dose. Multiple clinical treatment and dosimetric parameters were evaluated for impact on the evaluated survival parameters.

RESULTS

The median pretreatment PSA and Gleason score were 11.0ng/mL and 8. One hundred ten (84%) patients had a Gleason score ≥8. At 9 and 12 years, the cause-specific survival, biochemical progression-free survival, and overall survival were 91.0% and 86.5%, 87.3% and 87.3%, and 70.5% and 60.5%, respectively. The most common cause of death was heart disease (22.2%) with deaths from nonprostate cancer (12.7%) and prostate cancer (8.3%) being less likely.

CONCLUSIONS

Permanent interstitial brachytherapy usually with supplemental EBRT and androgen deprivation therapy results in excellent biochemical control and cause-specific survival in the most unfavorable subset of high-risk prostate cancer patients. Death from diseases of the heart was more than twice as likely as death from prostate cancer.

High-grade prostatic adenocarcinoma present in a single biopsy core is associated with increased extraprostatic extension, seminal vesicle invasion, and positive surgical margins at prostatectomy

OBJECTIVE

To evaluate the pathologic outcome of prostate-specific antigen-screened patients with high-grade (Gleason score ≥ 8) prostate cancer limited to 1 biopsy core, without clinical evidence of disease.

METHODS

Ninety-two patients with only 1 biopsy core with cancer and treated by radical prostatectomy were divided into 4 groups according to the biopsy Gleason score: 3 + 3 = 6 (23 cases), 3 + 4 = 7 (25 cases), 4 + 3 = 7 (20 cases), and ≥ 8 (24 cases).

RESULTS

Cases with Gleason score ≥ 8 showed a significantly higher proportion of extraprostatic extension (50%), positive surgical margins (21%), and seminal vesicle invasion (12%) when compared with the other groups. Patients with Gleason score ≥ 8 in the biopsy had a 25-fold increased in the odds ratio for extraprostatic extension in the prostatectomy. The incidence of extraprostatic extension was higher in those with prostatic cancer involving ≥ 50% of one core (88%) compared with cases involving <50% (32%).

CONCLUSION

In patients with prostate cancer limited to 1 biopsy core, the presence of Gleason score ≥ 8 significantly increased the incidence of extraprostatic extension, positive surgical margins, and seminal vesicle invasion. The odds ratio was substantially higher in patients with ≥ 50% of Gleason ≥ 8 in the biopsy core. These data might be taken into account for proper clinical management of this set of patients.

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.

Low-dose rate brachytherapy for men with localized prostate cancer

BACKGROUND

Localized prostate cancer is a slow growing tumor for many years for the majority of affected men. Low-dose rate brachytherapy (LDR-BT) is short-distance radiotherapy using low-energy radioactive sources. LDR-BT has been recommended for men with low risk localized prostate cancer.

OBJECTIVES

To assess the benefit and harm of LDR-BT compared to radical prostatectomy (RP), external beam radiotherapy (EBRT), and no primary therapy (NPT) in men with localized prostatic cancer.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (from 1950), and EMBASE (from 1980) were searched in June 2010 as well as online trials registers and reference lists of reviews.

SELECTION CRITERIA

Randomized, controlled trials comparing LDR-BT versus RP, EBRT, and NPT in men with clinically localized prostate cancer.

DATA COLLECTION AND ANALYSIS

Data on study methods, participants, treatment regimens, observation period and outcomes were recorded by two reviewers independently.

MAIN RESULTS

We identified only one RCT (N = 200; mean follow up 68 months). This trial compared LDR-BT and RP. The risk of bias was deemed high. Primary outcomes (overall survival, cause-specific mortality, or metastatic-free survival) were not reported. Biochemical recurrence-free survival at 5 years follow up was not significantly different between LDR-BT (78/85 (91.8%)) and RP (81/89 (91.0%)); P = 0.875; relative risk 0.92 (95% CI: 0.35 to 2.42).For severe adverse events reported at 6 months follow up, results favored LDR-BT for urinary incontinence (LDR-BT 0/85 (0.0%) versus RP 16/89 (18.0%); P < 0.001; relative risk 0) and favored RP for urinary irritation (LDR-BT 68/85 (80.0%) versus RP 4/89 (4.5%); P < 0.001; relative risk 17.80, 95% CI 6.79 to 46.66). The occurrence of urinary stricture did not significantly differ between the treatment groups (LDR-BT 2/85 (2.4%) versus RP 6/89 (6.7%); P = 0.221; relative risk 0.35, 95% CI: 0.07 to 1.68). Long-term information was not available.We did not identify significant differences of mean scores between treatment groups for patient-reported outcomes function and bother as well as generic health-related quality of life.

