Predicting unilateral prostate cancer on routine diagnostic biopsy: sextant vs extended

Recent Advances in Systematic and Targeted Prostate Biopsies

Prostate biopsy is the definitive investigation to diagnose prostate cancer. The ideal procedure would be one that offers fast and efficient results safely as an outpatient procedure. Historically, transrectal ultrasound (TRUS) biopsy is considered the gold standard but transrectal biopsy can under-sample the anterior and apical regions of the prostate and is associated with a risk of prostate biopsy-related sepsis, which may require intensive care admission. Transperineal (TP) biopsy addresses the inefficient sampling of TRUS biopsy but historically has been done under general anaesthetic, which makes it difficult to incorporate into timed diagnostic pathways such as the National Health Service (NHS) 2-week cancer pathway. TRUS biopsy has remained the mainstay of clinical diagnosis because of its simplicity; however, the recent development of simpler local anaesthetic transperineal techniques has transformed outpatient biopsy practice. These techniques practically eliminate prostate biopsy-related sepsis, have a shallow learning curve and offer effective sampling of all areas of the prostate in an outpatient setting. The effectiveness of TP biopsy has been enhanced by the introduction of multiparametric MRI prior to biopsy, the use of PSA density for risk stratification in equivocal cases and combined with more efficient targeted and systematic biopsies techniques, such as the Ginsburg Protocol, has improved the tolerability and diagnostic yield of local anaesthetic TP biopsies, reducing the risk of complications from the oversampling associated with transperineal template mapping biopsies. Areas where the literature remains unclear is the optimum number of cores needed to detect clinically significant disease (CSD) in patients with a definable lesion on MRI, in particular, whether there is a need for systematic biopsy in the face of equivocal MRI findings to ensure no CSD is missed. The Covid-19 pandemic has had a profound impact on prostate cancer referrals and prostate biopsy techniques within the UK; prior to the pandemic 65% of all prostate biopsies were TRUS, since the pandemic the proportions have reversed such that now over 65% of all prostate biopsies in the NHS are transperineal.

Evolution of Focal Therapy in Prostate Cancer: Past, Present, and Future

Organ sparing approaches for the management of localized prostate cancer were developed in part to overcome the morbidity associated with standard, whole gland treatment options. The first description of focal therapy was now over two decades ago and since that time much has changed. The evolution of patient selection, the approach to ablation, and surveillance after focal therapy have mirrored the technologic advancements in the field as well as the improved understanding of the biology of low-grade, low-risk prostate cancer. This review presents the evidence for the basis of focal therapy from the past to the present and future endeavors.

The change in serum Thiol/Disulphide homeostasis after transrectal ultrasound guided prostate biopsy

Objectives

The aim of this prospective clinical study was to investigate variations in a novel oxidative stress marker (thiol/disulphide homeostasis) in men who underwent transrectal ultrasound guided prostate biopsy (TRUSB).

Materials and Methods

A total of 22 men undergoing TRUSB of the prostate were enrolled in the study. Patients with abnormal digital rectal examination and/or total prostate specific antigen (PSA) over 4ng/mL underwent TRUSB with 12 cores. Serum samples were obtained before and just after the procedure to evaluate the possible changes in thiol/disulphide homeostasis. Mean age, total PSA and free PSA, prostate volume and histopathological data were also recorded.

Results

Mean age of the study population was 65.05±8.89 years. Significant decreases in native and total thiol levels were documented after the biopsy procedure. However, serum disulphide levels and disulphide/native thiol, disulphide/total thiol and native/total thiol ratios did not significantly change after TRUSB. No correlation was observed between oxidative parameters and total PSA and free PSA levels, prostate volume and histopathology of the prostate. However, mean patient age was significantly correlated with mean native and total thiol levels.

Conclusion

Significant decreases in serum native and total thiol levels related to the prostate biopsy procedure suggest that TRUSB causes acute oxidative stress in the human body. Since our trial is the first in the current literature to investigate these oxidative stress markers in urology practice, additional studies are warranted.

