Ligand-gated ion channels as potential biomarkers for ADT-mediated cognitive decline in prostate cancer patients

Men with prostate cancer are at increased risk of developing cognitive decline by the use of second-generation androgen signaling inhibitors. To date, reliable and sensitive biomarkers that could distinguish men at high risk of cognitive dysfunction under androgen deprivation therapy (ADT) have not been characterized. We used high-throughput transcriptional profiling utilizing human prostate cancer cell culture models mimicking ADT, biomarker selection using minimal common oncology data elements-cytoscape, and bioinformatic analyses employing Advaita® iPathwayGuide and DisGeNET for identification of disease-related gene associations. Validation analysis of genes was performed on brain neuronal and glial cells by quantitative real-time polymerase chain reaction assay. Our systematic analysis of androgen deprivation-associated genes involved multiple biological processes, including neuroactive ligand-receptor interaction, axon guidance, cytokine-cytokine receptor interaction, and metabolic and cancer signaling pathways. Genes associated with neuroreceptor ligand interaction, including gamma-aminobutyric acid (GABA) A and B receptors and nuclear core proteins, were identified as top upstream regulators. Functional enrichment and protein-protein interaction network analysis highlighted the role of ligand-gated ion channels (LGICs) and their receptors in cognitive dysfunction. Gene-disease association assigned forgetfulness, intellectual disability, visuospatial deficit, bipolar disorder, and other neurocognitive impairment with upregulation of type-1 angiotensin II receptor, brain-derived neurotrophic factor, GABA type B receptor subunit 2 (GABBR2), GABRA3, GABRA5, GABRB1, glycine receptor beta, glutamate ionotropic receptor N-methyl-D-aspartate receptor (NMDA) type subunit 1, glutamate ionotropic receptor NMDA type subunit 2D, 5-hydroxytryptamine receptor 1D, interferon beta 1, and nuclear receptor subfamily 3 group C member 1 as top differentially expressed genes. Validation studies of brain glial cells, neurons, and patients on ADT demonstrated the association of these genes with cognitive decline. Our findings highlight LGICs as potential biomarkers for ADT-mediated cognitive decline. Further validation of these biomarkers may lead to future practical clinical use.

Five-Year Patient-Reported Outcomes in NRG Oncology RTOG 0938, Evaluating Two Ultrahypofractionated Regimens for Prostate Cancer

PURPOSE

There is considerable interest in very short (ultrahypofractionated) radiation therapy regimens to treat prostate cancer based on potential radiobiological advantages, patient convenience, and resource allocation benefits. Our objective is to demonstrate that detectable changes in health-related quality of life measured by the bowel and urinary domains of the Expanded Prostate Cancer Index Composite (EPIC-50) were not substantially worse than baseline scores.

METHODS AND MATERIALS

NRG Oncology's RTOG 0938 is a nonblinded randomized phase 2 study of National Comprehensive Cancer Network low-risk prostate cancer in which each arm is compared with a historical control. Patients were randomized to 5 fractions (7.25 Gy in 2 week and a day [twice a week]) or 12 fractions (4.3Gy in 2.5 weeks [5 times a week]). Secondary objectives assessed patient-reported toxicity at 5 years using the EPIC. Chi-square tests were used to assess the proportion of patients with a deterioration from baseline of >5 points for bowel, >2 points for urinary, and >11 points for sexual score.

RESULTS

The study enrolled 127 patients to 5 fractions (121 eligible) and 128 patients to 12 fractions (125 eligible). The median follow-up for all patients at the time of analysis was 5.38 years. The 5-year frequency for >5 point change in bowel score were 38.4% (P = .27) and 23.4% (P = 0.98) for 5 and 12 fractions, respectively. The 5-year frequencies for >2 point change in urinary score were 46.6% (P = .15) and 36.4% (P = .70) for 5 and 12 fractions, respectively. For 5 fractions, 49.3% (P = .007) of patients had a drop in 5-year EPIC-50 sexual score of ≥11 points; for 12 fractions, 54% (P < .001) of patients had a drop in 5-year EPIC-50 sexual score of ≥11 points. Disease-free survival at 5 years is 89.6% (95% CI: 84.0-95.2) in the 5-fraction arm and 92.3% (95% CI: 87.4-97.1) in the 12-fraction arm. There was no late grade 4 or 5 treatment-related urinary or bowel toxicity.

CONCLUSIONS

This study confirms that, based on long-term changes in bowel and urinary domains and toxicity, the 5- and 12-fraction regimens are well tolerated. These ultrahypofractionated approaches need to be compared with current standard radiation therapy regimens.

Treatment patterns and survival of low and intermediate-risk prostate cancer in end-stage kidney disease: A retrospective population cohort study

BACKGROUND

In accordance with guidelines, observation with or without active surveillance for low-risk prostate cancer increased in recent years in the general population. We compared treatment patterns and mortality for low- and intermediate-risk prostate cancer and mortality rates among end-stage kidney disease (ESKD) and non-ESKD patients.

METHODS

This is a retrospective population-based observational cohort study of Surveillance, Epidemiology, and End Results-Medicare data of men aged 66 years and older with localized prostate cancer (2004-2015). ESKD status was determined using Medicare billing codes. Multivariable logistic regression models and Cox-proportional hazards models were used to study definitive treatment patterns and mortality, respectively.

RESULTS

For low-risk prostate cancer, dialysis patients (N = 83) had lower but not statistically significant odds (OR, 0.74; 95% CI: 0.48-1.16) of receiving definitive treatment than non-ESKD patients (N = 24,935). For those with intermediate-risk prostate cancer, dialysis patients (N = 254) had lower odds to receive definitive treatment (OR, 0.54; 95% CI: 0.42-0.72) than non-ESKD patients (N = 60,883). From 2004-2010 to 2011-2015, for patients with low-risk prostate cancer, while the receipt of definitive treatment for non-ESKD patients trended down from 72% to 48%, it trended up for dialysis patients from 55% to 65%. Kidney transplant patients (N = 33 for low-risk and N = 91 for intermediate-risk) had lower rates of definitive treatment for low-risk and similar rates of treatment for intermediate-risk prostate cancer compared to non-ESKD patients.

CONCLUSIONS

The disparity in definitive treatment rates for low-risk prostate cancer among dialysis patients exists despite their high mortality, compared to the general population.

Increased cytokine gene expression and cognition risk associated with androgen deprivation therapy

BACKGROUND

Androgen deprivation therapy (ADT) is a standard treatment modality for locally advanced, high-risk, and metastatic hormone-sensitive prostate cancer. Long-term ADT treatment likely develops side-effects that include changes in cognition or onset of dementia. However, the molecular understanding of this effect remains elusive. We attempt to establish a link between ADT and changes in cognitive function using patient databases and bioinformatics analyses.