AUTHORS' CONCLUSIONS

Low-dose rate brachytherapy did not reduce biochemical recurrence-free survival versus radical prostatectomy at 5 years. For short-term severe adverse events, low-dose rate brachytherapy was significantly more favorable for urinary incontinence, but radical prostatectomy was significantly more favorable for urinary irritation. Evidence is based on one RCT with high risk of bias.

Risk-stratified survival rates and predictors of biochemical recurrence after radical prostatectomy in a Nara, Japan, cohort study

BACKGROUND

The aim of this study was to evaluate the oncological outcomes in patients who underwent radical prostatectomy in various risk groups.

METHODS

The subjects were 468 patients with clinically localized or locally advanced adenocarcinoma of the prostate (T1-3N0M0) who underwent retropubic radical prostatectomy with/without neoadjuvant and/or adjuvant therapy at Nara Medical University and its affiliated hospitals between January 1997 and December 2006. All patients were stratified by D'Amico risk classification. The independent predictor of biochemical recurrence was determined in each risk group.

RESULTS

Of all 468 patients, 171 patients showed biochemical recurrence during a mean follow-up period of 53 months. The 5-year estimated biochemical recurrence-free survival rates in the low, intermediate, and high-risk groups were 77.3, 71.3, and 46.3%, respectively. The multivariate analysis using Cox's proportional hazard model showed that patient age in the low-risk group, seminal vesicle involvement in the intermediate-risk group, and prostate-specific antigen value at diagnosis, surgical Gleason score, percent positive core, and perineural invasion in the high-risk group were independent predictors of biochemical recurrence.

CONCLUSIONS

The high-risk patients showed a significant higher biochemical recurrence than the low- and intermediate-risk patients. The independent predictor of biochemical recurrence was different in each risk group.

Measurements of cancer extent in a conservatively treated prostate cancer biopsy cohort

The optimal method for measuring cancer extent in prostate biopsy specimens is unknown. Seven hundred forty-four patients diagnosed between 1990 and 1996 with prostate cancer and managed conservatively were identified. The clinical end point was death from prostate cancer. The extent of cancer was measured in terms of number of cancer cores (NCC), percentage of cores with cancer (PCC), total length of cancer (LCC) and percentage length of cancer in the cores (PLC). These were correlated with prostate cancer mortality, in univariate and multivariate analysis including Gleason score and prostate-specific antigen (PSA). All extent of cancer variables were significant predictors of prostate cancer death on univariate analysis: NCC, hazard ration (HR) = 1.15, 95% confidence interval (CI) = 1.04-1.28, P = 0.011; PPC, HR = 1.01, 95% CI = 1.01-1.02, P < 0.0001; LCC, HR = 1.02, 95% CI = 1.01-1.03, P = 0.002; PLC, HR = 1.01, 95% CI = 1.01-1.02, P = 0.0001. In multivariate analysis including Gleason score and baseline PSA, PCC and PLC were both independently significant P = 0.004 and P = 0.012, respectively, and added further information to that provided by PSA and Gleason score, whereas NNC and LCC were no longer significant (P = 0.5 and P = 0.3 respectively). In a final model, including both extent of cancer variables, PCC was the stronger, adding more value than PLC (χ² (1df) = 7.8, P = 0.005, χ² (1df) = 0.5, P = 0.48 respectively). Measurements of disease burden in needle biopsy specimens are significant predictors of prostate-cancer-related death. The percentage of positive cores appeared the strongest predictor and was stronger than percentage length of cancer in the cores.

The impact of core biopsy fragmentation in prostate cancer

OBJECTIVES

Since accurate tumor localization and quantification are essential requisites avoiding prostate cancer overtreatment, we analyzed the impact of core fragmentation and the relation between core biopsy taken and pathological information in regard to cancer extension and aggressiveness (Gleason score).

METHODS

One hundred and ninety-nine men submitted to trans-rectal prostate biopsy by the same urologist between October 2006 and October 2008 were included, and the number of cores obtained by biopsy compared to the number of cores examined by the same pathologist.

