Metabolic activity diffusion imaging (MADI): II. Noninvasive, high-resolution human brain mapping of sodium pump flux and cell metrics

We introduce a new ¹ H₂ O magnetic resonance approach: metabolic activity diffusion imaging (MADI). Numerical diffusion-weighted imaging decay simulations characterized by the mean cellular water efflux (unidirectional) rate constant (k_io ), mean cell volume (V), and cell number density (ρ) are produced from Monte Carlo random walks in virtual stochastically sized/shaped cell ensembles. Because of active steady-state trans-membrane water cycling (AWC), k_io reflects the cytolemmal Na⁺ , K⁺ ATPase (NKA) homeostatic cellular metabolic rate (^c MR_NKA ). A digital 3D "library" contains thousands of simulated single diffusion-encoded (SDE) decays. Library entries match well with disparate, animal, and human experimental SDE decays. The V and ρ values are consistent with estimates from pertinent in vitro cytometric and ex vivo histopathological literature: in vivo V and ρ values were previously unavailable. The library allows noniterative pixel-by-pixel experimental SDE decay library matchings that can be used to advantage. They yield proof-of-concept MADI parametric mappings of the awake, resting human brain. These reflect the tissue morphology seen in conventional MRI. While V is larger in gray matter (GM) than in white matter (WM), the reverse is true for ρ. Many brain structures have k_io values too large for current, invasive methods. For example, the median WM k_io is 22s^-1 ; likely reflecting mostly exchange within myelin. The k_io •V product map displays brain tissue ^c MR_NKA variation. The GM activity correlates, quantitatively and qualitatively, with the analogous resting-state brain ¹⁸ FDG-PET tissue glucose consumption rate (^t MR_glucose ) map; but noninvasively, with higher spatial resolution, and no pharmacokinetic requirement. The cortex, thalamus, putamen, and caudate exhibit elevated metabolic activity. MADI accuracy and precision are assessed. The results are contextualized with literature overall homeostatic brain glucose consumption and ATP production/consumption measures. The MADI/PET results suggest different GM and WM metabolic pathways. Preliminary human prostate results are also presented.

SNPs at SMG7 Associated with Time from Biochemical Recurrence to Prostate Cancer Death

BACKGROUND

A previous genome-wide association study identified several loci with genetic variants associated with prostate cancer survival time in two cohorts from Sweden. Whether these variants have an effect in other populations or if their effect is homogenous across the course of disease is unknown.

METHODS

These variants were genotyped in a cohort of 1,298 patients. Samples were linked with age, PSA level, Gleason score, cancer stage at surgery, and times from surgery to biochemical recurrence to death from prostate cancer. SNPs rs2702185 and rs73055188 were tested for association with prostate cancer-specific survival time using a multivariate Cox proportional hazard model. SNP rs2702185 was further tested for association with time to biochemical recurrence and time from biochemical recurrence to death with a multi-state model.

RESULTS

SNP rs2702185 at SMG7 was associated with prostate cancer-specific survival time, specifically the time from biochemical recurrence to prostate cancer death (HR, 2.5; 95% confidence interval, 1.4-4.5; P = 0.0014). Nine variants were in linkage disequilibrium (LD) with rs2702185; one, rs10737246, was found to be most likely to be functional based on LD patterns and overlap with open chromatin. Patterns of open chromatin and correlation with gene expression suggest that this SNP may affect expression of SMG7 in T cells.

CONCLUSIONS

The SNP rs2702185 at the SMG7 locus is associated with time from biochemical recurrence to prostate cancer death, and its LD partner rs10737246 is predicted to be functional.

IMPACT

These results suggest that future association studies of prostate cancer survival should consider various intervals over the course of disease.

Atezolizumab (atezo) with or without Bacille Calmette-Guérin (BCG) in patients (pts) with high-risk nonmuscle-invasive bladder cancer (NMIBC): Results from a phase Ib/II study

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Background: Standard treatment (tx) for high-risk NMIBC is transurethral resection of bladder tumor (TURBT) followed by BCG induction and maintenance. However, ≈50% of pts experience recurrence and/or progression after tx and may be ineligible for or refuse cystectomy. The PD-L1/PD-1 pathway may be involved with immune escape in NMIBC following BCG exposure. Here, we report results of atezo (anti–PD-L1) ± BCG in BCG-unresponsive, high-risk NMIBC. Methods: This multicenter study (NCT02792192) enrolled pts with BCG-unresponsive NMIBC with carcinoma in situ who had repeat TURBT. Cohort 1A and 1B pts received atezo 1200 mg IV q3w for ≤96 wk. Cohort 1B pts also received standard BCG induction (qw × 6 doses) and maintenance (qw × 3 doses at 3 mo), with optional maintenance courses at 6, 12, 18, 24, and 30 mo. For cohort 1B only, de-escalation was allowed for ≤3 BCG dose levels (full dose 50 mg, 66% and 33% of full dose). Co-primary outcomes were safety and complete response (CR) rate at 6 mo (6-mo bladder biopsy required). Duration of CR and 3-mo CR rate (key secondary outcomes) and 12-mo CR rate (exploratory) were also shown. Results: Cohorts 1A and 1B enrolled 12 pts each. Median age was 74 y; most pts had ECOG PS 0 (n = 7 [58%] in each cohort). At data cutoff (Sep 29, 2020), median atezo tx duration was 22.7 wk in cohort 1A and 31.6 wk in 1B. Following dose de-escalation in cohort 1B, the recommended BCG dose was 50 mg. BCG dose modification/interruption occurred in 4 pts (33%) due to an AE. The most common reason for tx discontinuation was disease recurrence or progression in both cohorts. Three pts (25%) in cohort 1A had atezo-related Gr 3 AEs (most common: maculopapular rash, n = 2); no atezo- or BCG-related Gr ≥3 AEs were seen in cohort 1B. Three dose-limiting toxicities occurred (1 [8%] in cohort 1A and 2 [17%] in cohort 1B), all reported as AEs of special interest. No Gr 4/5 AEs were reported. CRs, which appeared durable, were seen in both cohorts (Table). Conclusions: In this first report of atezo + BCG in NMIBC, atezo as mono- and combination therapy was well tolerated, with no new safety signals or tx-related deaths. Preliminary data suggested clinically meaningful activity, especially with atezo + BCG, requiring confirmation in a larger setting. Clinical trial information: NCT02792192. [Table: see text]