Patient selection for prostate focal therapy in the era of active surveillance: an International Delphi Consensus Project

BACKGROUND

Whole-gland extirpation or irradiation is considered the gold standard for curative oncological treatment for localized prostate cancer, but is often associated with sexual and urinary impairment that adversely affects quality of life. This has led to increased interest in developing therapies with effective cancer control but less morbidity. We aimed to provide details of physician consensus on patient selection for prostate focal therapy (FT) in the era of contemporary prostate cancer management.

METHODS

We undertook a four-stage Delphi consensus project among a panel of 47 international experts in prostate FT. Data on three main domains (role of biopsy/imaging, disease and patient factors) were collected in three iterative rounds of online questionnaires and feedback. Consensus was defined as agreement in ⩾80% of physicians. Finally, an in-person meeting was attended by a core group of 16 experts to review the data and formulate the consensus statement.

RESULTS

Consensus was obtained in 16 of 18 subdomains. Multiparametric magnetic resonance imaging (mpMRI) is a standard imaging tool for patient selection for FT. In the presence of an mpMRI-suspicious lesion, histological confirmation is necessary prior to FT. In addition, systematic biopsy remains necessary to assess mpMRI-negative areas. However, adequate criteria for systematic biopsy remains indeterminate. FT can be recommended in D'Amico low-/intermediate-risk cancer including Gleason 4+3. Gleason 3+4 cancer, where localized, discrete and of favorable size represents the ideal case for FT. Tumor foci <1.5 ml on mpMRI or <20% of the prostate are suitable for FT, or up to 3 ml or 25% if localized to one hemi-gland. Gleason 3+3 at one core 1mm is acceptable in the untreated area. Preservation of sexual function is an important goal, but lack of erectile function should not exclude a patient from FT.

CONCLUSIONS

This consensus provides a contemporary insight into expert opinion of patient selection for FT of clinically localized prostate cancer.

New advances in focal therapy for early stage prostate cancer

INTRODUCTION

Prostate focal therapy offers men the opportunity to achieve oncological control while preserving sexual and urinary function. The prerequisites for successful focal therapy are to accurately identify, localize and completely ablate the clinically significant cancer(s) within the prostate. We aim to evaluate the evidence for current and upcoming technologies that could shape the future of prostate cancer focal therapy in the next five years. Areas covered: Current literature on advances in patient selection using imaging, biopsy and biomarkers, ablation techniques and adjuvant treatments for focal therapy are summarized. A literature search of major databases was performed using the search terms 'focal therapy', 'focal ablation', 'partial ablation', 'targeted ablation', 'image guided therapy' and 'prostate cancer'. Expert commentary: Advanced radiological tools such as multiparametric magnetic resonance imaging (mpMRI), multiparametric ultrasound (mpUS), prostate-specific-membrane-antigen positron emission tomography (PSMA-PET) represent a revolution in the ability to understand cancer function and biology. Advances in ablative technologies now provide a menu of modalities that can be rationalized based on lesion location, size and perhaps in the near future, pre-determined resistance to therapy. However, these need to be carefully studied to establish their safety and efficacy parameters. Adjuvant strategies to enhance focal ablation are under development.

Clinical performance of transperineal template guided mapping biopsy for therapeutic decision making in low risk prostate cancer

OBJECTIVES

To evaluate the role of Transperineal Template guided Mapping Biopsy (TTMB) in determining the management strategy in patients with low risk prostate cancer (PCa).

METHODS

We retroscpectively evaluated 169 patients who underwent TTMB at our institution from February 2008 to June 2011. Ninety eight of them harbored indolent PCa defined as: Prostate Specific Antigen<10ng/ml, Gleason score 6 or less, clinical stage T2a or less, unilateral disease and a maximum of one third positive cores at first biopsy and<50% of the core involved. TTMB results were analyzed for Gleason score upgrading and upstaging as compared to initial TransRectal UltraSound (TRUS) biopsies and its influence on the change in the treatment decisions.

RESULTS

TTMB detected cancer in 64 (65%) patients. The upgrade, upstage and both were noted in 33% (n=21), 12% (n=8) and 7% (n=5) respectively of the detected cancers. The disease characteristics was similar to initial TRUS in 30 (48%) patients and TTMB was negative in 34 (35%) patients. Prostate volume was significantly smaller in patients with upgrade and/or upstage noted at TTMB (45.4 vs 37.9; P=.03). TTMB results influenced 73.5% of upgraded and/or upstaged patients to receive radical treatment while 81% of the patients with unmodified stage and/or grade continued active surveillance or focal therapy.