METHODS

Gene expression profiling was performed using RNA sequencing data from Alzheimer patient cohort and compared with the data from advanced-stage prostate cancer patients receiving neoadjuvant antiandrogen therapy. Differentially expressed genes (DEGs) were analyzed using the Ingenuity knowledge database.

RESULTS

A total of 1952 DEGs in the Alzheimer patient cohort and 101 DEGs were identified in ADT treated prostate cancer patients. Comparing both data sets provided a subset of 33 commonly expressed genes involving cytokine-cytokine signaling with an over representation of cytokine-cytokine receptor interaction, inflammatory cytokines, signaling by interleukins together with alterations in the circulating lymphocyte repertoire, adaptive immune responses, regulation of cytokine production, and changes in T-cell subsets. Additionally, lipopolysaccharide, tumor necrosis factor, and toll-like receptors were identified as upstream transcriptional regulators of these pathways. The most commonly expressed genes viz. IL-17A, CCL2, IL-10, IL-6, IL-1RN, LIF/LIFR were further validated by quantitative RT-PCR exhibited higher expression in antiandrogen treated neuronal, glial, and androgen-responsive prostate cancer cells, compared to no-androgen antagonist treatment.

CONCLUSIONS

Our findings suggest that changes in cytokine signaling under the influence of ADT in prostate cancer patients may be linked with cognitive impairment presenting new avenues for diagnostic and therapeutic development in combating brain deficits.

Human Gut Mycobiome and Fungal Community Interaction: The Unknown Musketeer in the Chemotherapy Response Status in Bladder Cancer

Background

Until recently, the properties of microbiome and mycobiome in humans and its relevance to disease have largely been unexplored. While the interest of microbiome and malignancy over the past few years have burgeoned with advent of new technologies, no research describing the composition of mycobiome in bladder cancer has been done. Deciphering of the metagenome and its aggregate genetic information can be used to understand the functional properties and relationships between the bacteria, fungi, and cancer.

Objective

The aim of this project is to characterize the compositional range of the normal versus bladder cancer mycobiome of the gut.

Design setting and participants

An internal transcribed spacer (ITS) survey of 52 fecal samples was performed to evaluate the gut mycobiome differences between noncancer controls and bladder cancer patients.

Outcome measurements and statistical analysis

Our study evaluated the differences in mycobiome among patients with bladder cancer, versus matched controls. Our secondary analysis evaluated compositional differences in the gut as a function of response status with neoadjuvant chemotherapy. Data demultiplexing and classification were performed using the QIIME v.1.1.1.1 platform. The Ion Torrent-generated fungal ITS sequence data were processed using QIIME (v.1.9.1), and the reads were demultiplexed, quality filtered, and clustered into operation taxonomic units using default parameters. Alpha and beta diversity were computed and plotted in Phyloseq, principal coordinate analysis was performed on Bray-Curtis dissimilarity indices, and a one-way permutational multivariate analysis of variance was used to test for significant differences between cohorts. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was applied to infer functional categories associated with taxonomic composition.

Results and limitations

We found distinctive mycobiome differences between control group (n = 32) and bladder cancer (n = 29) gut flora, and identified an increasing abundance of Tremellales, Hypocreales, and Dothideales. Significant differences in alpha and beta diversity were present between the groups (control vs bladder; p = 0.002), noting distinct compositions within each cohort. A subgroup analysis by sex and neoadjuvant chemotherapy status did not show any further differences in mycobiome composition and diversity. Our results indicate that the gut mycobiome may modulate tumor response to preoperative chemotherapy in bladder cancer patients. We propose that patients with a "favorable" mycobiome composition (eg, high diversity, and low abundance of Agaricomycetes and Saccharomycetes) may have enhanced systemic immune response to chemotherapy through antigen presentation.

Conclusions

Our study is the first to characterize the enteric mycobiome in patients with bladder cancer and describe complex ecological network alterations, indicating complex bacteria-fungi interactions, particularly highlighted among patients with complete neoadjuvant chemotherapy response.

Patient summary

Our study has demonstrated that the composition of stool mycobiome (fungal inhabitants of the gastrointestinal tract) in patients with bladder cancer is different from that in noncancer individuals. Furthermore, when evaluating how patients respond to chemotherapy given prior to their surgery, our study noted significant differences between patients who responded and those who did not.

Melatonin and Prostate Cancer: Anti-tumor Roles and Therapeutic Application

Melatonin is an endogenous indoleamine that has been shown to inhibit tumor growth in laboratory models of prostate cancer. Prostate cancer risk has additionally been associated with exogenous factors that interfere with normal pineal secretory activity, including aging, poor sleep, and artificial light at night. Therefore, we aim to expand on the important epidemiological evidence, and to review how melatonin can impede prostate cancer. More specifically, we describe the currently known mechanisms of melatonin-mediated oncostasis in prostate cancer, including those that relate to the indolamine's ability to modulate metabolic activity, cell cycle progression and proliferation, androgen signaling, angiogenesis, metastasis, immunity and oxidative cell status, apoptosis, genomic stability, neuroendocrine differentiation, and the circadian rhythm. The outlined evidence underscores the need for clinical trials to determine the efficacy of supplemental, adjunct, and adjuvant melatonin therapy for the prevention and treatment of prostate cancer.

Oxidative Stress and Antioxidant Status in High-Risk Prostate Cancer Subjects

The oxidant/antioxidant balance has been implicated in the pathophysiology of prostate cancer. We investigated oxidative damage and antioxidant status in high-risk prostate cancer subjects. Reduced glutathione (GSH) levels were measured in erythrocytes, 8-hydroxydeoxyguanosine (8-OHdG) in leukocytes and plasma levels of catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GSH-R), glutathione S-transferase (GST), superoxide dismutase (SOD), and lipid peroxide products were measured in high-risk and age-matched healthy subjects. Serum PSA levels were significantly higher (p < 0.0001) in high-risk subjects, whereas GST (p < 0.0001) and GSH (p < 0.002) were higher in healthy controls. Levels of 8-OHdG, an oxidized nucleoside of DNA, were significantly increased (p < 0.0001) in high-risk subjects. No marked difference in the levels of CAT (p = 0.237), GSH-Px (p = 0.74), GSH-R (p = 0.344), SOD (p = 0.109), and lipid peroxide products (p = 0129) were observed between two groups. Pearson's correlation between GST and PSA (r = -0.69 (p < 0.0001)), GST and 8-OHdG (r = -0.62 (p < 0.0004)), GSH and 8-OHdG (r= -0.39 (p = 0.038)), and CAT and GSH-Px (r= -0.33 (p = 0.04)) were found to be negatively correlated, whereas 8-OHdG and PSA were positively associated (r= 0.57 (p < 0.002). These results indicate a significant role of oxidative damage in prostate carcinogenesis, particularly during the early stages of development. In conclusion, our data support the importance of antioxidant defense as a valuable diagnostic and/or prognostic marker in prostate cancer.

