Jean H. Hoffman-Censits

Atezolizumab in patients with locally advanced and metastatic urothelial carcinoma who have progressed following treatment with platinum-based chemotherapy: a single-arm, multicentre, phase 2 trial

BACKGROUND Patients with metastatic urothelial carcinoma have few treatment options after failure of platinum-based chemotherapy. In this trial, we assessed treatment with atezolizumab, an engineered humanised immunoglobulin G1 monoclonal antibody that binds selectively to programmed death ligand 1 (PD-L1), in this patient population. METHODS For this multicentre, single-arm, two-cohort, phase 2 trial, patients (aged ≥18 years) with inoperable locally advanced or metastatic urothelial carcinoma whose disease had progressed after previous platinum-based chemotherapy were enrolled from 70 major academic medical centres and community oncology practices in Europe and North America. Key inclusion criteria for enrolment were Eastern Cooperative Oncology Group performance status of 0 or 1, measurable disease defined by Response Evaluation Criteria In Solid Tumors version 1.1 (RECIST v1.1), adequate haematological and end-organ function, and no autoimmune disease or active infections. Formalin-fixed paraffin-embedded tumour specimens with sufficient viable tumour content were needed from all patients before enrolment. Patients received treatment with intravenous atezolizumab (1200 mg, given every 3 weeks). PD-L1 expression on tumour-infiltrating immune cells (ICs) was assessed prospectively by immunohistochemistry. The co-primary endpoints were the independent review facility-assessed objective response rate according to RECIST v1.1 and the investigator-assessed objective response rate according to immune-modified RECIST, analysed by intention to treat. A hierarchical testing procedure was used to assess whether the objective response rate was significantly higher than the historical control rate of 10% at an α level of 0·05. This study is registered with ClinicalTrials.gov, number NCT02108652. FINDINGS Between May 13, 2014, and Nov 19, 2014, 486 patients were screened and 315 patients were enrolled into the study. Of these patients, 310 received atezolizumab treatment (five enrolled patients later did not meet eligibility criteria and were not dosed with study drug). The PD-L1 expression status on infiltrating immune cells (ICs) in the tumour microenvironment was defined by the percentage of PD-L1-positive immune cells: IC0 (<1%), IC1 (≥1% but <5%), and IC2/3 (≥5%). The primary analysis (data cutoff May 5, 2015) showed that compared with a historical control overall response rate of 10%, treatment with atezolizumab resulted in a significantly improved RECIST v1.1 objective response rate for each prespecified immune cell group (IC2/3: 27% [95% CI 19-37], p<0·0001; IC1/2/3: 18% [13-24], p=0·0004) and in all patients (15% [11-20], p=0·0058). With longer follow-up (data cutoff Sept 14, 2015), by independent review, objective response rates were 26% (95% CI 18-36) in the IC2/3 group, 18% (13-24) in the IC1/2/3 group, and 15% (11-19) overall in all 310 patients. With a median follow-up of 11·7 months (95% CI 11·4-12·2), ongoing responses were recorded in 38 (84%) of 45 responders. Exploratory analyses showed The Cancer Genome Atlas (TCGA) subtypes and mutation load to be independently predictive for response to atezolizumab. Grade 3-4 treatment-related adverse events, of which fatigue was the most common (five patients [2%]), occurred in 50 (16%) of 310 treated patients. Grade 3-4 immune-mediated adverse events occurred in 15 (5%) of 310 treated patients, with pneumonitis, increased aspartate aminotransferase, increased alanine aminotransferase, rash, and dyspnoea being the most common. No treatment-related deaths occurred during the study. INTERPRETATION Atezolizumab showed durable activity and good tolerability in this patient population. Increased levels of PD-L1 expression on immune cells were associated with increased response. This report is the first to show the association of TCGA subtypes with response to immune checkpoint inhibition and to show the importance of mutation load as a biomarker of response to this class of agents in advanced urothelial carcinoma. FUNDING F Hoffmann-La Roche Ltd.

Identification of Distinct Basal and Luminal Subtypes of Muscle-Invasive Bladder Cancer with Different Sensitivities to Frontline Chemotherapy

Muscle-invasive bladder cancers (MIBCs) are biologically heterogeneous and have widely variable clinical outcomes and responses to conventional chemotherapy. We discovered three molecular subtypes of MIBC that resembled established molecular subtypes of breast cancer. Basal MIBCs shared biomarkers with basal breast cancers and were characterized by p63 activation, squamous differentiation, and more aggressive disease at presentation. Luminal MIBCs contained features of active PPARγ and estrogen receptor transcription and were enriched with activating FGFR3 mutations and potential FGFR inhibitor sensitivity. p53-like MIBCs were consistently resistant to neoadjuvant methotrexate, vinblastine, doxorubicin and cisplatin chemotherapy, and all chemoresistant tumors adopted a p53-like phenotype after therapy. Our observations have important implications for prognostication, the future clinical development of targeted agents, and disease management with conventional chemotherapy.

