LaMont Barlow

Single luminal epithelial progenitors can generate prostate organoids in culture

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.

Predicting renal functional outcomes after surgery for renal cortical tumours: a multifactorial analysis

Study Type – Therapy (case series)
Level of Evidence 4

Long-Term Survival Outcomes with Intravesical Docetaxel for Recurrent Nonmuscle Invasive Bladder Cancer After Previous Bacillus Calmette-Guérin Therapy

PURPOSE 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 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.

A Phase I Trial of Intravesical Nanoparticle Albumin-Bound Paclitaxel in the Treatment of Bacillus Calmette-Guérin Refractory Nonmuscle Invasive Bladder Cancer

PURPOSE 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 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.

Long-term clinical outcomes of a phase I trial of intravesical docetaxel in the management of non-muscle-invasive bladder cancer refractory to standard intravesical therapy.

OBJECTIVES To report the long-term clinical outcomes and durability of response after treatment with induction intravesical docetaxel. Most novel agents used to treat bacillus Calmette-Guerin refractory high-grade non-muscle-invasive (NMI) bladder cancer are evaluated only after short follow-up periods. Our previously published phase I trial demonstrated that docetaxel is a safe agent for intravesical therapy with minimal toxicity and no detectable systemic absorption. We sought to determine long-term clinical outcomes after treatment with intravesical docetaxel. METHODS Eighteen patients with recurrent Ta (n = 7), T1 (n = 5), and Tis (n = 6) transitional cell carcinoma who experienced treatment failure with at least 1 prior intravesical therapy completed the phase I trial. Docetaxel was administered as 6 weekly intravesical instillations using a dose-escalation model terminated at 0.75 mg/mL. Efficacy was evaluated by interval cystoscopy with biopsies when indicated, cytology, and computed tomography imaging. Follow-up consisted of quarterly cystoscopy, cytology, computed tomography, and biopsy when indicated. RESULTS With a median follow-up of 48.3 months, 4 patients (22%) have demonstrated a complete durable response and currently remain disease-free without further treatment. Three patients (17%) had a partial response, defined as a single NMI recurrence with no further therapy for bladder cancer. Eleven patients (61%) failed treatment, and required another intervention. One patient developed stage progression. No delayed toxicities were noted. The median disease-free survival time was 13.3 months. CONCLUSIONS After 4 years of follow-up without maintenance therapy, intravesical docetaxel has demonstrated the ability to prevent recurrence in a select number of patients with refractory NMI bladder cancer and warrants further investigation.

Serum tumor markers in the evaluation of male germ cell tumors

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.

A comparison of the outcomes of neoadjuvant and adjuvant chemotherapy for clinical T2-T4aN0-N2M0 bladder cancer.

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.

Single Institutional Experience with Nephron-sparing Surgery for Pathologic Stage T3bNxM0 Renal Cell Carcinoma Confined to the Renal Vein

OBJECTIVE To assess our institutions 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.

SnapShot: Prostate Cancer

ObservationMild symptomsCombine with other palliative measuresPre- or postdocetaxel treatmentPostdocetaxel (studies ongoing for predocetaxel use)Asymptomatic or minimally symptomaticPostdocetaxelBone metastases onlyTo symptomatic sites+/ -+/- /-+ /-+ /--/(+)+ ++++++Secondary hormone therapyDocetaxelAbiratironeEnzalutamideSipuleucel-TCabazitaxelRadium-223Palliative radiation therapy

Experience with Newer Intravesical Chemotherapy for High-Risk Non-Muscle-Invasive Bladder Cancer

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.