Variability in Prices for Erectile Dysfunction Medications-Are All Pharmacies the Same?

BACKGROUND

Variability in prices of medications is a well-known phenomenon; however, this variability has not been quantified in the realm of erectile dysfunction (ED) medications. ED medications are ideal for this quantification, because they are often not covered by insurances; therefore, the cost is the most direct reflection of price variability among pharmacies as they affect the patients.

AIM

To evaluate the variability in cash prices for phosphodiesterase type 5 inhibitors (PDEIs) for ED. We also evaluated whether certain types of pharmacies consistently offer better pricing than others, and whether there was any correlation with demographic factors.

METHODS

331 pharmacies were contacted within a 25-mile radius of our institution to obtain the cash price for 4 commonly used ED medications with prespecified doses. After exclusion, 323 pharmacies were categorized as chain, independent, wholesale, or hospital-associated. Cash prices for the specified medications were evaluated. In addition, we identified demographic and socioeconomic factors to determine if these had an impact on median drug pricing within each zip code.

MAIN OUTCOME MEASURE

The main outcome was the cost for patients to fill each prescription.

RESULTS

Independent pharmacies provided the lowest cost for 3 of 4 of the PDEIs. The largest price difference for 10 tablets of 100 mg sildenafil between all pharmacies was 38,000%. The median cost difference between independent pharmacies and chain pharmacies for sildenafil was >900%, and >1,100% for independent pharmacies vs hospital-associated pharmacies. Demographic and socioeconomic factors had no impact on the cost.

CLINICAL IMPLICATIONS

Our goal is to promote patient counseling among practitioners and to empower patients to shop for the best prices for their medications.

STRENGTH AND LIMITATIONS

A strength of the study is the large cohort that was surveyed; however, a weakness is that the large majority of the cohort was comprised of chain pharmacies. Mail pharmacies could not be evaluated as they required a valid prescription before offering prices.

CONCLUSION

The drastic differences in cash prices for the PDEIs give us an insight into the variability and cost-inflation of medications in the United States. These patterns hold true for other essential medications as well, and improved transparency will allow patients to make informed decisions when choosing where to purchase their medications. It may also encourage certain pharmacies to provide medications at more affordable prices. Mishra K, Bukavina L, Mahran A, et al. Variability in prices for erectile dysfunction medications-Are all pharmacies the same? J Sex Med 2018;15:1785-1791.

MR Fingerprinting and ADC Mapping for Characterization of Lesions in the Transition Zone of the Prostate Gland

BackgroundPreliminary studies have shown that MR fingerprinting-based relaxometry combined with apparent diffusion coefficient (ADC) mapping can be used to differentiate normal peripheral zone from prostate cancer and prostatitis. The utility of relaxometry and ADC mapping for the transition zone (TZ) is unknown.PurposeTo evaluate the utility of MR fingerprinting combined with ADC mapping for characterizing TZ lesions.Materials and MethodsTZ lesions that were suspicious for cancer in men who underwent MRI with T2-weighted imaging and ADC mapping (b values, 50-1400 sec/mm2), MR fingerprinting with steady-state free precession, and targeted biopsy (60 in-gantry and 15 cognitive targeting) between September 2014 and August 2018 in a single university hospital were retrospectively analyzed. Two radiologists blinded to Prostate Imaging Reporting and Data System (PI-RADS) scores and pathologic diagnosis drew regions of interest on cancer-suspicious lesions and contralateral visually normal TZs (NTZs) on MR fingerprinting and ADC maps. Linear mixed models compared two-reader means of T1, T2, and ADC. Generalized estimating equations logistic regression analysis was used to evaluate both MR fingerprinting and ADC in differentiating NTZ, cancers and noncancers, clinically significant (Gleason score ≥ 7) cancers from clinically insignificant lesions (noncancers and Gleason 6 cancers), and characterizing PI-RADS version 2 category 3 lesions.ResultsIn 67 men (mean age, 66 years ± 8 [standard deviation]) with 75 lesions, targeted biopsy revealed 37 cancers (six PI-RADS category 3 cancers and 31 PI-RADS category 4 or 5 cancers) and 38 noncancers (31 PI-RADS category 3 lesions and seven PI-RADS category 4 or 5 lesions). The T1, T2, and ADC of NTZ (1800 msec ± 150, 65 msec ± 22, and [1.13 ± 0.19] × 10-3 mm2/sec, respectively) were higher than those in cancers (1450 msec ± 110, 36 msec ± 11, and [0.57 ± 0.13] × 10-3 mm2/sec, respectively; P < .001 for all). The T1, T2, and ADC in cancers were lower than those in noncancers (1620 msec ± 120, 47 msec ± 16, and [0.82 ± 0.13] × 10-3 mm2/sec, respectively; P = .001 for T1 and ADC and P = .03 for T2). The area under the receiver operating characteristic curve (AUC) for T1 plus ADC was 0.94 for separation. T1 and ADC in clinically significant cancers (1440 msec ± 140 and [0.58 ± 0.14] × 10-3 mm2/sec, respectively) were lower than those in clinically insignificant lesions (1580 msec ± 120 and [0.75 ± 0.17] × 10-3 mm2/sec, respectively; P = .001 for all). The AUC for T1 plus ADC was 0.81 for separation. Within PI-RADS category 3 lesions, T1 and ADC of cancers (1430 msec ± 220 and [0.60 ± 0.17] × 10-3 mm2/sec, respectively) were lower than those of noncancers (1630 msec ± 120 and [0.81 ± 0.13] × 10-3 mm2/sec, respectively; P = .006 for T1 and P = .004 for ADC). The AUC for T1 was 0.79 for differentiating category 3 lesions.ConclusionMR fingerprinting-based relaxometry combined with apparent diffusion coefficient mapping may improve transition zone lesion characterization.© RSNA, 2019Online supplemental material is available for this article.

Targeted Biopsy Validation of Peripheral Zone Prostate Cancer Characterization With Magnetic Resonance Fingerprinting and Diffusion Mapping

OBJECTIVE

This study aims for targeted biopsy validation of magnetic resonance fingerprinting (MRF) and diffusion mapping for characterizing peripheral zone (PZ) prostate cancer and noncancers.

MATERIALS AND METHODS

One hundred four PZ lesions in 85 patients who underwent magnetic resonance imaging were retrospectively analyzed with apparent diffusion coefficient (ADC) mapping, MRF, and targeted biopsy (cognitive or in-gantry). A radiologist blinded to pathology drew regions of interest on targeted lesions and visually normal peripheral zone on MRF and ADC maps. Mean T1, T2, and ADC were analyzed using linear mixed models. Generalized estimating equations logistic regression analyses were used to evaluate T1 and T2 relaxometry combined with ADC in differentiating pathologic groups.