Defects in DNA Repair Genes Predict Response to Neoadjuvant Cisplatin-based Chemotherapy in Muscle-invasive Bladder Cancer

BACKGROUND Cisplatin-based neoadjuvant chemotherapy (NAC) before cystectomy is the standard of care for muscle-invasive bladder cancer (MIBC), with 25-50% of patients expected to achieve a pathologic response. Validated biomarkers predictive of response are currently lacking. OBJECTIVE To discover and validate biomarkers predictive of response to NAC for MIBC. DESIGN, SETTING, AND PARTICIPANTS Pretreatment MIBC samples prospectively collected from patients treated in two separate clinical trials of cisplatin-based NAC provided the discovery and validation sets. DNA from pretreatment tumor tissue was sequenced for all coding exons of 287 cancer-related genes and was analyzed for base substitutions, indels, copy number alterations, and selected rearrangements in a Clinical Laboratory Improvements Amendments-certified laboratory. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The mean number of variants and variant status for each gene were correlated with response. Variant data from the discovery cohort were used to create a classification tree to discriminate responders from nonresponders. The resulting decision rule was then tested in the independent validation set. RESULTS AND LIMITATIONS Patients with a pathologic complete response had more alterations than those with residual tumor in both the discovery (p=0.024) and validation (p=0.018) sets. In the discovery set, alteration in one or more of the three DNA repair genes ATM, RB1, and FANCC predicted pathologic response (p<0.001; 87% sensitivity, 100% specificity) and better overall survival (p=0.007). This test remained predictive for pathologic response in the validation set (p=0.033), with a trend towards better overall survival (p=0.055). These results require further validation in additional sample sets. CONCLUSIONS Genomic alterations in the DNA repair-associated genes ATM, RB1, and FANCC predict response and clinical benefit after cisplatin-based chemotherapy for MIBC. The results suggest that defective DNA repair renders tumors sensitive to cisplatin. PATIENT SUMMARY Chemotherapy given before bladder removal (cystectomy) improves the chance of cure for some but not all patients with muscle-invasive bladder cancer. We found a set of genetic mutations that when present in tumor tissue predict benefit from neoadjuvant chemotherapy, suggesting that testing before chemotherapy may help in selecting patients for whom this approach is recommended.

Accelerated Methotrexate, Vinblastine, Doxorubicin, and Cisplatin Is Safe, Effective, and Efficient Neoadjuvant Treatment for Muscle-Invasive Bladder Cancer: Results of a Multicenter Phase II Study With Molecular Correlates of Response and Toxicity

PURPOSE Neoadjuvant cisplatin-based chemotherapy is standard of care for muscle-invasive bladder cancer (MIBC); however, it is infrequently adopted in practice because of concerns regarding toxicity and delay to cystectomy. We hypothesized that three cycles of neoadjuvant accelerated methotrexate, vinblastine, doxorubicin, and cisplatin (AMVAC) would be safe, shorten the time to surgery, and yield similar pathologic complete response (pT0) rates compared with historical controls. PATIENTS AND METHODS Patients with cT2-T4a and N0-N1 MIBC were eligible and received three cycles of AMVAC with pegfilgrastim followed by radical cystectomy with lymph node dissection. The primary end point was pT0 rate. Telomere length (TL) and p53 mutation status were correlated with response and toxicity. RESULTS Forty-four patients were accrued; 60% had stage III to IV disease; median age was 64 years. Forty patients were evaluable for response, with 15 (38%; 95% CI, 23% to 53%) showing pT0 at cystectomy, meeting the primary end point of the study. Another six patients (14%) were downstaged to non-muscle invasive disease. Most (82%) experienced only grade 1 to 2 treatment-related toxicities. There were no grade 3 or 4 renal toxicities and no treatment-related deaths. One patient developed metastases and thus did not undergo cystectomy; all others (n = 43) proceeded to cystectomy within 8 weeks after last chemotherapy administration. Median time from start of chemotherapy to cystectomy was 9.7 weeks. TL and p53 mutation did not predict response or toxicity. CONCLUSION AMVAC is well tolerated and results in similar pT0 rates with 6 weeks of treatment compared with standard 12-week regimens. Further analysis is ongoing to ascertain whether molecular alterations in tumor samples can predict response to chemotherapy.

