Contrast enhancement on computed tomography after renal cryoablation: an evidence of treatment failure?

BACKGROUND AND PURPOSE

Renal cryoablation has gained popularity as a treatment option for localized renal masses. Treatment success is typically defined by the absence of contrast enhancement on follow-up imaging. We investigate the evolution of lesions that demonstrate contrast enhancement on CT after renal cryoablation.

PATIENTS AND METHODS

Retrospective review of records of laparoscopic and percutaneous cryoablation (LCA and PCA) was performed, identifying records with postoperative radiographic enhancement. Imaging studies were reviewed and radiographic (pre- and post-contrast Hounsfield units, pattern and location of enhancement) and clinical data including follow up were collected.

RESULTS

One hundred and seventy-two cryoablation procedures were analyzed. Of these, 30 (17.4%) showed enhancement on follow-up CT. In 28 cases, contrast enhancement was demonstrated on the first postoperative study. Seven patients underwent salvage treatments. Spontaneous resolution of enhancement was noted in 17 (56.7%) cases. No association was found between enhancement pattern (diffuse/nodular/rim) and resolution. Of lesions enhancing >35 HU, only 14.3% resolved spontaneously. Delayed enhancement (after negative imaging studies) occurred in two patients; both underwent salvage treatments.

CONCLUSIONS

Most of the time, contrast-enhancements after cryoablation are evident on the first follow-up imaging study. More than 50% of these resolve spontaneously, and only one of four patients need salvage treatment. Delayed appearance of enhancement after previously negative imaging and highly enhancing lesions (>35 HU) are unlikely to resolve and should be considered suspicious for local recurrence or incomplete ablation. Further investigation is warranted to reach a consensus on a radiographic definition of local recurrence after renal cryoablation.

Acoustic radiation force impulse imaging of human prostates: initial in vivo demonstration

Reliably detecting prostate cancer (PCa) has been a challenge for current imaging modalities. Acoustic radiation force impulse (ARFI) imaging is an elasticity imaging method that uses remotely generated, focused acoustic beams to probe tissue stiffness. A previous study on excised human prostates demonstrated ARFI images portray various prostatic structures and has the potential to guide prostate needle biopsy with improved sampling accuracy. The goal of this study is to demonstrate the feasibility of ARFI imaging to portray internal structures and PCa in the human prostate in vivo. Custom ARFI imaging sequences were designed and implemented using a modified Siemens Antares™ scanner with a three-dimensional (3-D) wobbler, end-firing, trans-cavity transducer, EV9F4. Nineteen patients were consented and imaged immediately preceding surgical prostatectomy. Pathologies and anatomic structures were identified in histologic slides by a pathologist blinded to ARFI data and were then registered with structures found in ARFI images. The results demonstrated that when PCa is visible, it generally appears as bilaterally asymmetric stiff structures; benign prostatic hyperplasia (BPH) appears heterogeneous with a nodular texture; the verumontanum and ejaculatory ducts appears softer compared with surrounding tissue, which form a unique 'V' shape; and the boundary of the transitional zone (TZ) forms a stiff rim separating the TZ from the peripheral zone (PZ). These characteristic appearances of prostatic structures are consistent with those found in our previous study of prostate ARFI imaging on excised human prostates. Compared with the matched B-mode images, ARFI images, in general, portray prostate structures with higher contrast. With the end-firing transducer used for this study, ARFI depth penetration was limited to 22 mm. Image contrast and resolution were decreased as compared with the previous ex vivo study due to the small transducer aperture. Even with these limitations, this study suggests ARFI imaging holds promise for guidance of targeted prostate needle biopsy and focal therapy, as well as aiding assessment of changes during watchful waiting/active surveillance.

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

INTRODUCTION

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

AIM

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

METHODS

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

MAIN OUTCOME MEASURES

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

RESULTS

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

CONCLUSIONS

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

Utilization trends at a multidisciplinary prostate cancer clinic: initial 5-year experience from the Duke Prostate Center

PURPOSE

The multidisciplinary approach is becoming increasingly encouraged but little is known about the multidisciplinary experience compared to routine care. For patients with prostate cancer the goal is to provide evaluations by urologists, medical and radiation oncologists at a single visit. Although additional resources are required, this strategy may enhance the overall health care experience. We compared utilization determinants between a multidisciplinary and a urology prostate cancer clinic at Duke University Medical Center and identified factors associated with pursuing treatment at the university medical center for multidisciplinary clinic patients.