RESULTS

Targeted biopsy revealed 63 cancers (low-grade cancer/Gleason score 6 = 10, clinically significant cancer/Gleason score ≥7 = 53), 15 prostatitis, and 26 negative biopsies. Prostate cancer T1, T2, and ADC (mean ± SD, 1660 ± 270 milliseconds, 56 ± 20 milliseconds, 0.70 × 10 ± 0.24 × 10 mm/s) were significantly lower than prostatitis (mean ± SD, 1730 ± 350 milliseconds, 77 ± 36 milliseconds, 1.00 × 10 ± 0.30 × 10 mm/s) and negative biopsies (mean ± SD, 1810 ± 250 milliseconds, 71 ± 37 milliseconds, 1.00 × 10 ± 0.33 × 10 mm/s). For cancer versus prostatitis, ADC was sensitive and T2 specific with comparable area under curve (AUC; (AUCT2 = 0.71, AUCADC = 0.79, difference between AUCs not significant P = 0.37). T1 + ADC (AUCT1 + ADC = 0.83) provided the best separation between cancer and negative biopsies. Low-grade cancer T2 and ADC (mean ± SD, 75 ± 29 milliseconds, 0.96 × 10 ± 0.34 × 10 mm/s) were significantly higher than clinically significant cancers (mean ± SD, 52 ± 16 milliseconds, 0.65 ± 0.18 × 10 mm/s), and T2 + ADC (AUCT2 + ADC = 0.91) provided the best separation.

CONCLUSIONS

T1 and T2 relaxometry combined with ADC mapping may be useful for quantitative characterization of prostate cancer grades and differentiating cancer from noncancers for PZ lesions seen on T2-weighted images.

Younger Men With Prostate Cancer Have Lower Risk of Upgrading While on Active Surveillance: A Meta-analysis and Systematic Review of the Literature

Active surveillance has become a popular option for patients with low risk prostate cancer. Our objective was to examine the correlation between age and the risk of Gleason upgrading and biopsy progression. A systematic search was conducted. Eight studies met our eligibility criteria including 6522 patients with a median age of 65.8 (41-86) years. Per decade decrease in age, the pooled odds ratio and hazard ratio (CI 95%) for Gleason upgrading were 0.83 (0.73-0.94) and 0.87 (0.82-0.92), and for biopsy progression were 0.80 (0.74-0.86) and 0.88 (0.79-0.99), respectively. Overall, younger patients have a lower risk of GS upgrading and biopsy progression.

Patient Reported Outcomes in NRG Oncology RTOG 0938, Evaluating Two Ultrahypofractionated Regimens for Prostate Cancer

PURPOSE

There is considerable interest in very short (ultrahypofractionated) radiation therapy regimens to treat prostate cancer based on potential radiobiological advantages, patient convenience, and resource allocation benefits. Our objective is to demonstrate that detectable changes in health-related quality of life measured by the bowel and urinary domains of the Expanded Prostate Cancer Index Composite (EPIC-50) were not substantially worse than baseline scores.

METHODS AND MATERIALS

NRG Oncology's RTOG 0938 is a nonblinded randomized phase 2 study of National Comprehensive Cancer Network low-risk prostate cancer in which each arm is compared with a historical control. Patients were randomized to 5 fractions (7.25 Gy in 2 weeks) or 12 fractions (4.3 Gy in 2.5 weeks). The co-primary endpoints were the proportion of patients with a change in EPIC-50 bowel score at 1 year (baseline to 1 year) >5 points and in EPIC-50 urinary score >2 points tested with a 1-sample binomial test.

RESULTS

The study enrolled 127 patients to 5 fractions (121 analyzed) and 128 patients to 12 fractions (125 analyzed). Median follow-up for all patients at the time of analysis was 3.8 years. The 1-year frequency for >5 point change in bowel score were 29.8% (P < .001) and 28.4% (P < .001) for 5 and 12 fractions, respectively. The 1-year frequencies for >2 point change in urinary score were 45.7% (P < .001) and 42.2% (P < .001) for 5 and 12 fractions, respectively. For 5 fractions, 32.9% of patients had a drop in 1-year EPIC-50 sexual score of ≥11 points (P = .34); for 12 fractions, 30.9% of patients had a drop in 1-year EPIC-50 sexual score of ≥ 11 points (P = .20). Disease-free survival at 2 years is 99.2% (95% confidence interval: 97.5-100) in the 5-fraction arm and 97.5% (95% confidence interval: 94.6-100) in the 12-fraction arm. There was no late grade 4 or 5 treatment-related urinary or bowel toxicity.

CONCLUSIONS

This study confirms that, based on changes in bowel and urinary domains and toxicity (acute and late), the 5- and 12-fraction regimens are well tolerated. These ultrahypofractionated approaches need to be compared with current standard radiation therapy regimens.

Comparative analysis for renal stereotactic body radiotherapy using Cyberknife, VMAT and proton therapy based treatment planning

PURPOSE

We conducted this dosimetric analysis to evaluate the feasibility of a multi-center stereotactic body radiation therapy (SBRT) trial for renal cell carcinoma (RCC) using different SBRT platforms.

MATERIALS/METHODS

The computed tomography (CT) simulation images of 10 patients with unilateral RCC previously treated on a Phase 1 trial at Institution 1 were anonymized and shared with Institution 2 after IRB approval. Treatment planning was generated through five different platforms aiming a total dose of 48 Gy in three fractions. These platforms included: Cyberknife and volumetric modulated arc therapy (VMAT) at institution 1, and Cyberknife, VMAT, and pencil beam scanning (PBS) Proton Therapy at institution 2. Dose constraints were based on the Phase 1 approved trial.

RESULTS

Compared to Cyberknife, VMAT and PBS plans provided overall an equivalent or superior coverage to the target volume, while limiting dose to the remaining kidney, contralateral kidney, liver, spinal cord, and bowel.

CONCLUSION

This dosimetric study supports the feasibility of a multi-center trial for renal SBRT using PBS, VMAT and Cyberknife.

Absorbable Hydrogel Spacer Use in Prostate Radiotherapy: A Comprehensive Review of Phase 3 Clinical Trial Published Data

OBJECTIVE

To provide an update on SpaceOAR System, a Food and Drug Administration-approved hydrogel indicated to create distance between the prostate and the rectum which has been studied in phase 2 and 3 clinical trials. Here, we review and summarize these clinical results including the safety of prostate-rectum spacer application technique, the implant quality and resulting rectal dose reduction, acute and long-term rectal, urinary, and sexual toxicity, as well as patient-reported outcomes.