Enhancing Prostate Cancer Care Through the Multidisciplinary Clinic Approach: A 15-Year Experience

PURPOSE To report on the 15-year prostate cancer experience of our multidisciplinary genitourinary cancer clinic established in 1996 at the National Cancer Institute (NCI) -designated Jefferson Kimmel Cancer Center. Patients with genitourinary cancers were evaluated weekly by multiple specialists at a single site, and we focus on the 83% of patients with prostate cancer. To our knowledge, our multidisciplinary genitourinary cancer clinic is the longest continuously operating center of its kind at an NCI Cancer Center in the United States. METHODS Data from Jeffersons Oncology Data Services were compared to SEER prostate cancer outcomes. Data on treatment changes in localized disease, patient satisfaction, and related parameters were also assessed. RESULTS Ten-year survival data approach 100% in stage I and II prostate cancer. Ten-year data for stage III (T3 N0M0) and stage IV (T4 N0M0) disease show that our institutional survival rate exceeds SEER. There is a shift toward robotically assisted laparoscopic radical prostatectomy and a slight decrease in brachytherapy relative to external beam radiation therapy in localized disease. Patient satisfaction is high as measured by survey instruments. CONCLUSION Our long-term experience suggests a benefit of the multidisciplinary clinic approach to prostate cancer, most pronounced for high-risk, locally advanced disease. A high level of satisfaction with this patient-centered model is seen. The multidisciplinary clinic approach to prostate cancer may enhance outcomes and possibly reduce treatment regret through a coordinated presentation of all therapeutic options. This clinic model serves as an interdisciplinary educational tool for patients, their families, and our trainees and supports clinical trial participation.

Physician Beliefs and Practices for Adjuvant and Salvage Radiation Therapy After Prostatectomy

PURPOSE Despite results of randomized trials that support adjuvant radiation therapy (RT) after radical prostatectomy (RP) for prostate cancer with adverse pathologic features (APF), many clinicians favor selective use of salvage RT. This survey was conducted to evaluate the beliefs and practices of radiation oncologists (RO) and urologists (U) regarding RT after RP. METHODS AND MATERIALS We designed a Web-based survey of post-RP RT beliefs and policies. Survey invitations were e-mailed to a list of 926 RO and 591 U. APF were defined as extracapsular extension, seminal vesicle invasion, or positive surgical margin. Differences between U and RO in adjuvant RT recommendations were evaluated by comparative statistics. Multivariate analyses were performed to evaluate factors predictive of adjuvant RT recommendation. RESULTS Analyzable surveys were completed by 218 RO and 92 U (overallresponse rate, 20%). Adjuvant RT was recommended based on APF by 68% of respondents (78% RO, 44% U, p <0.001). U were less likely than RO to agree that adjuvant RT improves survival and/or biochemical control (p < 0.0001). PSA thresholds for salvage RT were higher among U than RO (p < 0.001). Predicted rates of erectile dysfunction due to RT were higher among U than RO (p <0.001). On multivariate analysis, respondent specialty was the only predictor of adjuvant RT recommendations. CONCLUSIONS U are less likely than RO to recommend adjuvant RT. Future research efforts should focus on defining the toxicities of post-RP RT and on identifying the subgroups of patients who will benefit from adjuvant vs. selective salvage RT.

Chemotherapy for Penile and Urethral Carcinoma

Although surgery is the mainstay of curative treatment of carcinomas of the penis and urethra, there is a role for systemic cytotoxic chemotherapy for locally advanced, unresectable, or metastatic tumors. Although this field is limited by a paucity of clinical trials or prospective data, the available single institutional retrospective reviews indicate that multi-agent cisplatin-based combination chemotherapy regimens have significant activity and may allow curative surgery for patients with otherwise unresectable tumors. Toxicity remains a concern in this typically older patient population, and clearly new regimens are necessary. This article reviews the available literature on chemotherapy for carcinoma of the penis and urethra in the neoadjuvant, adjuvant, and metastatic setting.

Hematologic Toxicity of Concurrent Administration of Radium-223 and Next-generation Antiandrogen Therapies

