Surgical management of prostate cancer: Advances based on a rational approach to the data

High-intensity focused ultrasound with visually directed power adjustment for focal treatment of localized prostate cancer: systematic review and meta-analysis

PURPOSE

To characterize patient outcomes following visually directed high-intensity focused ultrasound (HIFU) for focal treatment of localized prostate cancer.

METHODS

We performed a systematic review of cancer-control outcomes and complication rates among men with localized prostate cancer treated with visually directed focal HIFU. Study outcomes were calculated using a random-effects meta-analysis model.

RESULTS

A total of 8 observational studies with 1,819 patients (median age 67 years; prostate-specific antigen 7.1 mg/ml; prostate volume 36 ml) followed over a median of 24 months were included. The mean prostate-specific antigen nadir following visually directed focal HIFU was 2.2 ng/ml (95% CI 0.9-3.5 ng/ml), achieved after a median of 6 months post-treatment. A clinically significant positive biopsy was identified in 19.8% (95% CI 12.4-28.3%) of cases. Salvage treatment rates were 16.2% (95% CI 9.7-23.8%) for focal- or whole-gland treatment, and 8.6% (95% CI 6.1-11.5%) for whole-gland treatment. Complication rates were 16.7% (95% CI 9.9-24.6%) for de novo erectile dysfunction, 6.2% (95% CI 0.0-19.0%) for urinary retention, 3.0% (95% CI 2.1-3.9%) for urinary tract infection, 1.9% (95% CI 0.1-5.3%) for urinary incontinence, and 0.1% (95% CI 0.0-1.4%) for bowel injury.

CONCLUSION

Limited evidence from eight observational studies demonstrated that visually directed HIFU for focal treatment of localized prostate cancer was associated with a relatively low risk of complications and acceptable cancer control over medium-term follow-up. Comparative, long-term safety and effectiveness results with visually directed focal HIFU are lacking.

Imaging of prostate cancer: optimizing affinity to prostate specific membrane antigen by spacer modifications in a tumor spheroid model

Early diagnosis of prostate cancer (PCa) is crucial for staging, treatment and management of patients. Prostate specific membrane antigen (PSMA), highly over-expressed on PCa cells, is an excellent target for selective imaging of PCa. In recent years, various scaffolds have been explored as potential carriers to target diagnostic and therapeutic agents to PSMA⁺ tumour cells. Numerous fluorescent or radioisotope probes linked via a peptide linker have been developed that selectively binds to PCa cells. However, there are very few reports that examine the effects of chemical modifications in the peptide linker of an imaging probe on its affinity to PSMA protein. This report systematically investigates the impact of hydrophobic aromatic moieties in the peptide linker on PSMA affinity and in vitro performance. For this, a series of fluorescent bioconjugates 12-17 with different aromatic spacers were designed, synthesized, and their interactions within the PSMA pocket were first analysed in silico. Cell uptake studies were then performed for 12-17 in PSMA⁺ cell lines and 3D tumour models in vitro. Binding affinity values of 12-17 were found to be in the range of 36 to 157.9 nM, and 12 with three aromatic groups in the spacer exhibit highest affinity (K_D = 36 nM) compared to 17 which is devoid of aromatic groups. These studies suggest that aromatic groups in the spacer region can significantly affect deep tissue imaging of fluorescent bioconjugates. Bioconjugate 12 can be a promising diagnostic tool, and conjugation to near-infrared agents would further its applications in deep-tissue imaging and surgery. Communicated by Ramaswamy H. Sarma.

State-of-the-art uroradiologic imaging in the diagnosis of prostate cancer

In the diagnostic process of prostate cancer, several radiologic imaging modalities significantly contribute to the detection and localization of the disease. These range from transrectal ultrasound (TRUS) and magnetic resonance imaging (MRI) to positron emission tomography (PET). Within this review, after evaluation of the literature, we will discuss the advantages and disadvantages of these imaging modalities in clarifying the patient's clinical status as to whether he has prostate cancer or not and if so, where it is located, so that therapy appropriate to the patient's disease may be administered. TRUS, specifically with the usage of intravenous contrast agents, provides an excellent way of directing biopsy towards suspicious areas within the prostate in the general (screening) population. MRI using functional imaging techniques allows for highly accurate detection and localization, particularly in patients with prior negative ultrasound guided biopsies. A promising new development is the performance of biopsy within the magnetic resonance scanner. Subsequently, a proposal for optimal use of radiologic imaging is presented and compared with the European and American urological guidelines on prostate cancer.