MATERIALS AND METHODS

A prospective, randomized patient-blinded clinical study was performed comparing image-guided intensity modulated prostate radiotherapy (79.2 Gy in 44 fractions) in men with or without prostate-rectum hydrogel spacer. Patients were followed up for 3 years, allowing assessment of long-term safety and efficacy.

RESULTS

Spacer application was well tolerated with a 99% technical success rate. The mean additional space created between the prostate and the rectum was just over 1 cm, which allowed significant rectum and penile bulb radiation dose reduction, resulting in less acute pain, lower rates of late rectal toxicity, and improved bowel and urinary quality of life (QOL) scores from 6 months onward. Improvements in sexual QOL were also observed at 37 months in baseline-potent men, with 37.5% of control and 66.7% of spacer men capable of "erections sufficient for intercourse."

CONCLUSION

Prostate-rectum hydrogel spacer application is a relatively safe technical procedure that is well tolerated and has a high technical success rate. Spacer application significantly reduces rectal radiation dose and results in long-term reductions in rectal toxicity, as well as improvements in bowel, urinary, and sexual QOL.

Cost-effectiveness of MR Imaging-guided Strategies for Detection of Prostate Cancer in Biopsy-Naive Men

Purpose To evaluate the cost-effectiveness of multiparametric diagnostic magnetic resonance (MR) imaging examination followed by MR imaging-guided biopsy strategies in the detection of prostate cancer in biopsy-naive men presenting with clinical suspicion of cancer for the first time. Materials and Methods A decision-analysis model was created for biopsy-naive men who had been recommended for prostate biopsy on the basis of abnormal digital rectal examination results or elevated prostate-specific antigen levels (age groups: 41-50 years, 51-60 years, and 61-70 years). The following three major strategies were evaluated: (a) standard transrectal ultrasonography (US)-guided biopsy; (b) diagnostic MR imaging followed by MR imaging-targeted biopsy, with no biopsy performed if MR imaging findings were negative; and (c) diagnostic MR imaging followed by MR imaging-targeted biopsy, with a standard biopsy performed when MR imaging findings were negative. The following three MR imaging-guided biopsy strategies were further evaluated in each MR imaging category: (a) biopsy with cognitive guidance, (b) biopsy with MR imaging/US fusion guidance, and (c) in-gantry MR imaging-guided biopsy. Model parameters were derived from the literature. The primary outcome measure was net health benefit (NHB), which was measured as quality-adjusted life-years (QALYs) gained or lost by investing resources in a new strategy compared with a standard strategy at a willingness-to-pay (WTP) threshold of $50 000 per QALY gained. Probabilistic sensitivity analysis was performed by using Monte Carlo simulations. Results Noncontrast MR imaging followed by cognitively guided MR biopsy (no standard biopsy if MR imaging findings were negative) was the most cost-effective approach, yielding an additional NHB of 0.198 QALY compared with the standard biopsy approach. Noncontrast MR imaging followed by in-gantry MR imaging-guided biopsy (no standard biopsy if MR imaging findings were negative) led to the highest NHB gain of 0.251 additional QALY compared with the standard biopsy strategy. All MR imaging strategies were cost-effective in 94.05% of Monte Carlo simulations. Analysis by age groups yielded similar results. Conclusion MR imaging-guided strategies for the detection of prostate cancer were cost-effective compared with the standard biopsy strategy in a decision-analysis model. ^© RSNA, 2017 Online supplemental material is available for this article.

Development of a Combined MR Fingerprinting and Diffusion Examination for Prostate Cancer

Purpose To develop and evaluate an examination consisting of magnetic resonance (MR) fingerprinting-based T1, T2, and standard apparent diffusion coefficient (ADC) mapping for multiparametric characterization of prostate disease. Materials and Methods This institutional review board-approved, HIPAA-compliant retrospective study of prospectively collected data included 140 patients suspected of having prostate cancer. T1 and T2 mapping was performed with fast imaging with steady-state precession-based MR fingerprinting with ADC mapping. Regions of interest were drawn by two independent readers in peripheral zone lesions and normal-appearing peripheral zone (NPZ) tissue identified on clinical images. T1, T2, and ADC were recorded for each region. Histopathologic correlation was based on systematic transrectal biopsy or cognitively targeted biopsy results, if available. Generalized estimating equations logistic regression was used to assess T1, T2, and ADC in the differentiation of (a) cancer versus NPZ, (b) cancer versus prostatitis, (c) prostatitis versus NPZ, and (d) high- or intermediate-grade tumors versus low-grade tumors. Analysis was performed for all lesions and repeated in a targeted biopsy subset. Discriminating ability was evaluated by using the area under the receiver operating characteristic curve (AUC). Results In this study, 109 lesions were analyzed, including 39 with cognitively targeted sampling. T1, T2, and ADC from cancer (mean, 1628 msec ± 344, 73 msec ± 27, and 0.773 × 10^-3 mm²/sec ± 0.331, respectively) were significantly lower than those from NPZ (mean, 2247 msec ± 450, 169 msec ± 61, and 1.711 × 10^-3 mm²/sec ± 0.269) (P < .0001 for each) and together produced the best separation between these groups (AUC = 0.99). ADC and T2 together produced the highest AUC of 0.83 for separating high- or intermediate-grade tumors from low-grade cancers. T1, T2, and ADC in prostatitis (mean, 1707 msec ± 377, 79 msec ± 37, and 0.911 × 10^-3 mm²/sec ± 0.239) were significantly lower than those in NPZ (P < .0005 for each). Interreader agreement was excellent, with an intraclass correlation coefficient greater than 0.75 for both T1 and T2 measurements. Conclusion This study describes the development of a rapid MR fingerprinting- and diffusion-based examination for quantitative characterization of prostatic tissue. ^© RSNA, 2017 Online supplemental material is available for this article.

Real-time in vivo dosimetry for SBRT prostate treatment using plastic scintillating dosimetry embedded in a rectal balloon: a case study

A novel FDA approved in vivo dosimetry device system using plastic scintillating detectors placed in an endorectal balloon to provide real‐time in vivo dosimetry for prostatic rectal interface was tested for use with stereotactic body radiotherapy (SBRT). The system was used for the first time ever to measure dose during linear accelerator based SBRT. A single patient was treated with a total dose of 36.25 Gy given in 5 fractions. Delivered dose was measured for each treatment with the detectors placed against the anterior rectal wall near the prostate rectal interface. Measured doses showed varying degrees of agreement with computed/ planned doses, with average combined dose found to be within 6% of the expected dose. The variance between measurements is most likely due to uncertainty of the detector location, as well as variation in the placement of a new balloon prior to each fraction. Distance to agreement for the detectors was generally found to be within a few millimeters, which also suggested that the differences in measured and calculated doses were due to positional uncertainty of the detectors during the SBRT, which had sharp dose falloff near the penumbra along the rectal wall. Overall, the use of a real time in vivo dosimeter provided a level of safety and improved confidence in treatment delivery. We are evaluating the device further in an IRB‐approved prospective partial prostate SBRT trial, and believe further clinical investigations are warranted.