Purpose/Objectives: Radium-223 is a first-in-class radiopharmaceutical recently approved for the treatment of castration-resistant prostate cancer in patients with symptomatic bone metastases. Initial studies investigating Radium-223 primarily used nonsteroidal first-generation antiandrogens. Since that time, newer antiandrogen therapies have demonstrated improved survival in patients with castration-resistant prostate cancer. It has been suggested that the rational combination of these newly approved agents with Radium-223 may lead to improved response rates and clinical outcomes. Currently, there is lack of information regarding the safety of concurrent administration of these agents with radiopharmaceuticals. Here, we report on hematologic toxicity findings from our institution in patients receiving concurrent Radium-223 and next-generation antiandrogen therapies with either enzalutamide or abiraterone. Materials/Methods: In a retrospective study, we analyzed patients who received Radium-223 as part of an early-access trial, and following FDA approval in May 2013, patients receiving Radium-223 as part of standard care. Radium-223 was given at standard dosing of 50 kBq/kg each month for 6 total cycles. Complete blood counts were performed before treatment monthly and following each injection. Blood counts from patients receiving Radium alone and concurrently with next-generation antiandrogens were compared. To date, 25 total patients were analyzed, with a median of 5 monthly doses received per patient. Fourteen patients received concurrent therapy during monthly Radium-223 with either enzalutamide (n=8) or abiraterone (n=6). Results: Six patients expired due to disease progression. Two patients discontinued treatment due to grade 3 myelosuppression. For patients receiving either Radium alone and with concurrent next-generation antiandrogen therapy, there did not appear to be any statistically significant differences between initial and nadir blood counts. Mean change from initial neutrophil count to nadir was 1.9×106/L in patients receiving Radium alone, versus 2.3×106/L in patients receiving concurrent therapy (P=0.77). Mean change from initial hemoglobin value to nadir was 1.5 g/L in patients receiving Radium alone, versus 1.8 g/L in patients receiving concurrent therapy (P=0.31). Mean change from initial platelet count to nadir was 52.3×109 cells/L in patients receiving Radium alone versus 70.6×109 cells/L in patients receiving concurrent therapy (P=0.39). Individual blood counts for each measured laboratory are included in the supplemental data. PSA was stable or decreased in 22% of patients receiving Radium alone versus 35% of patients receiving combination treatment (P=0.24). Conclusions: Concurrent administration of Radium-223 and next-generation antiandrogen therapies appears to be well tolerated with similar toxicities to standard administration of Radium-223 alone. This particular cohort of patients represents a high-risk, heavily pretreated group of patients with advanced metastatic disease and significant marrow burden. Despite these risk factors, hematologic toxicity was modest and was in the range expected for this risk group based on previous trials. To date, this is the first study investigating the toxicity of combination treatment. Further studies investigating the safety and efficacy of combination treatments are warranted.

Atezolizumab in platinum-treated locally advanced or metastatic urothelial carcinoma: post-progression outcomes from the phase II IMvigor210 study

Background Conventional criteria for tumor progression may not fully reflect the clinical benefit of immunotherapy or appropriately guide treatment decisions. The phase II IMvigor210 study demonstrated the efficacy and safety of atezolizumab, a programmed death-ligand 1-directed antibody, in patients with platinum-treated locally advanced or metastatic urothelial carcinoma. Patients could continue atezolizumab beyond Response Evaluation Criteria In Solid Tumors (RECIST) v1.1 progression at the investigators discretion: this analysis assessed post-progression outcomes in these patients. Patients and methods Patients were treated with atezolizumab 1200 mg i.v. every 3 weeks until loss of clinical benefit. Efficacy and safety outcomes in patients who experienced RECIST v1.1 progression and did, or did not, continue atezolizumab were analyzed descriptively. Results In total, 220 patients who experienced progression from the overall cohort (n = 310) were analyzed: 137 continued atezolizumab for ≥ 1 dose after progression, 19 received other systemic therapy, and 64 received no further systemic therapy. Compared with those who discontinued, patients continuing atezolizumab beyond progression were more likely to have had a baseline Eastern Cooperative Oncology Group performance status of 0 (43.1% versus 31.3%), less likely to have had baseline liver metastases (27.0% versus 41.0%), and more likely to have had an initial response to atezolizumab (responses in 11.7% versus 1.2%). Five patients (3.6%) continuing atezolizumab after progression had subsequent responses compared with baseline measurements. Median post-progression overall survival was 8.6 months in patients continuing atezolizumab, 6.8 months in those receiving another treatment, and 1.2 months in those receiving no further treatment. Atezolizumab exposure-adjusted adverse event frequencies were generally similar before and following progression. Conclusion In this single-arm study, patients who continued atezolizumab beyond RECIST v1.1 progression derived prolonged clinical benefit without additional safety signals. Identification of patients most likely to benefit from atezolizumab beyond progression remains an important challenge in the management of metastatic urothelial carcinoma. ClinicalTrials.gov ID NCT02108652.

Chemotherapy and Targeted Therapies: Are We Making Progress in Castrate-Resistant Prostate Cancer?

First-line therapy for men with metastatic or recurrent prostate cancer following definitive local therapy is medical or surgical castration. Though effective initially in most patients, the majority of tumors develop castration resistance, necessitating the addition of further therapy. The historic treatment paradigm of second-line androgen manipulation, followed by cytotoxic salvage chemotherapy, has changed in recent years with better understanding of mechanisms that lead to castration resistance. This review will outline the data supporting the use of targeted and chemotherapeutic agents for prostate cancer, review data leading to US Food and Drug Administration (FDA) approval of the newest agents abiraterone, enzalutamide, and cabazitaxel, as well as review ongoing studies of novel agents.