Locally advanced prostate cancer: the role of surgical management

Among the heterogeneous population of patients with prostate cancer, a high-risk group with locally advanced prostate cancer (LAPC) present a diagnostic and therapeutic dilemma. Although the incidence of LAPC has decreased with screening since the introduction of prostate-specific antigen (PSA) testing, significantly many patients are still diagnosed with LAPC. These patients are by definition at higher risk of metastatic disease and worse outcomes. The role of radical prostatectomy (RP) in this population has been debated, as the combination of radiotherapy and hormonal therapy is becoming used more frequently for LAPC. Unfortunately, the clinical staging and evaluation of LAPC is a challenge that results in possibly understaging or overstaging these patients. This further complicates therapeutic decision-making, and as a result no established standard treatment has been proposed. Like other patients with prostate cancer, individualized therapeutic choices are essential and depend on a multitude of factors. Herein we examine the role of RP for managing LAPC and attempt to emphasize how the risk of distant disease and difficulty with clinical staging might favour incorporating a surgical approach as part of the therapy for patients with LAPC.

Minimally-invasive technologies in uro-oncology: the role of cryotherapy, HIFU and photodynamic therapy in whole gland and focal therapy of localised prostate cancer

The use of minimally-invasive ablative therapies in localised prostate cancer offer potential for a middle ground between active surveillance and radical therapy. This article reviews the evidence for cryotherapy, high intensity focused ultrasound (HIFU) and photodynamic therapy in the treatment of localised prostate cancer. These ablative technologies can deliver a minimally invasive, day case treatment with effective early cancer control and low genitourinary morbidity. In addition, all have the ability to deliver focal therapy of only the malignant lesions within the prostate.

Role of the renin-angiotensin system in prostate cancer

Prostate cancer is highly prevalent in Western society, and its early stages can be controlled by androgen ablation therapy. However, the cancer eventually regresses to an androgen-independent state for which there is no effective treatment. The renin-angiotensin system (RAS), in particular the octapeptide angiotensin II, is now recognised to have important effects on growth factor signalling and cell growth in addition to its well known actions on blood pressure, fluid homeostasis and electrolyte balance. All components of the RAS have been recently identified in the prostate, consistent with the expression of a local RAS system in this tissue. This review focuses on the role of the RAS in the prostate, and the possibility that this pathway may be a potential therapeutic target for the treatment of prostate cancer and other prostatic diseases.

Active surveillance and radical therapy in prostate cancer: can focal therapy offer the middle way?

INTRODUCTION

Focal therapy for prostate cancer is a radical paradigm shift in the management of men with localised prostate cancer. It involves locating and destroying only the areas of prostate cancer whilst leaving the majority of the prostate untreated. By doing so, it is proposed that side-effects of traditional whole-gland therapies such as impotence, incontinence and rectal toxicity will be significantly reduced and cancer control will be at similar levels.

METHODS AND MATERIALS

A Medline/Pubmed search was conducted between 1 May 1998 and 1 May 2008 using the following terms: 'focal therapy', 'lumpectomy', 'hemiablation', 'laterality', 'multifocal', 'unifocal' and 'index lesion' alongside 'prostate cancer'. Articles were selected for their relevance to this review. Abstracts from international conferences over the last 5 years were also used where appropriate. Authors' personal bibliography was used to supplement the review.

CONCLUSIONS

A number of case series have reported significantly lower incontinence and impotence rates using focal cryoablation and one series on focal HIFU. The reporting quality has been variable and there are currently ongoing clinical trials with IRB approval in the USA and UK. Long term follow-up is required. Focal therapy is an exciting new area of research that could hold great promise for men with localised low to intermediate risk prostate cancer.