CONCLUSIONS

In patients with low risk PCa diagnosed by TRUS, subsequent TTMB demonstrated cancer upgrade and/or upstage in about one-third of the patients and resulted in eventual change in treatment decision.

The influence of prostate volume on cancer detection in the Chinese population

In western populations, prostate volume (PV) has been proven to be one of the strongest predictors of detecting prostate cancer (PCa) in biopsies. We performed this study in a biopsy cohort, to evaluate associations among the prostate volume, prostate-specific antigen (PSA) and PCa detection in the Chinese population. Between the years, 2007–13, 1486 men underwent prostate biopsy at Huashan Hospital, Fudan University, Shanghai, China. The study population was divided into two groups for analysis according to total PSA (tPSA) range (4 ng ml⁻¹ < tPSA ≤20 ng ml⁻¹ and tPSA > 20 ng ml⁻¹). PV, age, tPSA, digital rectal examination (DRE) and transrectal ultrasound (TRUS) results were also included in the analysis. Although the positive biopsy rates decreased in both tPSA range groups, the downtrend was more pronounced in the 4 ng ml⁻¹ < tPSA ≤20 ng ml⁻¹ group; therefore, we focused on 853 men in this group with increasing PV. In multivariate logistic regression analysis, only DRE was found to be associated with PCa in four PV groups (P < 0.05) and tPSA did not show a good predictive ability when PV exceeded 50 ml (P > 0.05). Further, it may suggest that with increasing PV, the cancer detection rate decreased in men with different tPSA, DRE and TRUS nodule statuses (all P values for trends were <0.001). Our study indicates that in tPSA ranging from 4 to 20 ng ml⁻¹, the use of PV ranges of 0–35 ml, 35–50 ml and > 50 ml might be taken into consideration for the biopsy decision-making in the Chinese population.

Combination of clinical characteristics and transrectal ultrasound-guided biopsy to predict lobes without significant cancer: application in patient selection for hemiablative focal therapy

PURPOSE

A major limitation of performing hemiablative focal therapy (FT) for prostate cancer (PCa) is the possibility of accompanying significant cancer in the contralateral side of the prostate that is missed on prostate biopsy. We attempted to verify whether clinical and biopsy-related parameters can be used to predict the absence of significant cancer in the prostate lobe.

METHODS

We assumed that hemiablative FT could be performed in patients with low-risk PCa, with unilateral tumors as assessed by transrectal ultrasound-guided biopsy. We evaluated 214 patients who had undergone radical prostatectomy (RP) and fulfilled the eligibility criteria. Seemingly preserved lobes, defined by the absence of cancer on biopsy, were classified as lobes with no cancer (LNC), lobes with insignificant cancer (LIC), and lobes with significant cancer (LSC) according to RP pathology. Cases with an estimated tumor volume of <0.5 mL, a Gleason score of <7, and organ confinement without Gleason pattern 4 were classified as LIC. Univariate and multivariate logistic regression analyses were performed to identify predictors for LSC. Predictive accuracies of the multivariate models were assessed using receiver operating characteristic curve-derived areas under the curve.

RESULTS

Of 214 evaluated lobes, 45 (21.0%), 62, (29.0%), and 107 (50.0%) were classified as LNC, LIC, and LSC, respectively. Among the clinical and biopsy-related parameters, prostate-specific antigen density and prostate volume were identified as significant predictors for LSC in univariate regression analysis. However, multivariate analysis did not identify an independent predictor. Predictive accuracies of the multivariate models did not exceed 70.4%.

CONCLUSIONS

Conventional parameters have limited value in predicting LSC in patients who are candidates for hemiablative FT.

