Faculty Bibliography

PURPOSE/OBJECTIVE:Response rates to current second line intravesical therapies for recurrent nonmuscle invasive bladder cancer range between 10% and 30%. Nanoparticle albumin bound (nab-)paclitaxel has increased solubility and lower toxicity compared to other taxanes. Results of the phase I intravesical trial of this compound demonstrated minimal toxicity during dose escalation. We now report the results of a phase II trial to assess efficacy. MATERIALS AND METHODS/METHODS:This study was an investigator initiated, single center, single arm, phase II trial investigating the use of nab-paclitaxel in patients with recurrent Tis, T1 and Ta urothelial carcinoma in whom at least 1 prior regimen of intravesical bacillus Calmette-Guérin failed. Patients received 500 mg/100 ml nab-paclitaxel administered in 6 weekly intravesical instillations. Efficacy was evaluated with cystoscopy, biopsy, cytology and imaging. If complete response was achieved, patients were treated with full dose monthly maintenance treatments for 6 months. RESULTS:A total of 28 patients were enrolled in the study. Of these patients 10 (35.7%) exhibited a complete response after initial treatment. At 1 year all of these responses remained durable after maintenance therapy. At a mean followup of 21 months (range 5 to 47) 19 of 28 (67.8%) patients retained their bladders without progression or distant metastases. A single patient had progression to muscle invasive disease at radical cystectomy. Treatment related adverse events were noted in 9 of 28 (32.1%) patients and were limited to grade 1 or 2. CONCLUSIONS:Intravesical nab-paclitaxel has minimal toxicity and a 35.7% response rate in patients with nonmuscle invasive bladder cancer and previous bacillus Calmette-Guérin failure. Complete response remained durable at 1 year followup in this heavily pretreated patient population.

The intrinsic ability to exhibit self-organizing morphogenetic properties in ex vivo culture may represent a general property of tissue stem cells. Here we show that single luminal stem/progenitor cells can generate prostate organoids in a three-dimensional culture system in the absence of stroma. Organoids generated from CARNs (castration-resistant Nkx3.1-expressing cells) or normal prostate epithelia exhibit tissue architecture containing luminal and basal cells, undergo long-term expansion in culture and exhibit functional androgen receptor signalling. Lineage-tracing demonstrates that luminal cells are favoured for organoid formation and generate basal cells in culture. Furthermore, tumour organoids can initiate from CARNs after oncogenic transformation and from mouse models of prostate cancer, and can facilitate analyses of drug response. Finally, we provide evidence supporting the feasibility of organoid studies of human prostate tissue. Our studies underscore the progenitor properties of luminal cells, and identify in vitro approaches for studying prostate biology.

The definitive treatment for patients with high-risk non-muscle-invasive bladder cancer (NMIBC) who fail to respond to intravesical bacillus Calmette-Guérin (BCG) is cystectomy. However, many patients who experience recurrence after BCG are either poor operative candidates or refuse surgery due to the long-term impact on their quality of life. In the last decade, there has been an increased interest in alternative intravesical therapies, and several novel chemotherapeutics have emerged as promising agents for high-risk NMIBC patients unable or unwilling to undergo cystectomy. Additionally, extended treatment regimens with combined induction and maintenance therapy have been investigated, and may increase the durability of response to these new agents, as has been shown for conventional intravesical therapy.

PURPOSE/OBJECTIVE:Docetaxel is a safe agent for intravesical therapy. Adding monthly maintenance treatments can extend response durability. We report our cumulative experience with intravesical docetaxel in a larger cohort with extended followup. MATERIALS AND METHODS/METHODS:A total of 54 patients received salvage intravesical docetaxel for bacillus Calmette-Guérin refractory nonmuscle invasive bladder cancer between 2003 and 2012, including 18 treated during the original phase I trial. All patients received 6 weekly instillations of intravesical docetaxel. After the phase I trial, those with a complete response to induction treatment were offered single dose monthly maintenance treatments for a total of up to 12 months of docetaxel therapy. Recurrence was defined as positive biopsy or urine cytology. Recurrence-free, disease specific and overall survival was determined by Kaplan-Meier analysis. RESULTS:Median followup was 39.1 months. Of the 54 patients 32 (59%) had a complete initial response after induction therapy, including 18 who received additional monthly maintenance treatments. Median time to recurrence in initial responders treated with vs without docetaxel maintenance was 39.3 vs 19.0 months. One and 3-year recurrence-free survival rates for the entire cohort were 40% and 25%, respectively. Of the 54 patients 17 (24%) underwent radical cystectomy at a median of 24 months of followup. Five-year disease specific and overall survival rates were 85% and 71%, respectively. CONCLUSIONS:Intravesical docetaxel appears to be a promising agent with significant efficacy and durability for bacillus Calmette-Guérin refractory nonmuscle invasive bladder cancer. Adding maintenance treatments may increase the duration of recurrence-free survival.

