Paul H. Chung

Magnetic Resonance Imaging/Ultrasound Fusion Guided Prostate Biopsy Improves Cancer Detection Following Transrectal Ultrasound Biopsy and Correlates With Multiparametric Magnetic Resonance Imaging

PURPOSE A novel platform was developed that fuses pre-biopsy magnetic resonance imaging with real-time transrectal ultrasound imaging to identify and biopsy lesions suspicious for prostate cancer. The cancer detection rates for the first 101 patients are reported. MATERIALS AND METHODS This prospective, single institution study was approved by the institutional review board. Patients underwent 3.0 T multiparametric magnetic resonance imaging with endorectal coil, which included T2-weighted, spectroscopic, dynamic contrast enhanced and diffusion weighted magnetic resonance imaging sequences. Lesions suspicious for cancer were graded according to the number of sequences suspicious for cancer as low (2 or less), moderate (3) and high (4) suspicion. Patients underwent standard 12-core transrectal ultrasound biopsy and magnetic resonance imaging/ultrasound fusion guided biopsy with electromagnetic tracking of magnetic resonance imaging lesions. Chi-square and within cluster resampling analyses were used to correlate suspicion on magnetic resonance imaging and the incidence of cancer detected on biopsy. RESULTS Mean patient age was 63 years old. Median prostate specific antigen at biopsy was 5.8 ng/ml and 90.1% of patients had a negative digital rectal examination. Of patients with low, moderate and high suspicion on magnetic resonance imaging 27.9%, 66.7% and 89.5% were diagnosed with cancer, respectively (p <0.0001). Magnetic resonance imaging/ultrasound fusion guided biopsy detected more cancer per core than standard 12-core transrectal ultrasound biopsy for all levels of suspicion on magnetic resonance imaging. CONCLUSIONS Prostate cancer localized on magnetic resonance imaging may be targeted using this novel magnetic resonance imaging/ultrasound fusion guided biopsy platform. Further research is needed to determine the role of this platform in cancer detection, active surveillance and focal therapy, and to determine which patients may benefit.

Robot-assisted laparoscopic partial nephrectomy for tumors greater than 4 cm and high nephrometry score: feasibility, renal functional, and oncological outcomes with minimum 1 year follow-up.

OBJECTIVES Minimally invasive robotic assistance is being increasingly utilized to treat larger complex renal masses. We report on the technical feasibility and renal functional and oncologic outcomes with minimum 1 year follow-up of robot-assisted laparoscopic partial nephrectomy (RALPN) for tumors greater than 4 cm. MATERIALS AND METHODS The urologic oncology database was queried to identify patients treated with RALPN for tumors greater than 4 cm and a minimum follow-up of 12 months. We identified 19 RALPN on 17 patients treated between June 2007 and July 2009. Two patients underwent staged bilateral RALPN. Demographic, operative, and pathologic data were collected. Renal function was assessed by serum creatinine levels, estimated glomerular filtration rate, and nuclear renal scans assessed at baseline, 3, and 12 months postoperatively. All tumors were assigned R.E.N.A.L. nephrometry scores (http://www.nephrometry.com). RESULTS The median nephrometry score for the largest tumor from each kidney was 9 (range 6-11) while the median size was 5 cm (range 4.1-15). Three of 19 cases (16%) required intraoperative conversion to open partial nephrectomy. No renal units were lost. There were no statistically significant differences between preoperative and postoperative creatinine and eGFR. A statistically significant decline of ipsilateral renal scan function (49% vs. 46.5%, P = 0.006) was observed at 3 months and at 12 mo postoperatively (49% vs. 45.5%, P = 0.014). None of the patients had evidence of recurrence or metastatic disease at a median follow-up of 22 months (range 12-36). CONCLUSIONS RALPN is feasible for renal tumors greater than 4 cm with moderate or high nephrometry scores. Although there was a modest decline in renal function of the operated unit, RALPN may afford the ability resect challenging tumors requiring complex renal reconstruction. The renal functional and oncologic outcomes are promising at a median follow-up of 22 months, but longer follow-up is required.

Renal Cell Carcinoma with Metastases to the Gallbladder: Four Cases from the National Cancer Institute (NCI) and Review of the Literature

OBJECTIVE We evaluate presentation and outcome of patients with metastatic RCC to the gallbladder from our institution and published literature. METHODS Patients with a history of gallbladder metastasis from RCC were selected from our institutions prospective database. A systematic PubMed search was performed to identify articles describing patients with metastatic RCC to the gallbladder. The final cohort included 33 patients: 4 from our institution and 29 from 28 previously published cases. Survival analysis was conducted using log-rank Kaplan-Meier analysis. RESULTS Median patient age was 63 years and the majority of patients were male. Most patients were asymptomatic and diagnosed with gallbladder metastasis on imaging performed for surveillance or staging. The median time to gallbladder metastasis following nephrectomy was 4 years. Metastasis to the gallbladder occurred both synchronously (33%) and metachronously (67%). Of the patients with available histology, all had clear cell RCC (n = 28). Of all patients, 13 (39%) had metastasis only to the gallbladder, while 20 (61%) had additional sites of metastasis. The most common sites of additional metastasis were contralateral kidney (30%), pancreas (21%), lung (18%), adrenal (18%), and lymph nodes (9%). All patients underwent cholecystectomy. At a median follow up time of 1.5 years after cholecystectomy, 54% of patients had no evidence of disease, 14% were alive with metastasis, 23% had died from metastatic RCC, and 9% died from causes unrelated to their cancer. CONCLUSION Gallbladder metastasis from RCC is a rare event that may occur synchronously or metachronously with most patients being asymptomatic. Clear cell carcinoma appears to be the primary pathology associated with gallbladder metastasis. High rates of bilateral RCC and pancreatic metastasis suggest novel associations in patients with RCC and gallbladder metastasis.