MATERIALS AND METHODS

We retrospectively analyzed data on patients referred for primary prostate cancer treatment evaluation at Duke University Medical Center from 2005 to 2009. Comparisons between 701 multidisciplinary clinic and 1,318 urology prostate cancer clinic patients were examined with the rank sum and chi-square tests. Predictive factors for pursuing treatment at the university medical center were assessed using multivariate adjusted logistic regression.

RESULTS

Compared to patients at the urology prostate cancer clinic those at the multidisciplinary clinic were more likely to be younger and white, have a higher income and travel a longer distance for evaluation. Of multidisciplinary clinic patients 58% pursued primary treatment at the university medical center. They were more likely to be younger, black and physician referred, have a lower income and reside closer to the medical center. Factors predictive of pursuing treatment at the medical center included high risk disease and physician referral. Factors predictive of not receiving care at the university medical center were income greater than $40,000 and a distance traveled of greater than 100 miles.

CONCLUSIONS

A different patient demographic is using the multidisciplinary approach. However, when treatment is pursued at the institution providing multidisciplinary services, the patient demographic resembles that of the treating institution.

Transatlantic Consensus Group on active surveillance and focal therapy for prostate cancer

What's known on the subject? and What does the study add? Active surveillance for prostate cancer is gaining increasing acceptance for low risk prostate cancer. Focal therapy is an emerging tissue preservation strategy that aims for treat only areas of cancer. Early phase trials have shown that side-effects can be significantly reduced using focal therapy. There is significant uncertainty in both active surveillance and focal therapy. This consensus group paper provides a road-map for clinical practice and research for both tissue-preserving strategies in the areas of patient population, tools for risk stratification and cancer localisation, treatment interventions as well as comparators and outcome measures in future comparative trials.

OBJECTIVE

To reach consensus on key issues for clinical practice and future research in active surveillance and focal therapy in managing localized prostate cancer.

PATIENTS AND METHODS

A group of expert urologists, oncologists, radiologists, pathologists and computer scientists from North America and Europe met to discuss issues in patient population, interventions, comparators and outcome measures to use in both tissue-preserving strategies of active surveillance and focal therapy. Break-out sessions were formed to provide agreement or highlight areas of disagreement on individual topics which were then collated by a writing group into statements that formed the basis of this report and agreed upon by the whole Transatlantic Consensus Group.

RESULTS

The Transatlantic group propose that emerging diagnostic tools such as precision imaging and transperineal prostate mapping biopsy can improve prostate cancer care. These tools should be integrated into prostate cancer management and research so that better risk stratification and more effective treatment allocation can be applied. The group envisaged a process of care in which active surveillance, focal therapy, and radical treatments lie on a continuum of complementary therapies for men with a range of disease grades and burdens, rather than being applied in the mutually exclusive and competitive way they are now.

CONCLUSION

The changing landscape of prostate cancer epidemiology requires the medical community to re-evaluate the entire prostate cancer diagnostic and treatment pathway in order to minimize harms resulting from over-diagnosis and over-treatment. Precise risk stratification at every point in this pathway is required alongside paradigm shifts in our thinking about what constitutes cancer in the prostate.

Effect of low-fat diets on plasma levels of NF-κB-regulated inflammatory cytokines and angiogenic factors in men with prostate cancer

Diet, nutritional status, and certain dietary supplements are postulated to influence the development and progression of prostate cancer. Angiogenesis and inflammation are central to tumor growth and progression, but the effect of diet on these processes remains uncertain. We explored changes in 50 plasma cytokines and angiogenic factors (CAF) in 145 men with prostate cancer enrolled in a preoperative, randomized controlled phase II trial with four arms: control (usual diet), low-fat (LF) diet, flaxseed-supplemented (FS) diet, and FS+LS diet. The mean duration of dietary intervention was 30 to 31 days. Among the individual arms, the largest number of significant changes (baseline vs. preoperative follow-up) was observed in the LF arm, with 19 CAFs decreasing and one increasing (P < 0.05). Compared with the control arm, 6 CAFs-including proangiogenic factors (stromal-cell derived-1α) and myeloid factors (granulocyte-colony-stimulating factor, macrophage colony-stimulating factor)-all decreased in the LF arm compared with controls; three and four CAFs changed in the FS and FS+LF arms, respectively. Weight loss occurred in the LF arms and significantly correlated with VEGF decreases (P < 0.001). The CAFs that changed in the LF arm are all known to be regulated by NF-κB, and a pathway analysis identified NF-κB as the most likely regulatory network associated with these changes in the LF arm but not in the FS-containing arms. These results suggest that a LF diet without flaxseed may reduce levels of specific inflammatory CAFs and suggests that the NF-κB pathway may be a mediator of these changes.