Will focal therapy become a standard of care for men with localized prostate cancer?

The current treatment choice for men with localized prostate cancer lies between active surveillance and radical therapy. The difference between these two extremes of care is 5% in terms of cancer-related absolute mortality at 8 years. It is generally accepted that this small difference will decrease for men diagnosed in the prostate-specific-antigen era. Radical therapy is associated with considerable adverse effects (e.g. incontinence, impotence, rectal problems) because it treats the whole gland, and damages surrounding structures in up to half of men. Men are being diagnosed at a younger age with lower-risk disease, and many have unifocal or unilateral disease. We propose a new concept whereby only the tumor focus and a margin of normal tissue are treated. This paradigm might decrease adverse effects whilst, at the same time, retaining effective cancer control. The arguments for and against active surveillance and radical therapy are reviewed in this article, with focal therapy presented as a means for bridging these two approaches.

Choices for Surgery

Surgical treatment of prostate cancer has seen many improvements in the past two decades, including laparoscopy, robotic surgery, and better assessment of quality of life and functional results. The limits of surgery for locally advanced disease and after failure of radiotherapy have been better defined, together with the roles of neoadjuvant and adjuvant treatment. Patients with clinically organ-confined prostate cancer, reasonable life expectancy, and little or no co-morbidity are the best candidates for radical prostatectomy. This chapter reviews the different technical options for the treatment of prostate cancer, with their respective indications and functional and oncological results.

Optimal treatment of locally advanced prostate cancer

The treatment of clinically locally advanced prostate cancer (cT3-4) is subject to controversies. Patients with lymph node metastases as well as patients with overstaged localized and thus curable disease fall into this category. Radical prostatectomy, external beam radiotherapy and early or deferred hormonal therapy are possible treatment options. Multimodal treatment (i.e., a combination of these options) is frequently used. After radical prostatectomy, Gleason score-adjusted disease-specific survival does not differ meaningfully between the tumor stages pT2 and pT3-4. In the case of lymph node metastases after radical prostatectomy, but not in node-negative disease, adjuvant hormonal treatment seems to improve survival. Adjuvant radiotherapy may improve biochemical and local control in locally advanced prostate cancer, a survival benefit has, however, not yet been proven. External beam radiotherapy alone provides unfavourable survival rates in locally advanced prostate cancer. Adjuvant hormonal treatment may improve outcome in this setting. When no curative treatment is chosen, early hormonal treatment seems to provide modest benefit compared with deferred therapy.

Tumour volume and high grade tumour volume are the best predictors of pathologic stage and biochemical recurrence after radical prostatectomy

INTRODUCTION

Our goal was to examine to what extent tumour volume (TV) and percentage of high grade tumour volume (%HGTV) affect the rate of positive surgical margins and the rate of biochemical recurrence after radical prostatectomy.

MATERIALS AND METHODS

TV and %HGTV were routinely planimetrically quantified in a cohort of 780 consecutive patients. Mean follow-up was 46.7 months. Multivariable regression models addressed two separate endpoints: positive surgical margins and biochemical recurrence. The increase in model predictive accuracy related to the addition of TV and %HGTV to radical prostatectomy stage and grade was assessed, after 200 bootstrap resamples to reduce overfit bias.

RESULTS

In multivariable logistic regression models addressing positive surgical margins rate, predictive accuracy increased by 1.9% (p<0.001) when TV was added to other covariates. No further increment was noted when %HGTV was added (p=0.3). In multivariable Cox regression models addressing biochemical recurrence, accuracy increased by 0.6% (p=0.002) when TV was added and an additional increase of 0.7% was recorded when %HGTV (p<0.001) was added.

CONCLUSION

Tumour bulk reflected by TV affects local cancer control rate, which is reflected in the rate of positive surgical margins. Conversely, high grade cancer determines the rate of biochemical recurrence. These two variables represent the most powerful predictors of cancer control in men treated for localised prostate cancer. Moreover, they increase the ability of established predictors to predict the outcomes of interest. In consequence, they warrant consideration in future predictive and prognostic tools.