OBJECTIVE:To examine the relationship between tumour diameter and estimated GFR (eGFR) in patients with renal cell carcinoma (RCC). PATIENTS AND METHODS/METHODS:In total, 1009 patients undergoing partial or radical nephrectomy for unilateral RCC were identified in the Columbia Urologic Database. eGFR was calculated using the modification of diet in renal disease equation using demographic data and preoperative serum creatinine values. Data on patient demographics, tumour characteristics, and comorbidities were analyzed using univariate and multivariate regression analysis. RESULTS:Mean (sd, range) tumour diameter was 5.29 (3.8, 0.3-29) cm. Mean (sd, range) eGFR was 75 (23.4, 3-173) mL/min per 1.73 m(2) . In multivariate regression analysis, tumour diameter independently predicted decreased preoperative eGFR (coefficient, -0.513; P= 0.008) when controlling for hypertension and race. Consistent with this, decreased preoperative eGFR independently predicted increased tumour diameter (coefficient, -0.013; P= 0.007) when controlling for race, histology and smoking status. CONCLUSION/CONCLUSIONS:Tumour diameter and decreased preoperative eGFR are independently correlated in patients with RCC.

BACKGROUND:Despite evidence supporting perioperative chemotherapy, few randomized studies compare neoadjuvant and adjuvant chemotherapy for bladder cancer. Consequently, the standard of care regarding the timing of chemotherapy for locally advanced bladder cancer remains controversial. We compared patient outcomes following neoadjuvant or adjuvant systemic chemotherapy for cT2-T4aN0-N2M0 bladder cancer. METHODS:In a retrospective review of a single institutional database from 1988 through 2009, we identified patients receiving neoadjuvant or adjuvant multiagent platinum-based systemic chemotherapy for locally advanced bladder cancer. Survival analysis was performed comparing disease-specific survival (DSS) and overall survival (OS). RESULTS:A total of 146 patients received systemic perioperative chemotherapy (73 neoadjuvant, 73 adjuvant). Of these, 84% (122/146) received cisplatin-based chemotherapy compared with carboplatin-based chemotherapy (24/146, 16.4%). Most patients receiving cisplatin-based chemotherapy were treated with methotrexate/vinblastine/adriamycin/cisplatin (79/122, 64.8%), whereas the remaining patients received gemcitabine/cisplatin (GC) (43/122, 35.2%). In multivariable analysis, there was no significant difference in DSS (P = .46) or OS (P = .76) between neoadjuvant or adjuvant chemotherapy groups. There was statistically significant improvement in DSS when patients received neoadjuvant GC rather than adjuvant GC (P = .049, hazard ratio, 10.6; 95% confidence interval, 1.01-112.2). CONCLUSION/CONCLUSIONS:In this study, there was no statistically significant difference in OS and DSS between patients receiving neoadjuvant versus adjuvant systemic platinum-based chemotherapy for locally advanced bladder cancer. In addition, there was no significant difference between neoadjuvant and adjuvant cisplatin- or carboplatin-based chemotherapy. Chemotherapy sequence relative to surgery appeared less important than whether or not a patient actually received perioperative chemotherapy.