[Focal therapy and prostate cancer]

The International Task Force on Prostate Cancer defines focal therapy (FT) for prostate cancer (PCa) as the therapy that "selectively ablates known disease and preserves existing functions, with the overall objective of minimizing lifetime morbidity without compromising life expectancy". FT for the treatment of PCa has been called the "male lumpectomy", an analogue to women's breast lumpectomy for the treatment of breast cancer. Radical prostatectomy continues to be the most frequently performed treatment for localized PCa, as anatomic knowledge and several technical advances, i.e. the introduction of robotic assisted surgery, have led to successful oncological outcome and lower rates of post-treatment morbidity. However, a proportion of patients still experiences a no negligible sexual, urinary, and bowel morbidity. Although the rationale of active surveillance for low-risk PCa (PSA <10 ng/mL, Gleason grade 6 or less, and clinical stage T1c-T2a) is sound, only few of newly diagnosed patients elect this approach. Thus, in the recent years the concept of a "subtotal therapy" gained the interest of some urological schools. The aim of this paper is to review the existing literature in order to provide the status of art on FT for PCa. The manuscript will focus on the characteristics of the target population, on the pre-operative evaluation to localise disease, as well as on perioperative, functional, and disease-control following focal therapy.

Can side-specific biopsy findings predict the side of nodal metastasis in clinically localized prostate cancer? Results from a multicenter prospective survey

BACKGROUND

To evaluate the correlation between the side of positive biopsy (Bx) and the risk of lymph-node metastases (LNMs) on each side and to quantify the risk of contralateral LNMs in patients with unilateral positive biopsy.

METHODS

We analyzed the outcomes of 1599 patients with complete data regarding the sides of positive Bx and LN (lymph-node). By dividing each prostate into two separate sides, we assessed the accuracy of the side-specific Bx details in determining the side of positive nodes; the area under the receiver-operating characteristic (ROC) (AUCs) was used. For patients with unilateral positive Bx, we assessed the risk of homolateral and contralateral LNMs according to the number of total Bx taken and the preoperative risk of LN invasion.

RESULTS

Considering the 3198 prostate sides, there was a strict correlation between the side of positive Bx and the side of LNMs. The ratio of positive/total Bx was more informative than the number of positive core. The AUC for ipsilateral LNMs was significantly higher than that for contralateral LNMs (P = 0.039). In the 805 patients with unilateral positive Bx, the percentage of contralateral LNMs was >30% even considering a more meticulous biopsy scheme and increased in the patients at a higher clinical risk for LN invasion.

CONCLUSION

PCa preferentially metastasizes to ipsilateral LNs but >30% of contralateral LNMs are present. A unilateral LN dissection that is limited to the tumor-bearing side of the gland should not be recommended because of the substantial risk of missing contralateral metastases.

The role of focal therapy in the management of localised prostate cancer: a systematic review

CONTEXT

The incidence of localised prostate cancer is increasing worldwide. In light of recent evidence, current, radical, whole-gland treatments for organ-confined disease have being questioned with respect to their side effects, cancer control, and cost. Focal therapy may be an effective alternative strategy.

OBJECTIVE

To systematically review the existing literature on baseline characteristics of the target population; preoperative evaluation to localise disease; and perioperative, functional, and disease control outcomes following focal therapy.

EVIDENCE ACQUISITION

Medline (through PubMed), Embase, Web of Science, and Cochrane Review databases were searched from inception to 31 October 2012. In addition, registered but not yet published trials were retrieved. Studies evaluating tissue-preserving therapies in men with biopsy-proven prostate cancer in the primary or salvage setting were included.

EVIDENCE SYNTHESIS

A total of 2350 cases were treated to date across 30 studies. Most studies were retrospective with variable standards of reporting, although there was an increasing number of prospective registered trials. Focal therapy was mainly delivered to men with low and intermediate disease, although some high-risk cases were treated that had known, unilateral, significant cancer. In most of the cases, biopsy findings were correlated to specific preoperative imaging, such as multiparametric magnetic resonance imaging or Doppler ultrasound to determine eligibility. Follow-up varied between 0 and 11.1 yr. In treatment-naïve prostates, pad-free continence ranged from 95% to 100%, erectile function ranged from 54% to 100%, and absence of clinically significant cancer ranged from 83% to 100%. In focal salvage cases for radiotherapy failure, the same outcomes were achieved in 87.2-100%, 29-40%, and 92% of cases, respectively. Biochemical disease-free survival was reported using a number of definitions that were not validated in the focal-therapy setting.

CONCLUSIONS

Our systematic review highlights that, when focal therapy is delivered with intention to treat, the perioperative, functional, and disease control outcomes are encouraging within a short- to medium-term follow-up. Focal therapy is a strategy by which the overtreatment burden of the current prostate cancer pathway could be reduced, but robust comparative effectiveness studies are now required.