PACS number(s): 87.53.Bn, 87.53.Ly, 87.55.km

Outcomes and toxicities in patients treated with definitive focal therapy for primary prostate cancer: systematic review

AIM

This systematic review summarizes the clinical data on focal therapy (FT) when used alone as definitive therapy for primary prostate cancer (PCa).

METHODS

The protocol is detailed in the online PROSPERO database, registration No. CRD42014014765. Articles evaluating any form of FT alone as a definitive treatment for PCa in adult male patients were included.

RESULTS

Of 10,419 identified articles, 10,401 were excluded, and thus leaving 18 for analysis. In total, 2288 patients were treated using seven modalities. The outcomes of FT in PCa seem to be similar to those observed with whole gland therapy and with fewer side effects.

CONCLUSION

Further research, including prospective randomized trials, is warranted to elucidate the potential advantages of focal radiation techniques for treating PCa. Prospero Registration Number: CRD42014014765.

Does gender influence morbidity or mortality in the surgical treatment of renal masses?

INTRODUCTION

We determine the relationship between gender and surgical morbidity after radical nephrectomy (RN) and partial nephrectomy (PN) for renal masses on a population level.

METHODS

We conducted a population-based, retrospective study using the Canadian Institute for Health Information Discharge Abstract Database. This included 20 286 RNs (82.5%) and 4292 PNs (17.5%) from April 1, 1998 to March 31, 2008. Complications were identified by ICD-9 and 10 codes, and comorbidity was assessed with the Charlson Index. The association between gender and in-hospital complication rates and mortality were examined using the Chi-square test, as well as with multivariable logistic regression, adjusting for explanatory variables including type of surgery, age, and comorbidity.

RESULTS

Overall, men experienced a higher unadjusted complication rate than women (35.1% vs. 32.7%), as well as a higher unadjusted in-hospital mortality rate (1.46% vs. 0.84%), respectively. Men also demonstrated significantly higher rates of cardiac, wound, nephrectomy-specific, and medical complications. Women experienced fewer complications than men after RN (p = 0.0002), but not after PN (p = 0.33). On multivariable logistic regression analysis, women had a lower overall complication rate (odds ratio [OR] 0.94, 95% confidence interval [CI] 0.88-0.99), and a lower inhospital mortality rate (OR 0.64, 95% CI 0.49-0.83) after kidney surgery.

CONCLUSIONS

In our population-based analysis, in-hospital morbidity after renal surgery was significantly lower for women. Further study is needed to determine if the observed effect is related to differences in surgical difficulty, perioperative care, or unmeasured confounders.

Abstract 9: Oxidative stress and antioxidant status in high-risk prostate cancer subjects

Prostate cancer is the most commonly diagnosed cancer among men in the United States. Epidemiological, experimental and clinical studies have implicated chronic inflammation and oxidative stress in the development and progression of prostate cancer. Diet, environmental carcinogens, aging, and other inflammatory diseases cause aberration in reactive oxygen species (ROS) which may play critical roles in the development and progression of prostate cancer. Chronic inflammation results in lipid peroxidation and generation of highly reactive products with the potential to damage DNA. The extent of ROS-induced oxidative damage can be determined by measuring reductions in levels of endogenous antioxidant defense enzymes such as glutathione-s-transferase (GST), glutathione peroxidase (GSH-Px), glutathione reductase (GSH-R), catalase (CAT), superoxide dismutase (SOD) and non-protein thiols, which participate in detoxification processes. The aim of this study was to assess the oxidative status and antioxidant defense mechanisms in 20 men, 54-84 years of age, with increased risk of developing prostate cancer because of the presence of high-grade prostatic intraepithelial neoplasia (HGPIN) in their prostate biopsies, as compared to 20 healthy men in the same age range whose prostate biopsies showed no evidence of HGPIN. Total glutathione levels were measured in red blood cells, and plasma levels of GSH-Px, GSH-R, CAT, SOD, and PSA were analyzed. Data obtained after analysis was represented as mean, standard error and box plot. Serum PSA levels were significantly (p&lt;0.0001) higher in men with HGPIN, whereas glutathione (P=0.002) levels were higher in men without HGPIN. Levels of 8-hydroxydeoxyguanosine (8-OHdG), an oxidized nucleoside of DNA that is most often detected in the DNA of white blood cells, were significantly (p&lt;0.00001) increased in men with HGPIN. There was no significant difference in levels of GSH-R, GSH-Px, lipid peroxide products, CAT, and SOD in men with or without HGPIN. A significant association in between CAT and GSH-Px activity [r= -0.33 (P=0.04)]; PSA levels and 8-OHdG [r= 0.57 (P=0.002] and between glutathione and 8-OHdG [r= -0.39 (P=0.038] were noted between men with HGPIN and healthy controls using Pearson correlation coefficient. These findings indicate that oxidative stress induces imbalances in oxidant/antioxidant status. Increased 8-OHdG levels may lead to oxidative damage and may thereby play an important role in the development of prostate cancer.

Citation Format: Sanjeev Shukla, Janmejai K. Srivastava, Rajnee Kanwal, Akbar Nawab, Haripaul Sharma, Natarajan Bhaskaran, Claudia Lillibridge, Lee E. Ponsky, Pingfu Fu, Gregory T. MacLennan, Sanjay Gupta. Oxidative stress and antioxidant status in high-risk prostate cancer subjects. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 9. doi:10.1158/1538-7445.AM2013-9

Pneumodissection: an alternative protective technique for the percutaneous cryoablation of small renal masses

INTRODUCTION

Percutaneous cryoablation is an emerging treatment option for the small renal mass. It poses a risk of thermal injury to adjacent tissues, limiting its application. We describe pneumodissection, a novel technique for preventing thermal injury during percutaneous cryoablation.

MATERIALS AND METHODS

The cases of 4 patients who underwent percutaneous renal cryoablation and pneumodissection were retrospectively reviewed.

RESULTS

Pneumodissection mechanically separated four tumors from overlying bowel segments (mean distance 1.2 ± 0.4 cm), permitting successful cryoablation. There were no complications or recurrences with 7.5 months of follow-up.

CONCLUSIONS

Pneumodissection is a feasible displacement technique that facilitates percutaneous cryoablation in at-risk patients. Further study is warranted.