Epigenetic loss of heterogeneity from low to high grade localized prostate tumours

Identifying precise molecular subtypes attributable to specific stages of localized prostate cancer has proven difficult due to high levels of heterogeneity. Bulk assays represent a population-average, which mask the heterogeneity that exists at the single-cell level. In this work, we sequence the accessible chromatin regions of 14,424 single-cells from 18 flash-frozen prostate tumours. We observe shared chromatin features among low-grade prostate cancer cells are lost in high-grade tumours. Despite this loss, high-grade tumours exhibit an enrichment for FOXA1, HOXB13 and CDX2 transcription factor binding sites, indicating a shared trans-regulatory programme. We identify two unique genes encoding neuronal adhesion molecules that are highly accessible in high-grade prostate tumours. We show NRXN1 and NLGN1 expression in epithelial, endothelial, immune and neuronal cells in prostate cancer using cyclic immunofluorescence. Our results provide a deeper understanding of the active gene regulatory networks in primary prostate tumours, critical for molecular stratification of the disease.

Survival outcomes and practice trends for off-label use of adjuvant targeted therapy in high-risk locoregional renal cell carcinoma

IMPORTANCE

The appropriate use of adjuvant targeted therapy (TT) for high-risk locoregional renal cell carcinoma (RCC) after nephrectomy is currently unclear due to mixed results from the relevant randomized controlled trials. National-level survival outcomes and practice trends for the use of adjuvant TT in the United States have not been reported.

OBJECTIVE

To compare overall survival for patients who did and did not receive adjuvant TT after nephrectomy for high-risk locoregional RCC.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study reviewed the National Cancer Database from 2006 to 2015. Patients with nonmetastatic clear cell RCC who underwent nephrectomy with either stage pT3a or greater or pN+ were included.

MAIN OUTCOMES AND MEASURES

Adjuvant TT was defined as receipt of TT within 3 months of nephrectomy. The primary end point was overall survival from initial diagnosis to date of death or censored at last follow-up. Baseline characteristics were described, and a multivariable analysis identified associations for receipt of adjuvant TT. Nearest-neighbor propensity matching was performed to create similar groups for comparison. A survival analysis was performed using Kaplan-Meier analysis and log-rank test.

RESULTS

The final study population included 41,127 patients. Two thousand seventy-one patients (5.04%) received off-label adjuvant TT. Younger age, white race, private insurance, positive margins, pT4, and pN+ were associated with receipt of adjuvant TT. After nearest-neighbor propensity matching for clinically and statistically relevant covariates, 1,604 patients remained in the matched cohort, with statistically nonsignificant differences between the groups for all baseline characteristics. Median overall survival was 52 months for patients in the Adjuvant TT group versus 79 months for those who did not receive adjuvant TT (P < 0.001). Decreased overall survival for patients receiving adjuvant therapy was also seen in pathologic subgroups with and without lymph node involvement.

CONCLUSIONS

The propensity matched survival analysis revealed significantly decreased overall survival in patients who received off-label adjuvant TT for high-risk locoregional RCC.

Predictors of positive lesions in 18F-fluciclovine PET/CT

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Background: The 18F-Fluciclovine (FACBC) PET/CT scan has higher sensitivity than traditional imaging modalities for detection of prostate cancer (PCa) recurrence. We aim to identify the PSA characteristics as predictors of positive FACBC scan. Methods: Seventy-eight patients who underwent FACBC scan in 2018 at our institution were identified. Patient demographics, prior PSA, clinical information including prior treatment was recorded. Scans were deemed positive if definitive lesions were noted at the prostate bed, pelvic lymph nodes, or skeletal level. Detection rate was the ratio of positive over total scans and was calculated for PSA ranges. PSA velocity (PSAV) was calculated for patients who did not initiate androgen-deprivation therapy 12 months prior to the scan. The baseline PSA and PSAV were modeled as predictors of having a positive scan using logistic regression. Results: The median baseline PSA is 2.7 (range 0.2 - 226.5). The rates of positivity increased with increasing baseline PSA (Table 1). Positive scans had higher median baseline PSA (3.0, range 0.2-226.5 vs. 1.2, range 0.2-26.0; p = 0.0015) and higher PSAV (median 2.3, range -0.6-1478.7 vs. 1.0, range -0.5-31.9; p = 0.025). Baseline PSA (AUC = 0.712) was better predictor than PSAV (AUC = 0.656) of a positive scan. Combining the two variables does not improve their predictive ability (AUC = 0.719). There is a 50% detection rate in post-radical prostatectomy (RP) patients (Table 2). Conclusions: FACBC PET’s detection rate increases with increasing baseline PSA. While higher PSAV is associated with higher rate of positive scan, it did not increase the predictive ability of baseline PSA for a positive scan in prostate cancer recurrence patients. [Table: see text][Table: see text]

Unconventional Bladder Preservation: Factors Predicting Failure to Receive Definitive Surgery following Chemotherapy for Nonmetastatic Muscle Invasive Bladder Cancer in the National Cancer Database

PURPOSE

Neoadjuvant chemotherapy is an important adjunct to cystectomy for managing muscle invasive bladder cancer. Using the National Cancer Database we investigated factors that predict failure to undergo surgery following multi-agent chemotherapy for nonmetastatic muscle invasive bladder cancer.

MATERIALS AND METHODS

We performed a cohort study in patients diagnosed with cT2-4aN0M0 urothelial cell carcinoma of the bladder between 2004 and 2013 who underwent multi-agent chemotherapy. We excluded those with surgery prior to chemotherapy, clinical T4b disease and those who received radiotherapy. Socioeconomic and clinical predictors, including time from diagnosis to treatment, were analyzed using logistic regression for the receipt of surgery after chemotherapy. Cox proportional hazards modeling was applied to perform time dependent analysis.