Parameters predicting postoperative unilateral disease in patients with unilateral prostate cancer in diagnostic biopsy: a rationale for selecting hemiablative focal therapy candidates

BACKGROUND

Focal hemiablative therapy for prostate cancer is a new treatment alternative. Unilateral and unifocal disease are its main limitations. The aim of this study was to identify the epidemiological, clinical and pathological parameters that may predict unilateral disease in patients diagnosed with prostate cancer.

METHODS

We performed a retrospective analysis of patients at our institution between January 2005 and January 2011. Only patients with unilateral disease in prostate biopsy were part of the study. The analysis included age, preoperative prostate-specific antigen (PSA) and its density, prostate volume, biopsy first and second Gleason pattern and Gleason summary, number of biopsy cores, percentage of cancer in biopsy material and the presence of high-grade prostatic intraepithelial neoplasia. Their role as potential predictors was evaluated by univariate and multivariate analysis.

RESULTS

A total of 161 patients had unilateral disease after prostate biopsy. A significant correlation was found between prostate volume, PSA density and percentage of cancer in biopsy material and the presence of unilateral disease in the surgical specimen. These are the same factors significant in the univariate analysis. The results of the multivariate analysis demonstrated that PSA density (p = 0.015) and percentage of cancer in biopsy material (p = 0.028) are the most significant predictors.

INTERPRETATION

Our results demonstrate that PSA density and the percentage of cancer in biopsy cores are significant predictors for prostate cancer unilaterality and should be considered for the selection of hemiablative focal therapy candidates.

Focal brachytherapy for selected low-risk prostate cancers: a pilot study

PURPOSE

To evaluate the feasibility and the early toxicity of focal brachytherapy in highly selected localized prostate cancer patients.

METHODS AND MATERIALS

Twenty-one patients underwent a focal brachytherapy between February 2010 and March 2012, representing 3.7% of the cases treated by our group during this period. Patient selection was based on (at least) two series of prostate biopsies and a high-resolution MRI. Only patients with very limited and localized tumors, according to strict criteria, were selected for the procedure. The technique used a real-time procedure with the implantation of free (125)I seeds and dynamic dose calculation. The prescribed dose for the focal volume was 145Gy.

RESULTS

The treated volume corresponded to a mean value of 34% of the total prostatic volume (range, 20-48%). For the focal volume, the mean D90 and V100 was 183.2Gy (range, 176-188Gy) and 99.3% (range, 98.8-100%), respectively. The technique was performed in an hour and a half. When compared with a previous cohort treated by whole-prostate brachytherapy, urinary toxicity (International Prostate Symptom Score) was borderline reduced (p = 0.04) at 6 months only, whereas the recovery of the International Index of Erectile Function 5 was better (p = 0.014). The International Continence Score was nil in almost all cases as well as rectal toxicity.

CONCLUSION

Focal treatment by brachytherapy is easily feasible with little acute toxicity. Further investigation is needed to assess the results in terms of tumor control and long-term toxicity.

Complications and quality of life after template-assisted transperineal prostate biopsy in patients eligible for focal therapy

OBJECTIVE

To assess the complication rates and quality of life in patients eligible for focal therapy who underwent template-assisted transperineal prostate biopsy (TTPB).

MATERIALS AND METHODS

Eighty-seven patients with low-risk prostate cancer (clinical stage T1c-T2a, prostate-specific antigen level ≤10 ng/mL, biopsy Gleason score ≤6), who were candidates for focal therapy, underwent TTPB. The study details are available from http://clinicaltrials.gov (NCT00928603). The primary outcomes were the complication rates, according to the Clavien-Dindo classification, and changes in the quality of life, evaluated using the International Prostate Symptom Score, International Index of Erectile Function, and Functional Assessment of Cancer Therapy-Prostate questionnaires, before and 1 month after TTPB.