Treatment of localised renal cell carcinoma

CONTEXT

The increasing incidence of localised renal cell carcinoma (RCC) over the last 3 decades and controversy over mortality rates have prompted reassessment of current treatment.

OBJECTIVE

To critically review the recent data on the management of localised RCC to arrive at a general consensus.

EVIDENCE ACQUISITION

A Medline search was performed from January 1, 2004, to May 3, 2011, using renal cell carcinoma, nephrectomy (Medical Subject Heading [MeSH] major topic), surgical procedures, minimally invasive (MeSH major topic), nephron-sparing surgery, cryoablation, radiofrequency ablation, surveillance, and watchful waiting.

EVIDENCE SYNTHESIS

Initial active surveillance (AS) should be a first treatment option for small renal masses (SRMs) <4 cm in unfit patients or those with limited life expectancy. SRMs that show fast growth or reach 4 cm in diameter while on AS should be considered for treatment. Partial nephrectomy (PN) is the established treatment for T1a tumours (<4 cm) and an emerging standard treatment for T1b tumours (4-7 cm) provided that the operation is technically feasible and the tumour can be completely removed. Radical nephrectomy (RN) should be limited to those cases where the tumour is not amenable to nephron-sparing surgery (NSS). Laparoscopic radical nephrectomy (LRN) has benefits over open RN in terms of morbidity and should be the standard of care for T1 and T2 tumours, provided that it is performed in an advanced laparoscopic centre and NSS is not applicable. Open PN, not LRN, should be performed if minimally invasive expertise is not available. At this time, there is insufficient long-term data available to adequately compare ablative techniques with surgical options. Therefore ablative therapies should be reserved for carefully selected high surgical risk patients with SRMs <4 cm.

CONCLUSIONS

The choice of treatment for the patient with localised RCC needs to be individualised. Preservation of renal function without compromising the oncologic outcome should be the most important goal in the decision-making process.

Radiation-induced erectile dysfunction using prostate-confined modern radiotherapy in a rat model

INTRODUCTION

The mechanisms of radiation-induced erectile dysfunction (ED) are unclear, as clinical studies are limited, and previous animal models were based on wide-field irradiation, which does not model current radiotherapy (RT) techniques.

AIMS

To perform functional and morphological analyses of erectile function (EF) utilizing image-guided stereotactic prostate-confined RT in a rat model.

METHODS

Sixty young adult male rats aged 10-12 weeks old were divided into age-matched sham and RT groups. A single 20-Gy fraction to the prostate was delivered to RT animals. Penile bulb, shaft, and testes were excluded from treatment fields.

MAIN OUTCOME MEASURES

Bioassay and intracavernous pressure (ICP) measurements were conducted at 2, 4, and 9 weeks following RT. Perfusion analysis of the corpora cavernosa (CC) was conducted using Hoechst injected prior to sacrifice. Penile shaft and cavernous nerve (CN) were evaluated by immunohistochemistry. Plasma testosterone level was analyzed using a testosterone enzyme-linked immunosorbent assay (ELISA) assay kit.

RESULTS

Irradiated animals demonstrated statistically significant time-dependent functional impairment of EF by bioassay and ICP measurement from 4 weeks. Neuronal nitric oxide synthase (NOS) expression was decreased in CN by 4 weeks. In CC, expression levels of anti-alpha smooth muscle actin and endothelial NOS were significantly decreased at 9 weeks. In penile dorsal vessels, smooth muscle/collagen ratio was significantly decreased at 4 and 9 weeks. Additionally, Hoechst perfusion showed time-dependent decrease in CC of RT animals, whereas CD31 expression was not affected. No toxicities were noted; testosterone levels were similar in both groups.

CONCLUSION

We demonstrated time-dependent ED following image-guided stereotactic RT. Our results imply that reduction of neuronal NOS expression in cavernous nerve could trigger consecutive reduction of smooth muscle content as well as blood perfusion in CC that resulted in corporal veno-occlusive dysfunction. Present study could be a cornerstone to future research that may bring comprehensive scientific understanding of radiation-induced ED.

Cigarette Smoking Is Associated With Advanced Renal Cell Carcinoma

Purpose

Cigarette smoking is a recognized risk factor for renal cell carcinoma (RCC), but little data are available on the association between smoking and RCC biology. We investigated the association between cigarette smoking and RCC stage in a large contemporary multiethnic surgical cohort.

