A. Trout

Phase II Study of Sunitinib in Patients With Metastatic Urothelial Cancer

PURPOSE No standard therapy exists for metastatic urothelial cancer (UC) that has progressed after initial chemotherapy. This trial was designed to assess the efficacy and tolerability of sunitinib in patients with advanced, previously treated UC. PATIENTS AND METHODS In this phase II trial, 77 patients received sunitinib between September 2006 and January 2009 on one of two schedules (50 mg per day for 4 weeks on and 2 weeks off [cohort A], 37.5 mg per day continuously [cohort B]), using a Simon 2 stage design in each cohort separately. RESULTS A partial response was seen in three of 45 patients (95% CI, 1% to 18%) in cohort A, and in one of 32 patients (95% CI, 0% to 16%) in cohort B. Clinical regression or stable disease was achieved in 33 of 77 patients (43%). Tumor regression lasted between 0.6 and 23.4 months with 29% of patients achieving response lasting longer than 3 months. The progression-free survival (2.4 v 2.3 months; P = .4) and overall survival (7.1 v 6.0 months; P = .4) were similar in both cohorts. There was one treatment-related death, and 47 patients (33 cohort A, 24 cohort B) experienced grade 3 or 4 toxicity. CONCLUSION Sunitinib did not achieve the predetermined threshold of >or= 20% activity defined by Response Evaluation Criteria in Solid Tumors. However, antitumor responses were observed, identifying the vascular endothelial growth factor axis as a viable pathway for UC treatment. The reported clinical benefit in previously treated patients warrants further investigation in a disease for which there is no US Food and Drug Administration-approved treatment.

Phase II study of everolimus in metastatic urothelial cancer

No recent advances have been made in the treatment of patients with advanced bladder cancer and, to date, targeted therapies have not resulted in an improvement in outcome. The mammalian target of rapamycin pathway has been shown to be up‐regulated in bladder cancer and represents a rational target for therapeutic intervention. In the present phase II study of everolimus, one near‐complete response, one partial response and several minor responses suggest that everolimus possesses biological activity in a subset of patients with bladder cancer. To maximize benefit from targeted agents such as everolimus, the preselection of patients based on molecular phenotype is required.

Clinical Value of Fluorine-18 2-Fluoro-2-Deoxy-D-Glucose Positron Emission Tomography/Computed Tomography in Bladder Cancer

PURPOSE Fluorine-18 2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) has been approved for imaging in many malignancies but not for bladder cancer. This study investigated the value of FDG-PET/CT imaging in the management of patients with advanced bladder cancer. PATIENTS AND METHODS Between May 2006 and February 2008, 57 patients with bladder cancer at our center underwent FDG-PET/CT after CT (n = 52) or magnetic resonance imaging (MRI; n = 5). The accuracy of FDG-PET/CT was assessed using both organ-based and patient-based analyses. FDG-PET/CT findings were validated by either biopsy or serial CT/MRI. Clinician questionnaires performed before and after FDG-PET/CT assessed whether those scan results affected management. RESULTS One hundred thirty-five individual lesions were evaluable in 47 patients for the organ-based analysis. Overall sensitivity and specificity were 87% (95% CI, 76% to 94%) and 88% (95% CI, 78% to 95%), respectively. In the patient-based analysis, malignant disease was correctly diagnosed in 25 of 31 patients, resulting in a sensitivity of 81% (95% CI, 63% to 93%). FDG-PET/CT was negative in 15 of 16 patients without malignant lesions for a specificity of 94% (95% CI, 71% to 100%). Pre- and post-PET surveys revealed that FDG-PET/CT detected more malignant disease than conventional CT/MRI in 40% of patients. Post-PET surveys showed that clinicians changed their planned management in 68% of patients based on the FDG-PET/CT results. CONCLUSION FDG-PET/CT has excellent sensitivity and specificity in the detection of metastatic bladder cancer and provides additional diagnostic information that enhances clinical management more than CT/MRI alone. FDG-PET/CT scans may provide better accuracy in clinical information for directing therapy.

