The potential of using circulating tumour cells and their gene expression to predict docetaxel response in metastatic prostate cancer.

Background: Docetaxel improves overall survival (OS) in castration-resistant prostate cancer (PCa) (CRPC) and metastatic hormone-sensitive PCa (mHSPC). However, not all patients respond due to inherent and/or acquired resistance. There remains an unmet clinical need for a robust predictive test to stratify patients for treatment. Liquid biopsy of circulating tumour cell (CTCs) is minimally invasive, can provide real-time information of the heterogeneous tumour and therefore may be a potentially ideal docetaxel response prediction biomarker. Objective: In this study we investigate the potential of using CTCs and their gene expression to predict post-docetaxel tumour response, OS and progression free survival (PFS). Methods: Peripheral blood was sampled from 18 mCRPC and 43 mHSPC patients, pre-docetaxel treatment, for CTC investigation. CTCs were isolated using the epitope independent Parsortix® system and gene expression was determined by multiplex RT-qPCR. We evaluated CTC measurements for post-docetaxel outcome prediction using receiver operating characteristics and Kaplan Meier analysis. Results: Detection of CTCs pre-docetaxel was associated with poor patient outcome post-docetaxel treatment. Combining total-CTC number with PSA and ALP predicted lack of partial response (PR) with an AUC of 0.90, p= 0.037 in mCRPC. A significantly shorter median OS was seen in mCRPC patients with positive CTC-score (12.80 vs. 37.33 months, HR= 5.08, p= 0.0005), ≥3 total-CTCs/7.5mL (12.80 vs. 37.33 months, HR= 3.84, p= 0.0053), ≥1 epithelial-CTCs/7.5mL (14.30 vs. 37.33 months, HR= 3.89, p= 0.0041) or epithelial to mesenchymal transitioning (EMTing)-CTCs/7.5mL (11.32 vs. 32.37 months, HR= 6.73, p= 0.0001). Significantly shorter PFS was observed in patients with ≥2 epithelial-CTCs/7.5mL (7.52 vs. 18.83 months, HR= 3.93, p= 0.0058). mHSPC patients with ≥5 CTCs/7.5mL had significantly shorter median OS (24.57 vs undefined months, HR= 4.14, p= 0.0097). In mHSPC patients, expression of KLK2, KLK4, ADAMTS1, ZEB1 and SNAI1 was significantly associated with shorter OS and/or PFS. Importantly, combining CTC measurements with clinical biomarkers increased sensitivity and specificity for prediction of patient outcome. Conclusion: While it is clear that CTC numbers and gene expression were prognostic for PCa post-docetaxel treatment, and CTC subtype analysis may have additional value, their potential predictive value for docetaxel chemotherapy response needs to be further investigated in large patient cohorts.

Phase 1, pharmacogenomic, dose-expansion study of pegargiminase plus pemetrexed and cisplatin in patients with ASS1-deficient non-squamous non-small cell lung cancer.

INTRODUCTION: We evaluated the arginine-depleting enzyme pegargiminase (ADI-PEG20; ADI) with pemetrexed (Pem) and cisplatin (Cis) (ADIPemCis) in ASS1-deficient non-squamous non-small cell lung cancer (NSCLC) via a phase 1 dose-expansion trial with exploratory biomarker analysis. METHODS: Sixty-seven chemonaïve patients with advanced non-squamous NSCLC were screened, enrolling 21 ASS1-deficient subjects from March 2015 to July 2017 onto weekly pegargiminase (36 mg/m2 ) with Pem (500 mg/m2 ) and Cis (75 mg/m2 ), every 3 weeks (four cycles maximum), with maintenance Pem or pegargiminase. Safety, pharmacodynamics, immunogenicity, and efficacy were determined; molecular biomarkers were annotated by next-generation sequencing and PD-L1 immunohistochemistry. RESULTS: ADIPemCis was well-tolerated. Plasma arginine and citrulline were differentially modulated; pegargiminase antibodies plateaued by week 10. The disease control rate was 85.7% (n = 18/21; 95% CI 63.7%-97%), with a partial response rate of 47.6% (n = 10/21; 95% CI 25.7%-70.2%). The median progression-free and overall survivals were 4.2 (95% CI 2.9-4.8) and 7.2 (95% CI 5.1-18.4) months, respectively. Two PD-L1-expressing (≥1%) patients are alive following subsequent pembrolizumab immunotherapy (9.5%). Tumoral ASS1 deficiency enriched for p53 (64.7%) mutations, and numerically worse median overall survival as compared to ASS1-proficient disease (10.2 months; n = 29). There was no apparent increase in KRAS mutations (35.3%) and PD-L1 (<1%) expression (55.6%). Re-expression of tumoral ASS1 was detected in one patient at progression (n = 1/3). CONCLUSIONS: ADIPemCis was safe and highly active in patients with ASS1-deficient non-squamous NSCLC, however, survival was poor overall. ASS1 loss was co-associated with p53 mutations. Therapies incorporating pegargiminase merit further evaluation in ASS1-deficient and treatment-refractory NSCLC.