RESULTS

Of the 4,640 patients who met our study inclusion and exclusion criteria 4,244 (91%) proceeded to surgery. Negative predictors of surgery included African American or Hispanic race (OR 0.58, p = 0.007 and 0.48, p = 0.002, respectively), increasing age (OR 0.44, p <0.001) and greater time between diagnosis and chemotherapy initiation (fourth quartile greater than 59 days, OR 0.51, p <0.001). African American race (HR 0.79, p <0.001), Medicare (HR 0.86, p <0.001) and other government insurance (HR 0.73, p <0.001) were associated with delayed chemotherapy.

CONCLUSIONS

Increasing age, African American or Hispanic race and longer time to chemotherapy predicted failure to undergo surgery. Furthermore, African American race was associated with delayed chemotherapy. Chemotherapy was also delayed in patients on Medicare or other government insurance. Longer time to neoadjuvant chemotherapy is a modifiable risk factor that should be closely observed in multimodal cancer treatment.

Bilateral Testicular Germ Cell Tumors in the Era of Multimodal Therapy

OBJECTIVE

To characterize the incidence, presentation, management, and relapse of a large population of bilateral testicular germ cell tumors (TGCT) from a single institution.

PATIENTS AND METHODS

We identified bilateral TGCT diagnosed between January 1989 and February 2014. We categorized synchronous and metachronous TGCT, noting time between first and second TGCT, histology (seminoma vs nonseminoma [NSGCT]), stage, and treatments. Kaplan-Meier survival estimates characterized relapse.

RESULTS

Of 5132 patients with TGCT, 128 (2.5%) had bilateral TGCT. Bilateral TGCT increased over time-1.7% in 1989-1994 up to 3.8% in 2010 to February 2014. The 35 (27%) synchronous cases of TGCT had 20 (57%) concordant seminoma, 5 (14%) concordant NSGCT, and 10 (29%) discordant NSGCT. The 93 (73%) metachronous cases had median time interval to second TGCT of 73 months (range: 5 months-28.6 years). Compared with first TGCT, 39 (42%) had discordant histology, 29 (31%) had concordant seminoma, and 25 (27%) had concordant NSGCT. Stage at first tumor was statistically similar to second TGCT (second stage I, II, II in 69%, 22%, 10%). Increasing duration between first and second TGCT was not associated with higher stage (II or III) at second TGCT (P = .09). Treatment at first tumor was not associated with stage at second tumor. Relapse following bilateral diagnosis was 16.8% (95% confidence interval 10.5%-26.2%) at 5 years.

CONCLUSION

Incidence of bilateral TGCT increased with >25% of metachronous TGCT presenting ≥10 years after first TGCT; possible causes include increased survivorship and referral bias. Stage was statistically similar at first and second tumor; stage at second tumor was not associated with time interval between tumors or prior treatment modality at first tumor.

Association of rise in C-reactive protein with decline in renal function following partial nephrectomy

INTRODUCTION

To investigate association of C-reactive protein (CRP), a marker of systemic inflammation, with renal functional decline patients undergoing partial nephrectomy (PN) for renal mass.

MATERIALS AND METHODS

Retrospective study of patients who underwent PN between February 2006-March 2011, with ≥ 6 months follow up. Data was analyzed between two groups: CRP increase ≥ 0.5 mg/L from 6 months postoperative ('CRP rise,' CRPR), versus no CRP increase = 0.5 ('CRP stable,' CRPS). Primary outcome was change in estimated glomerular filtration rate (ΔeGFR, mL/min/1.73 m²), with de novo postoperative stage III chronic kidney disease (stage III-CKD, eGFR < 60 mL/min/1.73 m²) being secondary. Multivariable analysis (MVA) was conducted to identify risk factors for development of de novo stage III-CKD.

RESULTS

A total of 243 patients (206 CRPS/37 CRPR) were analyzed. Demographics and R.E.N.A.L. nephrometry scores were similar. CRPR had significantly higher median ΔeGFR (-13.7 versus -32.0 mL/min/1.73 m², p < 0.001) and de novo stage III-CKD at last follow up (43.2% vs. 3.7%, p < 0.001). Median time to CRP rise was 10 (IQR 6.5-12) months. Median time from CRP rise to de novo stage III-CKD was 9 (IQR 7.5-11) months. MVA found RENAL score (OR 1.89, p = 0.001), hypertension (OR 4.75, p = 0.016), and CRP rise (OR 55.76, p < 0.001) were associated with de novo stage III-CKD. Sensitivity of CRP increase ≥ 0.5 for predicting CKD was 69.6%, specificity 93.3%, positive predictive value 55.2%, and negative predictive value 96.3%.

CONCLUSION

Rise in CRP postoperatively is independently associated with renal functional decline after PN and may be useful in identifying patients to evaluate for renoprotective strategies. Further studies are requisite to clarify etiology of this association.

Impact of renal surgery for cortical neoplasms on lipid metabolism

OBJECTIVE

To examine the incidence of and risk factors for development of hyperlipidaemia in patients undergoing radical nephrectomy (RN) or partial nephrectomy (PN) for renal cortical neoplasms, as hyperlipidaemia is a major source of morbidity in chronic kidney disease (CKD).

PATIENTS AND METHODS

We conducted a two-centre retrospective analysis of 905 patients (mean age 57.5 years, mean follow-up 78 months), who underwent RN (n = 610) or PN (n = 295) between July 1987 and June 2007. Demographics, preoperative and postoperative hyperlipidaemia were recorded. De novo hyperlipidaemia was defined as that ocurring ≥6 months after surgery in cases where laboratory values met National Cholesterol Education Program Adult Treatment Panel III definitions. The Kaplan-Meier method was used to assess freedom from de novo hyperlipidaemia. Multivariable analysis was conducted to determine the risk factors for de novo hyperlipidaemia.