RESULTS

The median patient age was 63.9 years (range 46-78), with a median Charlson comorbidity index of 2.2 (range 0-4). No statistically significant differences were observed when comparing the general and/or specific domains of the International Prostate Symptom Score, International Index of Erectile Function, and Functional Assessment of Cancer Therapy-Prostate results before and 1 month after TTPB (P >.05 for all). Using the Clavien-Dindo classification, we observed 37 cases of grade 1 complications, including 5 (6.1%) cases of macrohematuria, 13 (16%) of hemospermia, 11 (13.5%) of perineal hematoma, 3 (3.7%) of perineal hematoma and hemospermia, and 5 (6.1%) of macrohematuria and hemospermia. Three patients (3.7%) developed a grade II complication (ie, acute urinary retention). Prostate cancer was detected in 54 patients (62.1%). Of 57 patients, 16 (29.6%) were upgraded from Gleason score 3+3/atypical small acinar proliferation to Gleason score 7. Of the 54 patients with positive TTPB findings, 18 (25.3%) showed an anatomic correspondence between the results of previous biopsies and TTPB.

CONCLUSION

TTPB did not appear to have a significant effect on the quality of life of candidates for focal therapy, and the Clavien-Dindo complication rate was negligible.

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

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

Discrepancy in prostate cancer localization between biopsy and prostatectomy specimens in patients with unilateral positive biopsy: implications for focal therapy

BACKGROUND

Unilateral ablative strategy success depends on reliable prediction of prostate cancer (PCA) location. We evaluated the discrepancy in PCA localization between unilateral positive biopsy (PBx) and radical prostatectomy (RP).

METHODS

Between 2004 and 2008, 431 patients were diagnosed with unilateral PCA by 12-core PBx; 179 underwent RP and constituted our study cohort. Specimens were reviewed to map tumor outline and determine number of cancer foci, tumor volume, Gleason score (GS), zone of origin, localization, and pathologic stage.

RESULTS

In 50 men, biopsy and prostatectomy findings correlated (unilateral tumor); in 129, PCA was detected in the contralateral side of the prostate. In 52 patients, 54 clinically significant tumors were missed by biopsy. When patients with true unilateral and missed contralateral disease at RP were compared with respect to prognostic parameters no significant differences were detected. Sixty-one of the 88 patients with preoperative low-risk disease had true unilateral (n = 21) or missed insignificant contralateral (n = 40) PCA; 27 had missed significant contralateral PCA at RP. PSA > 4 ng/ml predicted presence of significant bilateral disease in low-risk population (P = 0.004). Twenty-four of 27 patients with significant bilateral cancer had PSA > 4, although 33/61 with unilateral or bilateral insignificant cancer had similar elevated PSA values.

CONCLUSIONS

Twelve-core biopsy is inadequate to identify candidates for organ-sparing therapy. Most men with unilateral positive biopsies have bilateral cancer at prostatectomy. Tumors missed by biopsy were clinically significant in 40% of patients, but no prognostic parameters could predict unilateral disease. Hemi-ablative treatment might fail to eradicate significant lesions in the contralateral side.

Role of transrectal ultrasonography (TRUS) in focal therapy of prostate cancer: report from a Consensus Panel

What's known on the subject? and What does the study add? Focal therapy techniques are emerging in prostate cancer treatment. However, several key questions about patient selection, treatment and monitoring still have to be addressed. The concept of focal therapy is barely discussed in current urological guidelines. In the present manuscript, we report the results of a consensus meeting focused on ultrasonography, the most common used urological imaging method, in relation to focal therapy of prostate cancer. • To establish a consensus on the utility of ultrasonography (US) to select patients for focal therapy. Topics were the current status of US to determine focality of prostate cancer, to monitor and assess outcome of focal therapy and the diagnostic advantages of new US methods. In addition, the biopsy techniques required to identify focal lesions were discussed. • Urological surgeons, radiation oncologists, radiologists, and basic researchers from Europe and North America participated in a consensus meeting on the use of transrectal US (TRUS) in focal therapy of prostate cancer. The consensus process was face-to-face and specific clinical issues were raised and discussed with agreement sought when possible. • TRUS is commonly used and essential for diagnosing men with prostate cancer. It is particularly useful for targeting specific anatomical regions or visible lesions. However, it has several limitations and there is a need for improvement. Newer visualisation techniques, e.g. colour Doppler US, contrast-enhanced US and elastography, are being developed but currently there is no US technique that can accurately characterise a cancer suitable for focal therapy. Systematic biopsy is the only known procedure that allows the identification of prostate cancers suitable for focal therapy. Scarce data exist about the role of US for monitoring patients during or after ablative therapy. • Consensus was reached on all key aspects of the meeting. • US cannot reliably identify focal prostate cancer. New US methods show promising results in identifying prostate cancer focality. • Currently selecting appropriate candidates for focal therapy should be performed using dedicated protocols and biopsy schemes.