Protection against oxidative DNA damage and stress in human prostate by glutathione S-transferase P1

The pi-class glutathione S-transferase (GSTP1) actively protect cells from carcinogens and electrophilic compounds. Loss of GSTP1 expression via promoter hypermethylation is the most common epigenetic alteration observed in human prostate cancer. Silencing of GSTP1 can increase generation of reactive oxygen species (ROS) and DNA damage in cells. In this study we investigated whether loss of GSTP1 contributes to increased DNA damage that may predispose men to a higher risk of prostate cancer. We found significantly elevated (103%; P < 0.0001) levels of 8-oxo-2'-deoxogunosine (8-OHdG), an oxidative DNA damage marker, in adenocarcinomas, compared to benign counterparts, which positively correlated (r = 0.2) with loss of GSTP1 activity (34%; P < 0.0001). Silencing of GSTP1 using siRNA approach in normal human prostate epithelial RWPE1 cells caused increased intracellular production of ROS and higher susceptibility of cells to H2 O2 -mediated oxidative stress. Additionally, human prostate carcinoma LNCaP cells, which contain a silenced GSTP1 gene, were genetically modified to constitutively express high levels of GSTP1. Induction of GSTP1 activity lowered endogenous ROS levels in LNCaP-pLPCX-GSTP1 cells, and when exposed to H2 O2 , these cells exhibited significantly reduced production of ROS and 8-OHdG levels, compared to vector control LNCaP-pLPCX cells. Furthermore, exposure of LNCaP cells to green tea polyphenols caused reexpression of GSTP1, which protected the cells from H2 O2 -mediated DNA damage through decreased ROS production compared to nonexposed cells. These results suggest that loss of GSTP1 expression in human prostate cells, a process that increases their susceptibility to oxidative stress-induced DNA damage, may be an important target for primary prevention of prostate cancer.

Endoscopic snare resection of bladder tumors: evaluation of an alternative technique for bladder tumor resection

Transurethral resection of bladder tumor (TURBT) is the standard of care for initial bladder tumor management. In response to its shortcomings, we propose an alternative technique for tumor resection and retrieval: The endoscopic snare resection of bladder tumor (ESRBT). Eleven tumors managed by ESRBT were reviewed retrospectively. Via cystoscopy, tumors were resected en bloc with an electrosurgical polypectomy snare and retrieved transurethrally. Safety and efficacy were assessed by clinical and pathologic outcomes. ESRBT was highly effective for appropriate tumors. Tumor size and location varied: Two small, six medium, three large; six lateral wall, two dome, two trigone, one posterior wall. Half of initial urothelial carcinoma specimens contained muscle. There were no intraoperative or postoperative complications (mean follow-up: 17 mos; range 10-25 mos). ESRBT is a feasible technique for the resection of pedunculated bladder tumors. It offers evident and theoretical advantages over TURBT and may augment bladder tumor management. Further study is needed.

Abstract 2569: Lyc-O-Mato causes cell cycle arrest and apoptosis in human bladder transitional carcinoma cells

Approximately two thirds of new bladder cancer cases in the United States are superficial papillary transitional cell carcinoma (TCC), the majority of which are low-grade neoplasms. Data suggest that bladder carcinogenesis is a multi-step, multi-focal (field effect) process, possibly involving the spread of pre-malignant clones-all of which are prerequisites for effective preventive and/or interventional approaches. Epidemiological data suggests an inverse relationship between serum levels of carotenoids and risk of bladder cancer which has encouraged further investigation. In this study, we evaluated the effect of Lyc-O-Mato® (a crude tomato extract containing 10% lycopene and other tomato phytonutrients viz. tocopherols, phytoene, phytofluene, beta-carotene, phospholipids and phytosterols) on human bladder cancer cell growth, cell cycle modulation, induction of apoptosis, and associated molecular alterations. Treatment of bladder cancer cell lines (T-24, high-grade TCC and TCC-SUP, high-grade invasive tumor) with Lyc-O-Mato® at doses of 1-60µM resulted in inhibition of cell growth along with a G1 arrest in T24 cells and G2/M arrest in TCCSUP cells at 24 h post-treatment. In other studies, Lyc-O-Mato® treatment strongly induced the expression of p21/waf1 and p27/kip1, and resulted in a decrease in cyclin-dependent kinases (CDKs) and cyclins involved in G1 and G2/M progression in T24 and TCC SUP cells. Lyc-O-Mato® exposure to these cells showed an increased interaction between cyclin dependent kinase inhibitors (CDKIs)-cyclin-dependent kinases (CDKs) and decrease in the interaction of cyclins and CDKs with their respective stages of the cell cycle. Furthermore, Lyc-O-Mato® treatment significantly reduced the phosphorylation of Retinoblastoma at Serine780, although no significant changes were observed in the total levels of this protein. In additional studies, Lyc-O-Mato® showed a dose- and time-dependent apoptotic death in both T24 and TCC SUP cells which was associated with significant downregulation of survivin along with the enhancement of pro-apoptotic protein, Bax. These observations provide a strong rationale for further evaluating preventive and/or intervention strategies for Lyc-O-Mato® in pre-clinical models of bladder cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2569. doi:1538-7445.AM2012-2569

Contrast-induced nephropathy and nephrogenic systemic fibrosis: minimizing the risk

INTRODUCTION

Contrast-enhanced cross-sectional imaging is essential to the urologist's practice. Traditionally, patients with impaired renal function could not be imaged with a computed tomography (CT) scan with contrast due to the risk of contrast-induced nephropathy (CIN). These patients could alternatively be imaged by magnetic resonance imaging (MRI) with gadolinium. However, the recent identification of the association between nephrogenic systemic fibrosis (NSF) and gadolinium administration has created significant challenges for urologists and radiologists when faced with the need for evaluation with contrast-enhanced cross-sectional imaging. In this review, we summarize the most comprehensive articles discussing both NSF and CIN and present a straightforward, evidence-based algorithm to determine the appropriate approach to cross-sectional imaging for all patients, as well as future directions regarding cross-sectional imaging.

MATERIALS AND METHODS

A MEDLINE literature search for review articles from 1966 to August 2009 was performed. Selected additional articles for specific topics were also reviewed. This search yielded a total of 25 articles for NSF and 28 for CIN that were reviewed.

RESULTS

The pathophysiology and risk factors of NSF and CIN are discussed, as well as potential interventions to decrease either morbidity or incidence. A multidisciplinary (urologist, nephrologist, radiologist) evidence-based algorithm is introduced for managing patients in need of cross-sectional imaging.

CONCLUSIONS

The associated risks of contrast-enhanced, cross-sectional imaging has created significant challenges for urologic evaluation. We propose an evidence-based approach to guide patient therapy, which can minimize patient risk and physician anxiety, while simplifying the decision-making process.

Molecular imaging of nuclear factor-κB in bladder as a primary regulator of inflammatory response

PURPOSE

Nuclear factor-κB activation is implicated in chronic inflammatory disorders and it is a key regulator of genes involved in the response to infection, inflammation and stress. Interstitial cystitis and painful bladder syndrome are common inflammatory disorders of the bladder characterized by frequent urination and bladder pain. The role of nuclear factor-κB activation in bladder inflammation is not well defined.