RESULTS

There were no significant differences with respect to demographics, preoperative glomerular filtration rate (GFR) <60 mL/min/1.73 m(2) (P = 0.123) and hyperlipidaemia (P = 0.144). Tumour size (cm) was significantly larger in the RN group vs the PN group (7.0 vs 3.7; P < 0.001). Significantly greater postoperative GFR <60 mL/min/1.73 m(2) was noted in the RN group (45.7 vs 18%, P < 0.001). Significantly, more de novo hyperlipidaemia developed in the RN group than in the PN group (23 vs 6.4%; P < 0.001). The mean time to development of hyperlipidaemia was longer for PN than for RN (54 vs 44 months; P = 0.03). Five-year freedom from de novo hyperlipidaemia probability was 76% for RN vs 96% for PN (P < 0.001). Multivariable analysis showed that RN (odds ratio [OR] 2.93; P = 0.0107), preoperative GFR <60 mL/min/1.73 m(2) (OR 1.98; P = 0.037) and postoperative GFR <60 mL/min/1.73 m(2) (OR 7.89; P < 0.001) were factors associated with hyperlipidaemia development.

CONCLUSION

Patients who underwent RN had a significantly higher incidence of and shorter time to development of de novo hyperlipidaemia. RN and pre- and postoperative eGFR <60 mL/min/1.73 m(2) were associated with development of hyperlipidaemia. Further follow-up and prospective investigation are necessary to confirm these findings.

Pilot investigation of variants in DNA repair pathways and association with response to platinum-based chemotherapy in bladder cancer

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Background: Germline single-nucleotide variations (SNVs) in DNA repair genes may have a role in response to platinum-based chemotherapy in bladder cancer (BC). As a pilot project we created a discovery cohort using an extreme phenotype model of BC response to neoadjuvant chemotherapy; we identified candidate SNVs in DNA repair genes via whole exome sequencing, and sought to replicate these findings in a validation cohort. Methods: We sequenced exomes of a discovery cohort with ≥ cT2 BC and neoadjuvant chemotherapy [6 complete responders (CR, pT0N0 and 1 year disease free interval) vs. 9 non-responders]. We identified SNVs within 377 DNA repair pathway genes. We filtered for SNVs with high impact effects, and moderate impact missense variants. The discovery phase resulted in 16 candidate SNVs which we genotyped (matrix-assisted laser desorption/ionization-time of flight) within a validation cohort of 303 BC patients treated with platinum-based neoadjuvant or first-line chemotherapy. Primary outcome was pathologic (neoadjuvant) or radiographic (first-line) CR, with secondary outcome CR+partial response (PR; RECIST criteria or pathologic downstaging). We used additive genetic model and logistic regression to analyze association between individual SNVs and both CR and CR+PR. Multivariate models included MSK risk score for CR or chemotherapy (cis- vs carboplatin) for CR+PR. Results: We included 303 patients (186 neoadjuvant, 117 first-line; 272 cisplatin, 31 carboplatin), median age 64, including 67 (22%) CR and 153 (50%) CR+PR. Genotyping was adequate for analysis in 14 of 16 SNVs—none were associated with CR. SNVs associated with CR+PR were rs2072454 (EGFR, p=0.031 unadjusted, p=0.035 adjusted for chemotherapy) and rs1805321 (PMS2, p=0.014 unadjusted, p=0.019 adjusted for chemotherapy). Findings were not significant after adjusting for multiple comparisons. Conclusions: Using an extreme phenotype model we identified SNVs in genes of the DNA repair pathway that may have an association with platinum-based chemotherapy response in BC. A larger validation study is required to increase power and reduce the impact of multiple testing prior to confirming significance.

Determinants of renal functional decline after open partial nephrectomy: a comparison of warm, cold, and non-ischemic modalities

INTRODUCTION

Renal functional decline after partial nephrectomy (PN) may be related to a variety of nonmodifiable and modifiable factors, including ischemia time (IT) and modality. We sought to determine the impact of these factors on renal functional degeneration after PN.

MATERIALS AND METHODS

Multicenter retrospective analysis (n = 347) was performed, identifying patients who underwent open PN using warm, cold, and non-ischemic techniques. Primary outcome was development of de novo chronic kidney disease (CKD), (estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2), at 1 year follow up. Univariate and multivariable analysis (MVA) were performed examining factors associated with ischemia technique and the development of de novo CKD.

RESULTS

Median follow up 34.7 months. Two hundred and forty-one patients underwent warm ischemic, 31 cold ischemic, and 75 clampless PN. Patient characteristics were similar between groups. Clampless group had lower mean RENAL scores (6.4) than cold (7.9, p = 0.005) and warm (7, p = 0.037) ischemia groups. Cold ischemia cohort had longer median IT than the warm cohort (50min versus 25 min, p = 0.001). There were no significant differences in proportion of patients developing de novo CKD (warm 14.9%, cold 15%, clampless 8.7%, p = 0.422). MVA demonstrated that neither ischemic modality nor IT ≥ 30 minutes was associated with development of de novo CKD, while RENAL scores of increasing complexity (RENAL score 7-9 OR 4.32, p = 0.003; RENAL score ≥ 10 OR 15.42, p < 0.001) were independently associated with de novo CKD.

CONCLUSIONS

Increasing tumor complexity, as indicated by the RENAL score, was an overriding determinant of post PN renal functional outcome. Prospective investigation is requisite to elucidate risk and protective factors for renal functional degeneration after PN.

Differentiation of clear from non-clear cell renal cell carcinoma using CT washout formula

INTRODUCTION

To further elucidate potential patterns of contrast enhancement for renal neoplasm subtypes, we investigated utility of contrast washout formula to differentiate renal tumor histology after multiphase computerized tomography (CT).

MATERIALS AND METHODS

Single center retrospective cohort study of 163 patients with multiphase CT for renal masses obtained October 2007 to July 2012. Pathology confirmed clear cell (CC-RCC; n = 92), papillary (Pa-RCC; n = 43), chromophobe (Ch-RCC; n = 6), oncocytoma (OC; n = 11), or angiomyolipoma (AML; n = 11) histology. Two radiologists in consensus and blinded to histology recorded tumor size, morphology, and attenuation measurements in Hounsfield Units (HU). Data were analyzed between subgroups based on histology. Enhancement washout of the tumor was calculated by the formula (Mass nephrographic HU-Mass delayed HU)/(Mass nephrographic HU-Mass non-contrast HU) and used to calculate sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV).