Report of a consensus meeting on focal low dose rate brachytherapy for prostate cancer

What's known on the subject? and What does the study add? Whole gland brachytherapy has been used to successfully treat prostate cancer but the protocol for focal therapy has not previously been established. The consensus findings provide guidance on patient selection for focal brachytherapy as well as recommendations for conducting therapy and patient follow-up. Low dose rate prostate brachytherapy is an effective treatment for localized prostate cancer. Recently, it has been considered for use in a focused manner whereby treatment is targeted only to areas of prostate cancer. The objective of focal brachytherapy is to provide effective cancer control for low-risk disease but with reduced genitourinary and rectal side-effects in a cost-effective way. We report on the outputs of a consensus meeting of international experts in brachytherapy and focal therapy convened to consider the feasibility and potential development of focal brachytherapy. A number of factors were considered for focal brachytherapy including optimal patient selection, disease characterization and localization, treatment protocols and outcome measures. The consensus meeting also addressed the design of a clinical trial that would assess the oncological outcomes and side-effect profiles resulting from focal brachytherapy.

High-dose-rate brachytherapy boost to the dominant intra-prostatic tumor region: hemi-irradiation of prostate cancer

BACKGROUND

To assess the feasibility, toxicity, and outcome of prostate hemi-irradiation with a high-dose-rate brachytherapy (HDR-BT) boost for patients presumed to harbor dominant intra-prostatic tumors in a single lobe.

METHODS

After 3D conformal external radiotherapy (3DCRT) to 64-64.4 Gy, 77 patients with non-metastatic locally aggressive prostate cancer have been treated from 2000 to 2004, with HDR-BT using temporary open MRI-guided (192) Ir implants, to escalate the dose in the boost region. Twenty patients (26%) had one lobe involvement (i.e., one sided endorectal MRI, rectal examination, and biopsies) and were boosted to one side of the gland only. A dose of 12, 14, and 16 Gy in two fractions was delivered to 5, 6, and 9 patients, respectively.

RESULTS

After a median follow-up 69 months, no differences in late rectal toxicity were observed between the unilaterally and bilaterally irradiated cohorts. Although, grade 2 late urinary toxicity was worse in the hemi-irradiated group (P = 0.03), severe grade ≥3 late urinary toxicity at 5 years was not different: 10% versus 8.8% in the unilaterally and bilaterally irradiated cohorts, respectively. Grade 4 late urinary toxicity, however, was exclusively observed in patients boosted to both lobes (5/57, 8.8%). Five-year biochemical relapse-free survival was 79.7% versus 70.5% for the unilateral and bilateral boost groups, respectively (P = 0.99).

CONCLUSION

Prostate hemi-irradiation with a HDR-BT boost to the dominant tumor region may be considered when rectal examination, MRI, and biopsies suggest one lobe involvement. Nevertheless, strict dosimetric optimization is needed in order to further reduce the risk of late severe toxicity.

Beyond diagnosis: evolving prostate biopsy in the era of focal therapy

Despite decades of use as the “gold standard” in the detection of prostate cancer, the optimal biopsy regimen is still not universally agreed upon. While important aspects such as the need for laterally placed biopsies and the importance of apical cancer are known, repeated studies have shown significant patients with cancer on subsequent biopsy when the original biopsy was negative and an ongoing suspicion of cancer remained. Attempts to maximise the effectiveness of repeat biopsies have given rise to the alternate approaches of saturation biopsy and the transperineal approach. Recent interest in focal treatment of prostate cancer has further highlighted the need for accurate detection of prostate cancer, and in response, the introduction of transperineal template-guided biopsy. While the saturation biopsy approach and the transperineal template approach increase the detection rate of cancer in men with a previous negative biopsy and appear to have acceptable morbidity, there is a lack of clinical trials evaluating the different biopsy strategies. This paper reviews the evolution of prostatic biopsy and current controversies.