Degree of hydronephrosis predicts adverse pathological features and worse oncologic outcomes in patients with high-grade urothelial carcinoma of the upper urinary tract

OBJECTIVE To evaluate degree of hydronephrosis (HN) as a surrogate for adverse pathological features and oncologic outcomes in patients with high-grade (HG) and low-grade (LG) upper tract urothelial carcinomas (UTUCs). METHODS We retrospectively reviewed 141 patients with localized UTUCs that underwent extirpative surgery at a tertiary referral center. Preoperative imaging was used to evaluate presence and degree of ipsilateral HN. We evaluated degree of HN (none/mild vs. moderate/severe), pathological findings, and oncologic outcomes. RESULTS HG UTUC was present in 113 (80%) patients, muscle-invasive disease (≥pT2) in 49 (35%), and non-organ-confined disease (≥pT3) in 41 (29%). At a median follow-up of 34 months, 49 (35%) patients experienced intravesical recurrence, 28 (20%) developed local/systemic recurrence, and 24 (17%) died of UTUC. HN was graded as none/mild in 77 (55%) patients and moderate/severe in 64 (45%). In patients with HG UTUC, but not LG, degree of HN was associated with advanced pathological stage (P<0.001), positive lymph nodes (P = 0.01), local/systemic recurrence-free survival (hazard ratio [HR] = 5.5, P = 0.02), and cancer-specific survival (HR = 5.2, P = 0.02). On multivariable analysis of preoperative factors, degree of HN in patients with HG UTUC was associated with muscle invasion (HR = 9.3; 95% CI: 3.08-28.32; P<0.001), non-organ-confined disease (HR = 4.5; 95% CI: 1.66-12.06; P = 0.003), local/systemic recurrence-free survival (HR = 2.5; 95% CI: 1.07-5.64; P = 0.04), and cancer-specific survival (HR = 2.6; 95% CI: 1.05-6.22; P = 0.04). CONCLUSIONS Degree of HN can serve as a surrogate for advanced disease and predict worse oncologic outcomes in HG UTUC. Degree of HN was not predictive of intravesical or local/systemic recurrence in LG UTUC.

Emerging drugs for prostate cancer

Introduction: Androgen deprivation therapy is the mainstay treatment for patients with prostate cancer who are not candidates for definitive treatment, are diagnosed with advanced disease on initial presentation or progress after primary treatment. Patients who stop responding to androgen deprivation therapy develop castration resistant prostate cancer (CRPC). Emerging drugs undergoing clinical evaluation and drugs that have recently received FDA approval for the treatment of CRPC are reviewed. Areas covered: As the natural history and signaling pathways of prostate cancer are better understood, new treatments and targeted therapies will be developed. The FDA recently approved 5 medications that increase survival in patients with CRPC. Additional medications and drug classes are being explored that may eventually lead to new treatment options. Articles were identified using a PubMed database search. Expert opinion: Recent FDA medication approvals and the development of emerging treatments are promising for the future of patients with prostate cancer. The addition of new medications challenges physicians to identify the optimal sequence and/or combination in which newer and older medications should be administered. Physicians treating patients with prostate cancer have a growing responsibility to keep pace with these new medications so that they may counsel and treat patients appropriately.

Molecular sub-classification of renal epithelial tumors using meta-analysis of gene expression microarrays.

Purpose To evaluate the accuracy of the sub-classification of renal cortical neoplasms using molecular signatures. Experimental Design A search of publicly available databases was performed to identify microarray datasets with multiple histologic sub-types of renal cortical neoplasms. Meta-analytic techniques were utilized to identify differentially expressed genes for each histologic subtype. The lists of genes obtained from the meta-analysis were used to create predictive signatures through the use of a pair-based method. These signatures were organized into an algorithm to sub-classify renal neoplasms. The use of these signatures according to our algorithm was validated on several independent datasets. Results We identified three Gene Expression Omnibus datasets that fit our criteria to develop a training set. All of the datasets in our study utilized the Affymetrix platform. The final training dataset included 149 samples represented by the four most common histologic subtypes of renal cortical neoplasms: 69 clear cell, 41 papillary, 16 chromophobe, and 23 oncocytomas. When validation of our signatures was performed on external datasets, we were able to correctly classify 68 of the 72 samples (94%). The correct classification by subtype was 19/20 (95%) for clear cell, 14/14 (100%) for papillary, 17/19 (89%) for chromophobe, 18/19 (95%) for oncocytomas. Conclusions Through the use of meta-analytic techniques, we were able to create an algorithm that sub-classified renal neoplasms on a molecular level with 94% accuracy across multiple independent datasets. This algorithm may aid in selecting molecular therapies and may improve the accuracy of subtyping of renal cortical tumors.