RESULTS

Tumor size was largest among CC-RCC (p < 0.001). Homogeneous composition was more common among Pa-RCC and Ch-RCC (p < 0.001). Median washout for Ch-RCC (0.27) was significantly different from that of OC (0.54, p = 0.05). Overall 25 (15.3%) of tumors had washout < 0. Tumors with washout value < 0 were Pa-RCC 24/43 (56%), and Ch-RCC 1/6 (14%). Washout value < 0 had a specificity of 99.2% for Pa-RCC and 100% for non-CC-RCC. Washout value ≥ 0 had a sensitivity and NPV of 100% for CC-RCC, OC, and AML. Washout value ≥ 0 had a specificity of 35.2% and a PPV of 66.7% for CC-RCC.

CONCLUSIONS

Enhancement washout value < 0 is highly specific for Pa-RCC and non-CC-RCC. Washout value ≥ 0 is highly sensitive for CC-RCC, OC, and AML while there was a significant difference in median washout between OC and Ch-RCC. Further prospective investigation is requisite to confirm these findings.

Comparison of transrectal and transvaginal hybrid natural orifice transluminal endoscopic surgery partial nephrectomy in the porcine model

OBJECTIVE

To compare the feasibility of porcine transrectal (TR) and transvaginal (TV) hybrid natural orifice transluminal endoscopic surgery (NOTES) partial nephrectomy (PN), as NOTES nephrectomy has recently been performed in the porcine model.

MATERIALS AND METHODS

A total of 10 female pigs (weight 45 kg) underwent TR (n = 5) or TV (n = 5) NOTES PN. The pneumoperitoneum was created by a periumbilical 12-mm trocar, through which a laparoscope was advanced for intra-abdominal visualization. For TV-NOTES PN, a gastroscope was used to obtain TV peritoneal access. For TR-NOTES PN, a horizontal incision was made 2 cm above the dentate line, and a submucosal tunnel was created in the posterior rectal wall. The gastroscope was advanced through the submucosal tunnel and retroperitoneum to the kidney, and a peritoneal window was created. For both TR- and TV-NOTES PN, the gastroscope was exchanged for the SPIDER Surgical System. Flexible dissecting instruments and hook cautery introduced through the SPIDER Surgical System were used to mobilize the kidney. A harmonic scalpel introduced periumbilically was used to excise a portion of the lower pole. LAPRA-TY-secured sutured renorrhaphy was performed, followed by TR or TV specimen extraction.

RESULTS

TR- and TV-NOTES PN was successfully performed in all 10 pigs. A comparison of TR- and TV-NOTES PN revealed no significant differences in the mean access time (29.2 vs 29.6 minutes, P = .944), operative time (196.0 vs 183.0 minutes, P = .631), and estimated blood loss (59.0 vs 54.0 mL, P = .861). Necropsy did not demonstrate abdominal injuries.

CONCLUSION

We have demonstrated proof-of-principle for TR and TV-NOTES PN in swine, with comparable perioperative parameters. Preclinical survival studies are requisite to assess the potential of TR-NOTES as an alternative to TV-NOTES.

The burden of urinary incontinence and urinary bother among elderly prostate cancer survivors

BACKGROUND

Data describing urinary health in elderly, community-dwelling prostate cancer (PCa) survivors are limited.

OBJECTIVE

To elucidate the prevalence of lower urinary tract symptoms, urinary bother, and incontinence in elderly PCa survivors compared with peers without PCa.

DESIGN, SETTING, AND PARTICIPANTS

A cross-sectional analysis of 5990 participants in the Osteoporotic Fractures in Men Research Group, a cohort study of community-dwelling men ≥ 65 yr.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We characterized urinary health using self-reported urinary incontinence and the American Urological Association Symptom Index (AUA-SI). We compared urinary health measures according to type of PCa treatment in men with PCa and men without PCa using multivariate log-binomial regression to generate prevalence ratios (PRs).

RESULTS AND LIMITATIONS

At baseline, 706 men (12%) reported a history of PCa, with a mean time since diagnosis of 6.3 yr. Of these men, 426 (60%) reported urinary incontinence. In adjusted analyses, observation (PR: 2.11; 95% confidence interval [CI], 1.22-3.65; p=0.007), surgery (PR: 4.41; 95% CI, 3.79-5.13; p<0.0001), radiation therapy (PR: 1.49; 95% CI, 1.06-2.08; p=0.02), and androgen-deprivation therapy (ADT) (PR: 2.02; 95% CI, 1.31-3.13; p=0.002) were each associated with daily incontinence. Daily incontinence risk increased with time since diagnosis independently of age. Observation (PR: 1.33; 95% CI, 1.00-1.78; p=0.05), surgery (PR: 1.25; 95% CI, 1.10-1.42; p=0.0008), and ADT (PR: 1.50; 95% CI, 1.26-1.79; p<0.0001) were associated with increased AUA-SI bother scores. Cancer stage and use of adjuvant or salvage therapies were not available for analysis.

CONCLUSIONS

Compared with their peers without PCa, elderly PCa survivors had a two-fold to five-fold greater prevalence of urinary incontinence, which rose with increasing survivorship duration. Observation, surgery, and ADT were each associated with increased urinary bother. These data suggest a substantially greater burden of urinary health problems among elderly PCa survivors than previously recognized.

Does timing of cytoreductive nephrectomy impact patient survival with metastatic renal cell carcinoma in the tyrosine kinase inhibitor era? A multi-institutional study

OBJECTIVE

To compare outcomes of metastatic renal cell carcinoma (mRCC) patients who underwent primary cytoreductive nephrectomy (CRN), followed by adjuvant sunitinib therapy, vs those who underwent primary sunitinib therapy before planned CRN.