A Pelvic Drain Can Often Be Avoided After Radical Retropubic Prostatectomy—An Update in 552 Cases

OBJECTIVES

The routine placement of a pelvic drain following radical retropubic prostatectomy (RRP) may not be required. We describe our experience in 552 consecutive RRPs to emphasise the safety of this approach and explain our rationale for avoiding a drain when possible.

METHODS

RRP was performed in 552 consecutive patients with clinically localised adenocarcinoma of the prostate between January 2002 and June 2005. Clinical and pathologic information was documented for each patient. After the prostate was removed and the anastomotic sutures tied, the bladder was gently filled with approximately 50 ml of saline through the urethral catheter. If there was no leak, a drain was not placed.

RESULTS

A drain was not placed in 419 (76%) of the 552 patients. We compared the postoperative complication rates in those with (D+) and without (D-) a drain. There were 27 (5%) immediate postoperative complications and no significant difference between the two groups (D+, 6%; D-, 5%; p=0.629): three (1%) patients who did not have a drain had a urinoma, one (1%) who had a drain had a lymphocele, and two (2%) who had a drain had a small pelvic haematoma.

CONCLUSIONS

If the bladder neck is preserved or meticulously reconstructed, there may be little extravasation and, thus, routine drainage is unnecessary. Our 4-year experience indicates that morbidity is not increased by omitting a drain from the pelvic cavity after RRP in properly selected cases.

Treatment of Locally Advanced Prostate Cancer – The Case for Radical Prostatectomy

The treatment of clinically locally advanced prostate carcinoma (stage cT3) remains controversial. One of the main reasons for this controversy results from the substantial staging error attached to the clinical diagnosis cT3 with overstaged T2 tumors and understaged node-positive cases. Treatment options in this situation include radical prostatectomy, external beam radiotherapy, immediate or delayed androgen deprivation treatment and the so-called 'watchful waiting'. Acceptable and often surprisingly good tumor-specific survival rates have been reported for radical prostatectomy in pT3 series--based on good clinical case selection--approaching those of pT2 series. In lymph node-positive pT3 cases, adjuvant hormone deprivation seems to prolong survival which it does not in lymph node-negative pT3 disease. A benefit of adjuvant external beam radiotherapy after radical prostatectomy for pT3 cases in prolonging overall survival has not been shown, despite the fact that it can prevent or delay biochemical and local recurrence. External beam radiotherapy as the only treatment for cT3 disease results in unfavorable tumor-specific survival rates, which can be significantly improved with adjuvant hormonal treatment with LHRH agonists. If, in case of advanced age and/or significant comorbidity, primary hormonal treatment is chosen, early hormonal deprivation therapy seems to offer marginal benefits in survival compared to delayed treatment.

Clinical Approach to the Prostate: An Update

Prostatic disease continues to present clinicians with challenges. Although giant strides have been made in the medical and surgical management of benign prostatic hyperplasia, many fundamental questions about its pathogenesis, progression, and treatment efficacy remain unanswered. Prostate cancer also continues to be an area in which progress is needed despite major recent advancements. Numerous debates that include the value of prostate-specific antigen screening and appropriate roles for each of the numerous therapeutic modalities await resolution. For millions of patients who suffer from prostatitis, a major breakthrough is yet to come. Current treatment regimens for prostatitis remain ineffective at best. Contemporary approaches to the pathogenesis, diagnosis, and treatment of benign prostatic hyperplasia, prostate cancer, and prostatitis are discussed in this review.

Management of prostate cancer. Part 2: localized and locally advanced disease

Prostate cancer is the most prevalent nondermatological malignancy affecting men in the Western world. An increase in public awareness has led to earlier detection. Accepted treatments for localized prostate cancer include active surveillance, radical prostatectomy, interstitial brachytherapy, external beam radiotherapy and watchful waiting. The authors discuss the rationale for the different approaches together with outcomes including toxicity. Novel approaches are also explored. The management of locally advanced disease has long been a challenge and the evolving evidence is reviewed.