Deferred Cytoreductive Nephrectomy Following Presurgical Vascular Endothelial Growth Factor Receptor-targeted Therapy in Patients with Primary Metastatic Clear Cell Renal Cell Carcinoma: A Pooled Analysis of Prospective Trial Data.

BACKGROUND: Cancer du Rein Métastatique Nephrectomie et Antiangiogéniques (CARMENA) concluded that sunitinib alone is not inferior to cytoreductive nephrectomy (CN) followed by vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs) in patients with metastatic renal cell carcinoma. It remains uncertain whether deferred CN is beneficial in this setting. OBJECTIVE: The aim of this study was to compare outcome in patients treated with presurgical VEGFR-TKI followed by CN (deferred CN) with that in patients receiving CN followed by VEGFR-TKI (upfront CN). DESIGN, SETTING, AND PARTICIPANTS: Pooled data from prospective trials in which a strategy of deferred CN in the absence of disease progression was investigated were compared with a retrospective dataset of upfront CN. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Overall survival (OS) in the Memorial Sloan-Kettering Cancer Center (MSKCC) intermediate-risk group. RESULTS AND LIMITATIONS: Patients were treated between 2006 and 2016. In the MSKCC intermediate-risk group, 144 patients with a strategy of deferred CN after systemic therapy were compared with 131 patients treated with upfront CN. OS in the deferred cohort was 33.0 mo (95% confidence interval [CI] 25.0-51.0) compared with 22.8 mo (95% CI 17.9-30.6) after upfront CN (hazard ratio 0.72 [95% CI 0.52-0.996], p = 0.047). This study is limited by retrospective comparison of data, subgroup analysis, and a lack of intention-to-treat data for the upfront CN cohort. CONCLUSIONS: In MSKCC intermediate-risk patients, a strategy of deferred CN in the absence of progression yields OS, which compares favourably with upfront CN and published trial data from CARMENA. This warrants a formal individual patient data analysis of CARMENA, SURTIME, and single-arm prospective studies to define the role and timing of deferred CN in intermediate-risk patients. PATIENT SUMMARY: In this study, we report outcomes in patients with metastatic renal cell cancer treated with targeted therapy followed by nephrectomy, which compared favourably with nephrectomy followed by targeted therapy and results from published studies.

Radiological Response Heterogeneity Is of Prognostic Significance in Metastatic Renal Cell Carcinoma Treated with Vascular Endothelial Growth Factor-targeted Therapy.

BACKGROUND: Response evaluation criteria in solid tumours (RECIST) is widely used to assess tumour response but is limited by not considering disease site or radiological heterogeneity (RH). OBJECTIVE: To determine whether RH or disease site has prognostic significance in patients with metastatic clear-cell renal cell carcinoma (ccRCC). DESIGN, SETTING, AND PARTICIPANTS: A retrospective analysis was conducted of a second-line phase II study in patients with metastatic ccRCC (NCT00942877), evaluating 138 patients with 458 baseline lesions. INTERVENTION: The phase II trial assessed vascular endothelial growth factor-targeted therapy±Src inhibition. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: RH at week 8 was assessed within individual patients with two or more lesions to predict overall survival (OS) using Kaplan-Meier method and Cox regression model. We defined a high heterogeneous response as occurring when one or more lesion underwent a ≥10% reduction and one or more lesion underwent a ≥10% increase in size. Disease progression was defined by RECIST 1.1 criteria. RESULTS AND LIMITATIONS: In patients with a complete/partial response or stable disease by RECIST 1.1 and two or more lesions at week 8, those with a high heterogeneous response had a shorter OS compared to those with a homogeneous response (hazard ratio [HR] 2.01; 95% confidence interval [CI]: 1.39-2.92; p<0.001). Response by disease site at week 8 did not affect OS. At disease progression, one or more new lesion was associated with worse survival compared with >20% increase in sum of target lesion diameters only (HR 2.12; 95% CI: 1.43-3.14; p<0.001). Limitations include retrospective study design. CONCLUSIONS: RH and the development of new lesions may predict survival in metastatic ccRCC. Further prospective studies are required. PATIENT SUMMARY: We looked at individual metastases in patients with kidney cancer and showed that a variable response to treatment and the appearance of new metastases may be associated with worse survival. Further studies are required to confirm these findings.