METHODS

This was a multi-institutional retrospective analysis of 35 mRCC patients from June 2005 to August 2009 (median follow-up, 28.5 months): 17 underwent primary CRN, followed by adjuvant sunitinib (group 1); 18 underwent primary sunitinib therapy, followed by planned CRN (group 2). Response to therapy was determined using Response Evaluation Criteria in Solid Tumors. Group 2 patients who had partial response (PR)/stable disease (SD) proceeded to CRN (group 2 +CRN). Group 2 patients who progressed were treated with salvage systemic therapy (group 2 no-CRN). Primary and secondary outcomes were disease-specific survival (DSS) and overall survival (OS).

RESULTS

Patient demographic and tumor characteristics were similar. The groups had similar rates of DSS and OS on univariate analysis (P = .318 and P = .181). In group 2, 11 (61%) had PR/DS; 7 (39%) progressed. Mean times to disease-specific death in group 1, group 2 (+CRN), and group 2 (no-CRN) were 29.2, 4.6, and 28.7 months, respectively (P = .025). Kaplan-Meier analysis of DSS and OS demonstrated significant improvement in group 2 (+CRN) vs group 1 vs group 2 (no-CRN; P <.001), which remained significant on multivariate regression.

CONCLUSION

Nonresponders to primary sunitinib therapy had a poor prognosis. Offering CRN, if safely feasible, combined with sunitinib, was associated with improved disease-specific outcome in mRCC. Responders to primary sunitinib who underwent CRN had better DSS and OS than patients who underwent primary CRN, followed by sunitinib. Further investigation is required to assess the role, timing, and sequencing of targeted therapy and CRN in treatment of mRCC.

Comparison of laparoendoscopic single-site and multiport laparoscopic radical and partial nephrectomy: a prospective, nonrandomized study

OBJECTIVE

To prospectively compare outcomes of laparoendoscopic single-site and multiport laparoscopic radical nephrectomy and partial nephrectomy, focusing on postoperative pain and analgesic requirement.

METHODS

Nonrandomized, prospective comparison of laparoendoscopic single-site and multiport laparoscopic radical nephrectomy and partial nephrectomy. Thirty-four patients underwent laparoendoscopic single-site (17 radical nephrectomy/17 partial nephrectomy); 42 underwent multiport laparoscopy (28 radical nephrectomy/14 partial nephrectomy) from February 2009 to February 2010. Laparoendoscopic single-site transperitoneal access was obtained by periumbilical incision through which all trocars were inserted. Laparoendoscopic radical nephrectomy/partial nephrectomy recapitulated steps of multiport laparoscopic radical nephrectomy/partial nephrectomy. Demographics/tumor characteristics, outcomes, and complications were analyzed.

RESULTS

Forty-two of 42 multiport laparoscopic and 32/34 laparoendoscopic single-site cases were successfully performed. Mean follow-up was 16.2 months. For laparoendoscopic single-site and multiport laparoscopy groups mean operating room time (min) was 159.3 vs 158.9 (P = .952); mean estimated blood loss (mL) was 175.7 vs 156.1 (P = .553); percent transfused was 2.9% vs 0% (P = .925). No significant differences in complications were noted (P = .745). Significant decrease in analgesic use (6 morphine equivalents vs 11.6, P < .001) and discharge pain score (1.7 vs 2.7, P < .01) were noted in laparoendoscopic single-site vs multiport laparoscopic radical nephrectomy. For laparoendoscopic single-site partial nephrectomy and multiport laparoscopic partial nephrectomy, no significant differences were noted for tumor diameter (1.8 vs 2.0 cm, P = .57), RENAL score (0.962), ischemia time (28.6 vs 27.5 minutes, P = .70), and preoperative (P = .78)/postoperative creatinine (P = .32). For laparoendoscopic single-site radical nephrectomy and multiport laparoscopic radical nephrectomy, no significant differences were noted for mean tumor diameter (5.6 vs 5.3 cm, P = .63), RENAL score (P = .815), and mean operative time (142.3 vs 155.4 minutes P = .13).

CONCLUSION

In this well-matched, prospective comparison, laparoendoscopic single-site is comparable with multiport laparoscopic surgery in terms of perioperative parameters and may confer benefit with respect to analgesic requirement. Randomized evaluation and longer-term follow-up are necessary.

Does radical nephrectomy increase the risk of erectile dysfunction compared with partial nephrectomy? A cohort analysis

Study Type - Therapy (prospective cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Erectile dysfunction (ED) is a form of endothelial dysfunction that is prevalent in patients with chronic kidney disease (CKD). We hypothesized that partial nephrectomy (PN) would limit development of ED compared with radical nephrectomy (RN), primarily due to renal function preservation, and found that patients undergoing RN had significantly higher de novo ED compared with a contemporary, well-matched cohort undergoing PN; in addition to RN, hypertension, CKD and diabetes mellitus were associated with developing ED. To our knowledge, this is the first study demonstrating an increased risk of ED after RN compared with PN.

OBJECTIVES

•  To evaluate prevalence and risk factors for development of erectile dysfunction (ED) in patients who underwent radical nephrectomy (RN) and partial nephrectomy (PN). •  ED is a form of endothelial dysfunction that is prevalent in patients with chronic kidney disease (CKD). PN confers superior renal functional preservation compared with RN; however, the impact on ED is unclear.

METHODS

•  This was a retrospective study of 432 patients (264 RN/168 PN, mean age 58 years, mean follow-up 5.8 years) who underwent surgery for renal tumours between January 1998 and December 2007. •  The primary outcome was rate of de novo ED postoperatively. Secondary outcomes included development of CKD (estimated GFR < 60 mL/min/1.73 m(2) ) and response to phosphodiesterase-5 inhibitors. •  Multivariate analysis was performed to determine risk factors for de novo ED postoperatively.

RESULTS

•  RN and PN groups had similar demographics and comorbidities. •  Tumour size (cm) was larger for RN (RN 7.0 vs PN 3.7, P < 0.001) and more preoperative ED existed in PN vs RN (P= 0.042). No differences were observed for preoperative CKD, hyperlipidaemia and diabetes mellitus. •  Postoperatively, higher rates of de novo ED (29.5% vs 9.5%, P < 0.001) and CKD (33.0% vs 9.8%, P < 0.001) developed in RN vs PN cohorts, respectively. •  Of men with ED, 63% responded to phosphodiesterase inhibitors, without significant difference between the two groups (P= 0.896). •  Multivariate analysis demonstrated de novo ED to be associated with RN (odds ratio [OR] 3.56, P < 0.001), hypertension (OR 2.32, P= 0.014), preoperative (OR 8.77, P < 0.001) and postoperative (OR 2.64, P= 0.001) CKD, and postoperative diabetes mellitus (OR 2.93, P < 0.001).