Free and total human glandular kallikrein 2 in patients with prostate cancer

OBJECTIVES

The use of prostate-specific antigen (PSA, hK3) results in the overdiagnosis and overtreatment of prostate cancer. Markers are needed that could identify aggressive, fast-growing tumors and help decide which patients would benefit most from aggressive treatment. Human glandular kallikrein 2 (hK2) could be such a marker. The aim of this study was to test how PSA and hK2 could predict the pathologic stage and grade in a set of patients with clinically organ-confined disease.

METHODS

Heparin plasma was collected from 188 patients who had undergone radical prostatectomy at the Turku University Central Hospital. Total and free PSA, as well as total and free hK2, were measured and the results compared with the pathologic TNM stage, tumor World Health Organization grade, and Gleason score.

RESULTS

Free and total hK2 performed similarly to PSA in their ability to separate groups of patients with different stages or grades. Concentrations of both kallikreins were significantly different in patients with World Health Organization grade 1 cancer compared with grade 2. Neither marker could separate patients with different Gleason scores. Although PSA concentrations increased most between patients with Stage pT2b and those with pT3a, the increase in hK2 was most pronounced between those with Stage pT3a and those with pT3b.

CONCLUSIONS

Although hK2 could not predict the cancer stage or grade better than PSA, changes in the hK2 and PSA concentrations occurred at different points in cancer progression. hK2 may have a role in the prognosis of prostate cancer, but additional studies with longer follow-up are required to determine whether hK2 can help when selecting treatment options.

Non-Cancer Mortality among People Diagnosed with Cancer (Australia)

OBJECTIVE

To investigate whether people diagnosed with cancer have an increased risk of death from non-cancer causes compared to the general population.

METHODS

The non-cancer mortality of people diagnosed with cancer in Queensland (Australia) between 1982 and 2002 who had not died before 1 January 1993 was compared to the mortality of the total Queensland population, matching by age group and sex, and reporting by standardised mortality ratios.

RESULTS

Compared to the non-cancer mortality in the general population, cancer patients (all cancers combined) were nearly 50% more likely to die of non-cancer causes (SMR = 149.9, 95% CI = [147-153]). This varied by cancer site. Overall melanoma patients had significantly lower non-cancer mortality, female breast cancer patients had similar non-cancer mortality to the general population, while increased non-cancer mortality risks were observed for people diagnosed with cervical cancer, colorectal cancer, prostate cancer, non-Hodgkin lymphoma and lung cancer.

CONCLUSIONS

Although cancer-specific death rates underestimate the mortality directly associated with a diagnosis of cancer, quantifying the degree of underestimation is difficult due to various competing explanations. There remains an important role for future research in understanding the causes of morbidity among cancer survivors, particularly those looking at both co-morbid illnesses and reductions in quality of life.

[Treatment of locally advanced prostate cancer]

The management of clinically locally advanced prostate carcinoma (cT3) remains a controversial issue. The clinical stage cT3 consists of a mixture of overstaged T2 carcinomas but also contains lymph node-positive cases. Treatment options consist of radical prostatectomy, external beam radiotherapy, hormonal deprivation (early or delayed) and the so-called watchful waiting. In many cases multimodal therapy is used. Radical prostatectomy in the clinical stage T3 can achieve acceptable tumour-specific survival rates if patients are well selected. In this way, tumour-specific survival rates can be reached for pT3 patients which closely approach those of pT2 cases. In lymph node-positive cases after radical prostatectomy adjuvant hormonal treatment can prolong survival, but not in lymph node-negative cases. A benefit of adjuvant radiotherapy after radical prostatectomy has not been proven. Although it can postpone or prevent biochemical recurrence, it does not prolong overall survival. Treatment of stage cT3 by external beam radiotherapy alone results in unfavourable tumour-specific survival rates. In these cases definite improvement can be achieved by adjuvant androgen deprivation with LHRH analogues. If in case of severe comorbidity or advanced age primary hormonal treatment is chosen, early vs deferred treatment seems to prolong survival marginally.