Surgical and Functional Outcomes Following Buried Penis Repair With Limited Panniculectomy and Split-thickness Skin Graft

OBJECTIVE To report surgical and functional outcomes of buried penis surgery. METHODS Outcomes following buried penis surgery at the University of Washington were assessed from June 1, 2005 to June 1, 2016. Patient demographic and surgical data were abstracted from a retrospective chart review. All patients were attempted to be contacted by phone for long-term follow-up. Uni- and multivariate analysis was performed to evaluate for association with any complication. RESULTS A total of 42 men underwent buried penis repair surgery (mean short-term follow-up 8.1 months). There was an overall 33% 90-day complication rate (21 events). In univariate analysis, body mass index (BMI; P = .02) and no history of gastric bypass (P = .03) were significant predictors of any complication. In multivariate analysis, only BMI remained significant (odds ratio 1.1 for each increase in unit of BMI, 95% confidence interval 1.01-1.27). Twenty-seven patients were reached for long-term follow-up (mean 39 months). Patients reported improvements in every functional domain that was assessed. Of the patients, 85% reported they would undergo buried penis surgery again, 74% that surgery led to a positive change in their lives, and 85% that the surgery had remained a long-term success. CONCLUSION Surgical correction of buried penis with penile split-thickness skin graft and limited panniculectomy is well tolerated and results in functional, long-term improvements. BMI is associated with an increased likelihood of a complication following surgery.

Robotic Appendicovesicostomy Revision in Children: Description of Technique and Initial Results

PURPOSE To report our initial results of robotic appendicovesicostomy (APV) revision in children. PATIENTS AND METHODS Three patients (median age 6 years; range 6-13) underwent robot-assisted APV surgery for bladder dysfunction because of posterior urethral valves, myelomeningocele, and traumatic spinal cord transection. Leakage developed in each patient from the APV. After failing more conservative treatments, the patients subsequently underwent robot-assisted APV revision. RESULTS Robot-assisted APV revision was conducted at a median 14 months (range 6-34 mos) after initial surgery. Median operative time was 165 minutes (range 106-232 min), and blood loss was ≤5 mL for all patients. Intraoperative findings ranged from partial to complete separation of the APV from the bladder tunnel. APV leakage resolved for all patients at last follow-up (median 5 months; range 2-9 mos). CONCLUSION This initial series expands the scope of robotic surgical procedures in children. Robot-assisted APV revision was technically feasible and safe in this early experience.

Urethral Foreign Body: Removal of Degraded Magnetic Spheres Using Hartmann Ear Forceps

Lower urinary tract foreign bodies have been reported in both children and adults. It is helpful for urologists to review foreign body case reports to become familiar with alternative approaches for removal that may prove helpful during challenging cases. To our knowledge, we describe for the first time a degraded rare-earth magnet within the body and use of Hartmann ear forceps to remove a foreign body from the urethra under cystoscopic guidance through a limited urethrotomy.

Incidence of Stress Urinary Incontinence After Posterior Urethroplasty for Radiation-induced Urethral Strictures

OBJECTIVE To identify the frequency of de novo stress urinary incontinence (SUI) after posterior excision and primary anastomotic (EPA) urethroplasty in patients with radiation-induced urethral strictures (RIUS) and compare with patients with pelvic fracture urethral injuries (PFUIs). MATERIALS AND METHODS A retrospective review was conducted among patients who underwent successful posterior EPA urethroplasty between 2008 and 2016 for RIUS from prostate cancer or PFUI from blunt trauma. Only patients with an intact bladder neck on imaging were included. SUI was defined by patient-reported outcomes and daily pad use. RESULTS Inclusion criteria were met by 36 patients with RIUS and 33 patients with PFUI. Among the RIUS cohort, mean follow-up was 18 months, mean stricture length was 2.5 cm, and surgical dissection extended to the prostatic urethra in 67% (n = 24). The overall frequency of de novo SUI among patients with RIUS was 33% (n = 12), of which 75% (9 of 12) had prostatic urethral involvement. Two patients with RIUS (17%, n = 12) proceeded with artificial urinary sphincter (AUS) placement, whereas the remaining 10 patients required pads. SUI after urethroplasty in patients with PFUI was less common (12%, n = 4) and the prostatic urethra was involved in only 3% (n = 1) of all patients with PFUI. One patient with PFUI underwent AUS placement, whereas the remaining 3 patients did not require pads. CONCLUSION Among RIUS patients with an intact bladder neck, SUI impacts one-third of patients. Subsequent AUS placement is uncommon. Prostatic urethral involvement increases risk of SUI. SUI is less common among patients with PFUI, likely related to a more limited involvement of the proximal bulbomembranous urethra and lack of radiation.