Detection of circulating tumor cells in patients with urothelial cancer

BACKGROUND Approximately 50% of patients with metastatic urothelial cancer (UC) respond to chemotherapy and several months of therapy is required to assess for radiographic response. Blood-based biomarkers may identify patients in whom a specific therapy provides clinical benefit, and this study sought to characterize circulating tumor cells (CTCs) in patients with metastatic UC. PATIENTS AND METHODS Peripheral blood from patients with metastatic UC was evaluated for CTCs using the CellSearch system. We assessed for associations between CTC counts and the number and sites of metastatic disease. RESULTS CTC evaluations were carried out in 33 patients with metastatic UC. Fourteen of 33 patients (44%; 95% confidence interval 27% to 59%) had a positive assay (range 0-87 cells/7.5 ml of blood) with 10 patients (31%) having five or more CTCs. A significantly higher number of CTCs was seen in patients with two or more sites of metastases compared with those with less than one or one site of metastases (3.5 versus 0, P = 0.04). CONCLUSIONS CTCs, detected by antibody capture technology, are present in 44% of patients with metastatic UC. Higher numbers of CTCs are seen in patients with a greater number of metastatic sites. One-third of patients have five or more CTCs providing a potential early marker to monitor response to chemotherapy.

Phase II Study of Gemcitabine, Carboplatin, and Bevacizumab in Patients With Advanced Unresectable or Metastatic Urothelial Cancer

PURPOSE Although gemcitabine and carboplatin (GCa) is a standard option for patients with advanced urothelial cancer (UC) who are ineligible for cisplatin, outcomes remain poor. This trial evaluated the efficacy and safety of bevacizumab with GCa in advanced UC. PATIENTS AND METHODS Patients with Karnofsky performance status of 60% to 70%, creatinine clearance less than 60 mL/min, visceral metastasis, or solitary kidney were eligible and received a lead-in dose of bevacizumab 10 mg/kg followed 2 weeks later by gemcitabine 1,000 mg/m(2) on days 1 and 8 and carboplatin at area under the [concentration-time] curve (AUC) 5.0 or 4.5 and bevacizumab 15 mg/kg on day 1 every 21 days for six cycles. Patients achieving at least stable disease (SD) continued bevacizumab 15 mg/kg every 21 days for 18 additional cycles. The study was powered to detect a 50% improvement in median progression-free survival (PFS) over a historical control. RESULTS Fifty-one patients, median age 67 years (range, 42 to 83 years), were enrolled onto the study and were evaluable for toxicity. Twenty (39%) experienced grade 3 to 4 toxicity, and 10 (20%) had thromboembolic events (deep venous thrombosis or pulmonary embolism). Four received one or fewer cycles leaving 47 evaluable for outcomes. Twenty-three (49%) achieved response (three complete; 20 partial), and 11 had SD. Median PFS was 6.5 months (95% CI, 4.7 to 7.8 months); PFS was greater in the carboplatin AUC 5.0 group (P = .04). Median overall survival (OS) was 13.9 months. CONCLUSION The 95% one-sided lower confidence bound of 4.77 months for median PFS did not meet the predesignated PFS of more than 4.8 months considered sufficient for further study. Median OS was greater than expected. An ongoing phase III trial in patients who are eligible for therapy with cisplatin will define the role of bevacizumab in UC.

Sunitinib in urothelial cancer: clinical, pharmacokinetic, and immunohistochemical study of predictors of response.

BACKGROUND Sunitinib has activity in patients with metastatic urothelial cancer (UC), but most patients do not respond. OBJECTIVE To identify predictors of response to sunitinib. DESIGN, SETTING, AND PARTICIPANTS Seventy-seven patients with advanced UC received sunitinib on one of two schedules at a single institution. Blood pressure (BP), immunohistochemistry (IHC), and pharmacokinetic (PK) results were correlated with response to sunitinib. MEASUREMENTS BP was assessed on day 1 and 28 of each cycle and on day 14 of cycle 1. IHC was performed on 55 samples from 38 cases using mammalian target of rapamycin and hypoxia-inducible factor (HIF) pathway marker antibodies. Blood samples for PK analysis were collected from 15 patients at three time points. Response was assessed using Response Evaluation Criteria in Solid Tumors criteria. RESULTS AND LIMITATIONS Sunitinib-induced hypertension predicted improved response when hypertension was categorized as a discrete (p = 0.02) or continuous variable (p = 0.005 [systolic BP] and p = 0.007 [diastolic BP]). The odds ratio of response was 12.5 (95% confidence interval, 1.95-246.8) for grade 3/4 hypertension compared with grade 0. Response was associated with low HIF-1α expression in primary (p = 0.07) tissue. A nonstatistically significant trend was seen for an association between greater drug concentration and best response. A correlation between expression markers within the same pathways was identified, phosphorylated-4EBP1 and phosphorylated-S6 (p = 6.5 × 10(-9)), and vascular endothelial growth factor receptor 2 and HIF-1α (p = 0.008). Results are limited by small numbers. CONCLUSIONS Clinical and molecular biomarkers of response to sunitinib may have clinical relevance and require prospective validation. There is an urgent need for predictive biomarkers to guide the management of UC.