PURPOSE/OBJECTIVE:Up to 50% of patients treated with intravesical agents for high grade nonmuscle invasive bladder cancer will have disease recurrence. Response rates to current second line intravesical therapies are low and for these high risk patients novel agents are necessary. Our previously completed phase I trial showed docetaxel was a safe agent for intravesical use. Nanoparticle albumin-bound paclitaxel (Abraxane®, ABI-007) has been shown to have increased solubility and lower toxicity compared to docetaxel in systemic therapy. Thus, we assessed the dose limiting toxicity and maximum deliverable dose of intravesical nanoparticle albumin-bound paclitaxel. MATERIALS AND METHODS/METHODS:Inclusion criteria for this institutional review board approved phase I trial were recurrent high grade Ta, T1 and Tis transitional cell carcinoma of the bladder for which at least 1 prior standard intravesical regimen failed. Six weekly instillations of nanoparticle albumin-bound paclitaxel were administered with a modified Fibonacci dose escalation model used until the maximum deliverable dose was achieved. The primary end point was dose limiting toxicity and the secondary end point was response rate. RESULTS:A total of 18 patients were enrolled in the study. One patient demonstrated measurable systemic absorption after 1 infusion. Grade 1 local toxicities were experienced by 10 (56%) patients with dysuria being the most common, and no grade 2, 3 or 4 drug related local toxicities were encountered. Of the 18 patients 5 (28%) had no evidence of disease at posttreatment evaluation. CONCLUSIONS:Intravesical nanoparticle albumin-bound paclitaxel exhibited minimal toxicity and systemic absorption in the first human intravesical phase I trial to our knowledge. A larger phase II study has begun to formally evaluate the activity of this regimen.

Serum tumor markers play a critical role in the diagnosis, staging, risk stratification, and surveillance of patients with testicular germ cell tumors (GCTs). Production of the oncofetal substances α fetoprotein and human chorionic gonadotropin can aid the diagnosis of testicular GCTs, and specific patterns of marker elevation can be used to determine the type of tumor, particularly as it pertains to nonseminoma. These markers, in addition to lactate dehydrogenase, have been incorporated in the standard TNM staging system for testicular tumors; the S stage category corresponds to serum elevation of these proteins. Furthermore, the degree of serum tumor marker elevation has been incorporated into standardized patient risk groupings, which are used to guide therapeutic management. The rate of tumor marker decay after radical orchiectomy is an important index to monitor, as a slow decline might be indicative of metastatic disease and should prompt a thorough systemic survey. The rate of tumor marker decline is already being utilized in the setting of metastatic GCTs to determine response to chemotherapy, and has been used in some scenarios to individualize the type of chemotherapy patients received. Compared to any other solid organ malignancy, the role of serum tumor markers in GCT is unprecedented; these markers are instrumental in the diagnosis and management of testicular GCT.

OBJECTIVE:To assess our institution's experience with the management of pathologic stage T3bNxM0 renal cell carcinoma with tumor thrombus confined to the renal vein treated with nephron-sparing surgery (NSS). METHODS:Of the 492 patients who have undergone NSS at Columbia University from 1998 to 2009, 8 patients were found to have stage T3bNxM0 renal cell carcinoma (RCC) on final pathology. Records were reviewed for indication for NSS, imaging studies, perioperative management, surgical details, pathology, and both functional and disease-specific outcomes. Postoperative renal function was estimated by most recent glomerular filtration rate using Modification of Diet in Renal Disease formula. Recurrence of RCC was monitored using serial axial imaging. RESULTS:The 8 patients were presumed to be clinical stage T1aN0M0 RCC before surgery; however, tumor thrombus was identified in the renal vein intraoperatively and on final pathology in 4, and 4 cases, respectively, corresponding to stage T3bNxM0 RCC by current American Joint Committee on Cancer-Tumor-Necrosis-Metastasis 2002 criteria. After a median follow-up of 19.8 months, the patients experienced a mean decrease in estimated glomerular filtration rate of 27.1%. One patient developed new-onset renal failure, defined as an estimated glomerular filtration rate below 30 mL/min/1.73 m(2). Clean surgical margins were obtained in 7 patients. Carcinoma was identified at the parenchymal margin in 1 patient. No patients have evidence of recurrence of RCC by serial axial imaging. CONCLUSIONS:NSS does not seem to have had a negative impact on a small series of patients with pathologic stage T3bNxM0 RCC limited to the renal vein and may be a feasible option when the clinical situation indicates a need for preservation of renal function.