CONCLUSIONS

•  Patients undergoing RN had significantly higher de novo ED compared with a contemporary, well-matched cohort undergoing PN. In addition to RN, hypertension, CKD and diabetes mellitus were associated with developing ED. •  Further investigation on effects of surgically induced nephron loss on ED is requisite.

Comparison of rates and risk factors for development of anaemia and erythropoiesis-stimulating agent utilization after radical or partial nephrectomy

OBJECTIVE

To examine the incidence of and risk factors for the development of anaemia and erythropoiesis-stimulation agent (ESA) treatment in patients undergoing radical nephrectomy (RN) and partial nephrectomy (PN) because anaemia is a significant cause of morbidity in chronic kidney disease.

PATIENTS AND METHODS

The study comprised a retrospective review of 905 patients (610 RN/295 PN; mean age, 57.5 years; mean follow-up, 6.4 years) who underwent surgery for renal tumours at two institutions from July 1987 to June 2007. Demographics, disease characteristics and pre- and postoperative (i.e. renal function, metabolic parameters, anaemia and ESA treatment) were recorded. Data were analyzed within subgroups based on treatment (RN vs PN). Multivariate analysis was conducted to determine the risk factors for developing anaemia after surgery.

RESULTS

Tumour size (cm) was significantly larger for RN (RN 7.0 vs PN 3.7; P < 0.001). No significant differences were noted with respect to demographics and preoperative anaemia (RN 16.4% vs PN 18.6%; P = 0.454) and ESA-treatment (RN 0.7% vs PN 1.4%; P = 0.499). After surgery, significantly less de novo anaemia (PN 4.1% vs RN 17.5%; P < 0.001) and ESA utilization (PN 2.7% vs RN 13.4%; P < 0.001) occurred in the PN cohort. Multivariate analysis showed that age ≥60 years (odds ratio, OR, 1.62; P = 0.008), African American ethnicity (OR, 2.30; P < 0.001), smoking (OR, 1.60; P = 0.013), glomerular filtration rate (GFR) <60 mL/min/1.73 m(2) (OR, 4.09; P < 0.001), ≥1+ proteinuria (OR, 2.19; P < 0.03), metabolic acidosis (OR, 4.08; P = 0.007) and RN (OR, 2.58; P < 0.001) were significantly associated with de novo anaemia.

CONCLUSIONS

Patients who underwent RN had a significantly higher prevalence of anaemia and ESA-treatment compared to a well-matched cohort that underwent PN. In addition to RN, age ≥60 years, African American ethnicity, history of smoking, GFR < 60 mL/min/1.73 m(2), proteinuria and metabolic acidosis were associated with developing anaemia.

Trends in adverse events of benign prostatic hyperplasia (BPH) in the USA, 1998 to 2008

OBJECTIVE

To determine if the adverse events (AEs) of benign prostatic hyperplasia (BPH) have declined in tandem with increased use of oral therapy.

MATERIALS AND METHODS

We used the Nationwide Inpatient Sample, a 20% sample of USA community hospitals, weighted to estimate national numbers to characterize the prevalence of AEs of BPH from 1998 to 2008. We calculated the age-adjusted prevalence of BPH and associated conditions and analyzed prevalence trends with regression modelling.

RESULTS

Of 134 million estimated eligible discharges during the study period, 7,464,730 (5.6%) had either a primary or secondary diagnosis of BPH. The age-adjusted prevalence of BPH among all hospitalizations, irrespective of primary diagnosis, increased from 4.3% to 8% (P < 0.001) during the study period. The age-adjusted prevalence of BPH as a primary diagnosis decreased from 0.88% to 0.48% (P < 0.001). Discharges for BPH surgery decreased 51% (odds ratio [OR] 0.49, 95% confidence interval [CI] 0.45-0.54, P-trend <0.001) over time. Discharges for primary BPH with acute renal failure increased >400% (OR 4.28, 95% CI 3.22-5.71, P-trend <0.001). There were no significant changes in discharges for primary BPH with urinary retention (P-trend = 0.636), bladder stones (P-trend = 0.117), or urinary infection (P-trend = 0.101) over time.

CONCLUSIONS

Increased hospitalizations for BPH with acute renal failure and stable hospitalizations for other AEs of BPH indicate that severe AEs of BPH persist despite widespread use of oral therapies in the USA. Further studies are needed to explain these trends.

Laparoscopic and percutaneous cryotherapy for renal neoplasms

Incidence of renal cell carcinoma is increasing. There has been a shift towards utilization of nephron sparing surgery when feasible. Minimally invasive ablative treatments such as laparoscopic and percutaneous renal cryoablation aim to treat renal tumors with the two goals of cancer eradication and reduced morbidity compared to excisional surgical approaches. In this article, we review the basis of cryobiology and examine the current role of renal cryoablation and analyze the current literature focusing on laparoscopic and percutaneous approaches and discuss future directions and refinements in cryosurgical technology. While renal cryoablation is associated with higher local retreatment rates compared to radical or partial nephrectomy, emerging reports of intermediate-term oncological outcomes suggest disease-specific survival approaching that of extirpative surgery. Further follow up is needed to elucidate the long-term oncologic outcomes of and effects on renal function by renal cryoablation.

Bladder perforation associated with hot tub

INTRODUCTION

Bladder perforation is a rare and life-threatening event. Timely diagnosis may prevent further injury-related morbidity and mortality. Aim.  To present a case of bladder injury associated with masturbation in a hot tub.

METHODS

This report describes a case of bladder perforation in a 54-year-old female who presented to the emergency department 2 days after masturbation with a water jet.