The role of transrectal saturation biopsy in tumour localization: pathological correlation after retropubic radical prostatectomy and implication for focal ablative therapy

OBJECTIVE

• To evaluate the accuracy of an initial 24-core prostate biopsy scheme (PBx24) in predicting unilateral prostate cancer (PCa) in radical prostatectomy (RP) specimens.

PATIENTS AND METHODS

• Between 2005 and 2008, 203 consecutive patients underwent PBx24 followed by RP for PCa. The area under the curve (AUC) was used to evaluate the accuracy of unilateral PCa on PBx24 to predict unilateral PCa in RP specimens. • The positive predictive value (PPV) and negative predictive value (NPV) were also calculated. Moreover, in patients with unilateral PCa on biopsy, univariable and multivariable logistic regression analyses tested the relationship between the presence of unilateral PCa in an RP specimen and the variables: age, prostate-specific antigen (PSA), total prostate volume, clinical stage, primary Gleason grade, secondary Gleason grade and the number of positive cores.

RESULTS

• PCa cores were unilateral in 115 patients (56.7%) on biopsy. Of those, only 26 (22.6%) had unilateral PCa in the RP specimen (AUC, 72.9%; PPV, 22.6%; NPV, 98.8%). In patients with clinically low-risk tumours, only 17 of 63 (27%) had a unilateral PCa on PBx24 and in the RP specimen (AUC, 59.1%; PPV, 27.0%; NPV, 100.0%). • None of the examined variables was an independent predictor of the presence of unilateral PCa in the RP specimen (all P > 0.05).

CONCLUSIONS

• Initial PBx24 is not sufficiently accurate to be dependable as a method of predicting tumour laterality in RP specimens. Therefore, the use of PBx24 to guide hemi-ablation therapy of PCa may lead to mistreatment in a considerable proportion of patients. • Moreover, none of the routinely available clinical and pathological characteristics appears to improve the ability of unilateral PCa on biopsy to predict unilateral PCa in the RP specimen.

Focal therapy for prostate cancer: possibilities and limitations

CONTEXT

A significant proportion of patients diagnosed with prostate cancer have well-differentiated, low-volume tumors at minimal risk of impacting their quality of life or longevity. The selection of a treatment strategy, among the multitude of options, has enormous implications for individuals and health care systems.

OBJECTIVE

Our aim was to review the rationale, patient selection criteria, diagnostic imaging, biopsy schemes, and treatment modalities available for the focal therapy of localized prostate cancer. We gave particular emphasis to the conceptual possibilities and limitations.

EVIDENCE ACQUISITION

A National Center for Biotechnology Information PubMed search (www.pubmed.gov) was performed from 1995 to 2009 using medical subject headings "focal therapy" or "ablative" and "prostate cancer." Additional articles were extracted based on recommendations from an expert panel of authors.

EVIDENCE SYNTHESIS

Focal therapy of the prostate in patients with low-risk cancer characteristics is a proposed treatment approach in development that aims to eradicate all known foci of cancer while minimizing damage to adjacent structures necessary for the preservation of urinary, sexual, and bowel function. Conceptually, focal therapy has the potential to minimize treatment-related toxicity without compromising cancer-specific outcome. Limitations include the inability to stage or grade the cancer(s) accurately, suboptimal imaging capabilities, uncertainty regarding the natural history of untreated cancer foci, challenges with posttreatment monitoring, and the lack of quality-of-life data compared with alternative treatment strategies. Early clinical experiences with modest follow-up evaluating a variety of modalities are encouraging but hampered by study design limitations and small sample sizes.

CONCLUSIONS

Prostate focal therapy is a promising and emerging treatment strategy for men with a low risk of cancer progression or metastasis. Evaluation in formal prospective clinical trials is essential before this new strategy is accepted in clinical practice. Adequate trials must include appropriate end points, whether absence of cancer on biopsy or reduction in progression of cancer, along with assessments of safety and longitudinal alterations in quality of life.

Recent advances in focal therapy of prostate and kidney cancer

The concept of focal therapy in oncologic surgery refers to maximizing healthy tissue preservation while maintaining excellent cancer control outcomes. Herein, we address the recent advantages in the field of focal therapy for both kidney and prostate cancer, focusing on technological achievements and future perspectives.