MATERIALS AND METHODS

Female transgenic nuclear factor-κB-luciferase Tag mice (The Jackson Laboratory, Bar Harbor, Maine) were used to perform serial, noninvasive in vivo and ex vivo molecular imaging of nuclear factor-κB activation in the whole body after administering arsenic trioxide (5 mg/kg), lipopolysaccharide (2 mg/kg) or cyclophosphamide (Sigma®) (200 mg/kg) to initiate acute transient bladder inflammation. Pretreatment with dexamethasone (Sigma) (10 mg/kg) was used to modulate cyclophosphamide induced nuclear factor-κB dependent luminescence in vivo.

RESULTS

Treatment of nuclear factor-κB-luciferase Tag mice with chemicals increased luminescence in a time and organ specific manner in vivo and ex vivo. The highest levels of bladder nuclear factor-κB dependent luminescence were observed 4 hours after cyclophosphamide administration. Pretreatment with dexamethasone 1 hour before cyclophosphamide injection significantly down-regulated cyclophosphamide induced bladder nuclear factor-κB dependent luminescence, ameliorated the grossly evident pathological features of acute inflammation and decreased cellular immunostaining for nuclear factor-κB in the bladder.

CONCLUSIONS

Nuclear factor-κB activity may have an important role in the pathophysiology of bladder inflammation. Nuclear factor-κB-luciferase mice can serve as a useful model in which to screen potential candidate drugs for cystitis associated with aberrant nuclear factor-κB activity. Such screening may significantly aid the development of therapeutic strategies to manage inflammatory bladder disorders.

Technical and equipment challenges for laparoendoscopic single-site surgery and natural orifice transluminal endoscopic surgery

Laparoendoscopic single-site surgery (LESS) and natural orifice transluminal endoscopic surgery (NOTES™) are new approaches to minimally invasive surgery. A number of technical challenges need to be overcome and new developments of equipment are required before widespread acceptance of either modality occurs. In this paper we discuss novel approaches and innovations as well as review examples of equipment and platforms that have previously been used for LESS and NOTES. Emphasis is given to urological applications.

Extracorporeal stereotactic radiosurgery for small renal masses

Over the past decade we have witnessed both a grade and stage migration for renal cell carcinoma. This shift in clinicopathology has been met with a paradigm shift in the treatment of these renal mass lesions. This trend has evolved from laparoscopic extirpation to needle-based and now extracorporeal ablation. At the forefront of the extracorporeal, minimally invasive treatment modalities is radiosurgical ablation. Still in its inaugural phase, renal radiosurgery is devoid of any long-term studies; however, short-term studies thus far show enormous potential. Herein we present the current status of radiosurgical ablation of small renal masses.

Prospective evaluation of prostate cancer risk in candidates for inguinal hernia repair

BACKGROUND

Preperitoneal placement of mesh during herniorraphy has been shown to complicate future extirpative prostate surgery. We investigated the value of a prostate cancer screening program in patients considering laparoscopic inguinal herniorrhaphy to identify men at risk of prostate cancer.

STUDY DESIGN

A prospective cohort study was conducted in men 30 years of age or older presenting with inguinal hernia. All patients were counseled on prostate cancer risk and the potential for herniorrhaphy with mesh placement to complicate future pelvic surgery. Serum prostate specific antigen (PSA) values were obtained, and patients determined to be at increased relative risk of prostate cancer were referred for urologic evaluation. Transrectal ultrasonography-guided biopsy was performed if clinically indicated, and operative data for patients undergoing prostate cancer treatment were retrospectively reviewed.

RESULTS

There were 1,324 patients who presented for management of inguinal hernia; 814 of these (median age 60 years) consented to screening. Overall, 259 (32%) had an increased relative risk of prostate cancer based on PSA 1.0 to 2.49 ng/mL, and 152 (19%) had PSA > or = 2.5 ng/mL. Transrectal ultrasonography-guided biopsy was performed in 86 patients. Prostate cancer was identified on initial or repeat biopsy in 31 patients (3.8%), including 1 patient (0.7%) younger than 50 years of age.

CONCLUSIONS

We found the incidence of concurrent prostate cancer with hernia to be low, but 51% of men had PSA values that suggested an increased relative risk of future development of prostate cancer. Men at increased risk of prostate cancer should be made aware of the impact that mesh might have on subsequent treatment options before mesh placement.

Pure natural orifice translumenal endoscopic surgery partial cystectomy: intravesical transurethral and extravesical transgastric techniques in a porcine model

OBJECTIVES

To describe 2 pure natural orifice translumenal endoscopic surgery (NOTES) techniques for partial cystectomy in a porcine model. NOTES is a new minimally invasive modality for performing abdominal surgery without transcutaneous incision.

METHODS

Transurethral-A rigid cystoscope is inserted into the porcine bladder with CO(2) insufflation. With an endoscopic loop device and a grasping device, the targeted area of the bladder is manipulated into the loop. The bladder segment is excised with electrocautery. Transgastric-A gastrotomy is made with a dual channel endoscope in the porcine stomach. The endoscope is inserted and pneumoperitoneum is established by insufflation through a channel. After identifying bladder, 2 endoscopic loops are placed at the intended area of resection. An incision is made between the loops to excise the specimen. In both cases, full-thickness specimen is removed en bloc with the scope and the defect is reapproximated with endoscopic clips.

RESULTS

Transurethral and transgastric NOTES approaches were achieved using standard endoscopic equipment in a porcine model. Transurethral NOTES partial cystectomy was successful in acute (n = 2) and chronic (n = 2) models. The transgastric NOTES approach was successfully performed in an acute animal.

CONCLUSIONS

NOTES partial cystectomy could potentially reduce morbidity of conventional methods of partial cystectomy. Transurethral NOTES may be the least invasive method possible for partial cystectomy. Potential advantages of a transgastric NOTES approach include visualization of adjacent structures, access to sites difficult to reach transurethrally, and lymph node sampling. However, a gastrotomy could be a source of morbidity. Further investigation is required to assess safety, efficacy, and adequate bladder healing.

Natural orifice translumenal endoscopic surgery: myth or reality?

Interest in natural orifice translumenal endoscopic surgery (NOTES) has blossomed since the publication of transgastric peritoneoscopy in animals in 2004. Laboratory research has demonstrated the feasibility of natural orifice surgery and provided insight into the technical innovations necessary to advance the field. Today, natural orifice surgery is entering the clinical realm, both in hybrid laparoscopic-endoscopic cases and a few pure natural orifice procedures. Although the promise of "scarless" surgery entices clinicians and the public alike, care must be taken to introduce novel techniques as safely as possible with critical evaluation of outcomes.