RESULTS

Following percutaneous drainage and intraoperative closure of the bladder, the patient was discharged on postoperative day four and has had no sequelae.

CONCLUSION

Cross-sectional imaging and cystography can facilitate immediate diagnosis and expeditious treatment of bladder injury associated with masturbation in a hot tub.

Laparo-endoscopic single-site (LESS) radical nephrectomy with renal vein thrombectomy: initial report

BACKGROUND

By combining trocar sites and extraction incision, Laparo-endoscopic Single-site Surgery (LESS) may provide less morbidity than traditional laparoscopy. Concerns continue about LESS for locally advanced tumors. We present our experience with LESS-radical nephrectomy with renal vein thrombectomy (LESS-RN-RVT) CASE PRESENTATION: Between 5-6/2009, 2 patients underwent LESS-RN-RVT (1 right-/1 left-side). Standard steps of multi-site laparoscopic radical nephrectomy were performed, including stapled renal vein thrombectomy and intact specimen extraction. Both cases were successfully completed by LESS without complications. Mean tumor size was 7.8 cm, incision size 4.5 cm, operative time 152 min, EBL 100 ml, and hospital stay 2.5 days. Both patients had negative margins, and are alive at time of last follow-up. One did not require postoperative opiates.

CONCLUSIONS

LESS-RN-RVT is safe and feasible in selected patients with renal vein thrombi. Further accumulation of data and comparison to multiport laparoscopic technique are requisite.

Recurrent nephrogenic adenoma in a 10-year-old boy with prune belly syndrome : a case presentation

Nephrogenic adenoma is a rare benign lesion of the urinary tract that is associated with a history of irritation or injury of the urothelium. Predisposing factors include infection, calculi, surgery, trauma, and renal transplantation. Nephrogenic adenoma commonly presents with lower urinary tract symptoms or hematuria. We present the case of recurrent nephrogenic adenoma in a 10-year-old boy with a history of prune belly syndrome and discuss management of this disease in the pediatric population. To our knowledge this represents the first reported case of recurrent nephrogenic adenoma associated with prune belly syndrome.

HMGB1 expression and release by bone cells

Immune and bone cells are functionally coupled by pro-inflammatory cytokine intercellular signaling networks common to both tissues and their crosstalk may contribute to the etiologies of some immune-associated bone pathologies. For example, the receptor activator of NF-kappaB ligand (RANKL)/osteoprotegerin (OPG)/receptor activator of NF-kappaB (RANK) signaling axis plays a critical role in dendritic cell (DC) function as well as bone remodeling. The expression of RANKL by immune cells may contribute to bone loss in periodontitis, arthritis, and multiple myeloma. A recent discovery reveals that DCs release the chromatin protein high mobility group box 1 (HMGB1) as a potent immunomodulatory cytokine mediating the interaction between DCs and T-cells, via HMGB1 binding to the membrane receptor for advanced glycation end products (RAGE). To determine whether osteoblasts or osteoclasts express and/or release HMGB1 into the bone microenvironment, we analyzed tissue, cells, and culture media for the presence of this molecule. Our immunohistochemical and immunocytochemical analyses demonstrate HMGB1 expression in primary osteoblasts and osteoclasts and that both cells express RAGE. HMGB1 is recoverable in the media of primary osteoblast cultures and cultures of isolated osteoclast precursors and osteoclasts. Parathyroid hormone (PTH), a regulator of bone remodeling, attenuates HMGB1 release in cultures of primary osteoblasts and MC3T3-E1 osteoblast-like cells but augments this release in the rat osteosarcoma cell line UMR 106-01, both responses primarily via activation of adenylyl cyclase. PTH-induced HMGB1 discharge by UMR cells exhibits similar release kinetics as reported for activated macrophages. These data confirm the presence of the HMGB1/RAGE signaling axis in bone.

Peroxisome proliferator-activated receptor coactivator-1alpha (PGC-1alpha) coactivates the cardiac-enriched nuclear receptors estrogen-related receptor-alpha and -gamma. Identification of novel leucine-rich interaction motif within PGC-1alpha

The transcriptional coactivator PPARgamma coactivator-1alpha (PGC-1alpha) has been characterized as a broad regulator of cellular energy metabolism. Although PGC-1alpha functions through many transcription factors, the PGC-1alpha partners identified to date are unlikely to account for all of its biologic actions. The orphan nuclear receptor estrogen-related receptor alpha (ERRalpha) was identified in a yeast two-hybrid screen of a cardiac cDNA library as a novel PGC-1alpha-binding protein. ERRalpha was implicated previously in regulating the gene encoding medium-chain acyl-CoA dehydrogenase (MCAD), which catalyzes the initial step in mitochondrial fatty acid oxidation. The cardiac perinatal expression pattern of ERRalpha paralleled that of PGC-1alpha and MCAD. Adenoviral-mediated ERRalpha overexpression in primary neonatal cardiac mycoytes induced endogenous MCAD expression. Furthermore, PGC-1alpha enhanced the transactivation of reporter plasmids containing an estrogen response element or the MCAD gene promoter by ERRalpha and the related isoform ERRgamma. In vitro binding experiments demonstrated that ERRalpha interacts with PGC-1alpha via its activation function-2 homology region. Mutagenesis studies revealed that the LXXLL motif at amino acid position 142-146 of PGC-1alpha (L2), necessary for PGC-1alpha interactions with other nuclear receptors, is not required for the PGC-1alpha.ERRalpha interaction. Rather, ERRalpha binds PGC-1alpha primarily through a Leu-rich motif at amino acids 209-213 (Leu-3) and utilizes additional LXXLL-containing domains as accessory binding sites. Thus, the PGC-1alpha.ERRalpha interaction is distinct from that of other nuclear receptor PGC-1alpha partners, including PPARalpha, hepatocyte nuclear factor-4alpha, and estrogen receptor alpha. These results identify ERRalpha and ERRgamma as novel PGC-1alpha interacting proteins, implicate ERR isoforms in the regulation of mitochondrial energy metabolism, and suggest a potential mechanism whereby PGC-1alpha selectively binds transcription factor partners.