RESULTS

Total core number obtained by biopsy was 21.54 (± 3.56) compared to 24.08 (± 4.77) examined by the pathologist, P < 0.01. Dividing prostate gland by areas such as base, mid and apical right and left, all areas showed statistically different core number between biopsy and pathological examination report (P < 0.01). Mean ratio of positive core cancer length was 0.41 (± 0.12) and 0.32 (± 0.8) comparing individual and overall cores analysis, respectively (P < 0.01). The mean Gleason score in the individual and overall cores analysis were 6.6 (6-9) and 6.3 (6-9), respectively, P < 0.01.

CONCLUSIONS

Considering the ongoing trend for earlier diagnosis of increasing numbers of younger men with low-risk prostate cancer, this study is original and demonstrates the possibility of core fragmentation, explaining in part over- and under-staging. One core per container and an overall Gleason score and percentage of adenocarcinoma for each container are encouraged.

[MRI and prostatic cancer: measurements of kinetic perfusion parameters of gadolinium with a computerized-aided diagnostic tool (CAD)]

OBJECTIVES

To assess with a CAD in the peripheral (ZP) and transitional (ZT) zones the areas with modifications of the kinetic parameter Kep (ratio of exchanges between vascular compartment and extravascular extracellular spaces) in prostatic cancers with DCE MRI before radical prostatectomy.

METHODS

Forty-two consecutive patients (mean age 67 years, mean PSA: 8.9 ng/ml) with a prostatic cancer proved after a set of 12 biopsies underwent, before radical prostatectomy, a dynamic MRI (1.5T) with a surface coil after injection of gadolinium. We look with a CAD for foci of voxels with an abnormal Kep in ZP and/or in ZT. Foci of abnormal voxels computerized were compared with histological results of radical prostatectomies: prostates were shared in 12 sectors (six peripheral and six central) and a total of 504 sectors were studied. The links between prostatic capsule and foci of voxels with elevated Kep were systematically evaluated. The location and the local extension of the various cancerous foci were estimated. A comparison with the results of the T2W and T1 DCE MRI sequences without use of the CAD was made.

RESULTS

Eighty-eight percent of investigated patients revealed at least a cancerous focus associated with a group of pathological voxels. Hundred and seventy-eight of the 504 investigated prostatic sectors revealed a cancerous lesion after radical prostatectomy (RP) and 116 a focus of voxels with a pathological Kep being linked to 71 isolated lesions, some of them filling several sectors (47 peripheral and 24 transitional). The automatic research with the software of foci of voxels with a parameter Kep more than 2,2 per minute to detect a cancerous lesion had a sensitivity by sector less than the reading without CAD (69% in ZP and 58% in ZT against respectively, 85 and 66% (p<0.01) but seemed more specific: 98% in PZ and 95% in ZT against respectively, 80 and 82% (p<0.01). After RP, 16 cancers were classified Pt2, 10 Pt2R+ and 16 Pt3. The CAD had a better accuracy (74%) than T2W MRI (60%) to look for an extracapsular extension (EPE) or a risk of positive margins: 86% of extraprostatic extension and 60% of positive margins were near a focus of pathological voxels.

CONCLUSIONS

CAD allowed a computerized qualitative and quantitative study of DCE MRI. It identified and localized with a good specificity the significant foci. A focus of voxels with elevated Kep against the capsule increased significantly the risk of an extraprostatic extension or a positive margin after radical prostatectomy.

Wnt5a signaling is involved in the aggressiveness of prostate cancer and expression of metalloproteinase

Wnt5a is a representative ligand that activates the beta-catenin-independent pathway in Wnt signaling. Although it has been reported that abnormal activation of the Wnt/beta-catenin-dependent pathway is often observed in human prostate cancer, the involvement of the beta-catenin-independent pathway in this cancer is unclear. Abnormal expression of Wnt5a and beta-catenin was observed in 27 (28%) and 49 (50%) of 98 prostate cancer cases, respectively, by immunohistochemical analyses. Simultaneous expression of Wnt5a and beta-catenin was observed in only five cases, suggesting their exclusive expression. The positive detection of Wnt5a was correlated with high Gleason scores and biochemical relapse of prostate cancer, but that of beta-catenin was not. Knockdown and overexpression of Wnt5a in human prostate cancer cell lines reduced and stimulated, respectively, their invasion activities, and the invasion activity required Frizzled2 and Ror2 as Wnt receptors. Wnt5a activated Jun-N-terminal kinase through protein kinase D (PKD) and the inhibition of PKD suppressed Wnt5a-dependent cell migration and invasion. In addition, Wnt5a induced the expression of metalloproteinase-1 through the recruitment of JunD to its promoter region. These results suggest that Wnt5a promotes the aggressiveness of prostate cancer and that its expression is involved in relapse after prostatectomy.