Patients and Methods

We retrospectively reviewed the demographic, clinical, and pathologic data of patients undergoing surgery for RCC between 2000 and 2009. Advanced RCC was defined as metastatic disease, pathologic stage ≥ T3, and/or lymph node involvement. Self-reported smoking history included smoking status, duration, intensity, cumulative exposure, and cessation. Patient and tumor characteristics were compared between the groups in univariate and multivariate analyses.

Results

Of the 845 eligible patients, 19.4% and 29.1% were current and former smokers, respectively, and 207 patients (24.5%) had advanced disease. In both univariate and multivariate analyses, smoking was consistently associated with advanced RCC, and cessation reversed the risk. Current and former smokers had 1.5- and 1.6-fold increased odds of advanced disease, respectively. Heavier smoking (longer duration and exposure) was associated with increased risk of advanced RCC, whereas durable cessation reduced the odds of advanced disease.

Conclusion

Cigarette smoking is an independent risk factor for advanced RCC. Heavier smoking increases the likelihood of advanced disease. Durable smoking cessation attenuated the risk of advanced disease. Given that cigarette smoking is among the few modifiable risk factors for RCC, our results reinforce the importance of smoking cessation and encourage further investigation of the association between smoking and RCC biology.

Adjuvant versus salvage radiation therapy for prostate cancer and the risk of death

OBJECTIVE

To investigate whether salvage radiation therapy (RT) for prostate-specific antigen (PSA) failure can provide the same result as adjuvant RT, which decreases the risk of all-cause mortality (ACM) for men with positive margins (R1), or extra-capsular or seminal vesicle extension (pT3).

METHODS

We studied 1638 men at Duke University who underwent radical prostatectomy for unfavourable-risk prostate cancer and whose postoperative PSA was undetectable. Cox regression was used to evaluate whether salvage vs adjuvant RT in men with a rapid (<10 months) or slow (≥10 months) PSA doubling time (DT) was associated with the risk of ACM, adjusting for adverse features (pT3, R1, Gleason score 8-10), age, preoperative PSA level, comorbidity and hormonal therapy use.

RESULTS

Despite fewer men with two or more adverse features (61 vs 82%; P=0.016), salvage for a rapid PSA DT vs adjuvant RT increased the risk of ACM [adjusted hazard ratio (AHR)=3.42; 95% confidence interval (CI)=1.27-9.20; P=0.015]. There was no difference (AHR=1.39; 95% CI=0.50-3.90; P=0.53) in the risk of ACM among men who received salvage for a slow PSA DT or adjuvant RT. Nearly all (90%) men with a slow PSA DT had Gleason score ≤7 and the majority (59%) had at most pT3 or R1 disease.

CONCLUSION

Radiation therapy after PSA failure as compared with adjuvant RT was not associated with an increased risk of ACM in men with Gleason score ≤7 and pT3R0 or pT2R1 disease.

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

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Altered male physiologic function after surgery for prostate cancer: couple perspective

PURPOSE

Both the diagnosis of prostate cancer (PCa) and the physiologic outcomes of surgical treatment impact the male's psychological sphere. However, current research advocates a refocusing of outcomes directed to the PCa "couple". Herein we acquire insight into perspective and concordance regarding male physiological function from the standpoint of a couple recovering from PCa surgery.

MATERIALS AND METHODS

Couples whereby the male partner had undergone primary surgical treatment for PCa were mailed a Retrospective Sexual Survey (RSS) packet consisting of male and female partner questionnaires. RSS questions surveyed physiological changes in libido, foreplay, erection and arousal, orgasm and ejaculation in addition to perceived psychological impact. Patients' and partners' scores were evaluated to determine the concordance of both individual items as well as domain sums.

RESULTS

Twenty-eight couples completed the questionnaires. Only about 40% of men and women were happy with their levels of sexual interest with 82% concordance. Urine loss during orgasm was reported by 43% of men; the majority of participants were bothered by it. Ejaculation changes were observed by 96% of men (concordance 96%) with most reporting anejaculation. A change in orgasm experience was noted by 86% of men (and 36% of their female partners, p < 0.0001). Despite the change, the majority of men and women reported being satisfied with their ability to climax.

CONCLUSION

Our results indicate that patients and their female partners may interpret differently the same physiological outcomes of PCa surgery. This information could be useful to better counsel the PCa couple and help patients and partners adjust after surgery.