Response Rate to Chemotherapy After Immune Checkpoint Inhibition in Metastatic Urothelial Cancer.

Immune checkpoint inhibitors (ICIs) are active in metastatic urothelial carcinoma (MUC). They have joined chemotherapy (CT) as a standard of care. Here, we investigate the activity of CT after progression on ICIs. Two cohorts of sequential patients with MUC were described (n=28). Cohort A received first-line ICIs followed by CT after progression. Cohort B received CT after failure of first-line platinum-based CT followed by ICIs. Response rate (RR) to CT was assessed using Response Evaluation Criteria in Solid Tumors (RECIST v1.1) by a designated radiologist. Best RR for cohort A was 64%. Two patients experienced clinical progression and died before the first radiographic assessment. RR for cohort B was 21%, which was significantly lower than that for cohort A. Progression of disease occurred in 43% of cohort B patients by the end of CT. These data suggest a lack of cross resistance between CT and ICIs in MUC. Therefore, the sequencing of these drugs is likely to be important to maximise outcomes. This is particularly true after first-line ICIs as subsequent CT has significant activity. PATIENT SUMMARY: In this report, we studied the effect of chemotherapy in metastatic bladder cancer, which relapsed after immune checkpoint inhibitors. We found that the activity of chemotherapy was maintained despite previous exposure to immune therapy. This underlines the importance of sequencing these agents to maximise outcomes.

A Randomised Phase 2 Study of AZD2014 Versus Everolimus in Patients with VEGF-Refractory Metastatic Clear Cell Renal Cancer.

BACKGROUND: Everolimus is a mammalian target of rapamycin (mTOR) inhibitor used in vascular endothelial growth factor (VEGF)-refractory metastatic renal cell carcinoma (mRCC). It acts on only part of the mTOR complex (TORC1 alone). In vitro data support the use of mTOR inhibitors with broader activity (TORC1 and TORC2). OBJECTIVE: The purpose of this study was to determine whether combined TORC1 and TORC2 inhibition with AZD2014 has superior activity to everolimus in VEGF-refractory clear cell mRCC. DESIGN, SETTING, AND PARTICIPANTS: Patients with measurable mRCC and VEGF-refractory disease were eligible for this trial. INTERVENTION: Starting in February 2013, patients were randomised (1:1) to AZD2014 (50 mg twice daily) or everolimus (10 mg once daily) until progression of disease at 10 centres across the United Kingdom. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Progression-free survival (PFS) was the primary end point and was compared using the stratified log-rank test. Secondary end points included tolerability, response rates, overall survival (OS), and pharmacokinetics (PK) analysis. The study was planned to recruit 120 patients. RESULTS AND LIMITATIONS: Recruitment into the trial was stopped early (June 2014) due to lack of efficacy of AZD2014. At that point, 49 patients were randomised (26 to AZD2014 and 23 to everolimus). The PFS for AZD2014 and everolimus was 1.8 and 4.6 mo, respectively (hazard ratio: 2.8 [95% confidence interval (CI), 1.2-6.5]; p=0.01). Progression of disease as the best response to therapy was 69% for AZD2014 and 13% for everolimus (p<0.001). Grade 3-4 adverse events (AEs) occurred in 35% of AZD2014 and 48% of everolimus patients (p=0.3). Only 4% of patients stopped AZD2014 due to AEs. PK analysis suggested concentrations of AZD2014 were compatible with the therapeutic range. Final stratified OS hazard ratio at the time of trial closure (January 2015) was 3.1 (95% CI, 1.1-8.4; p<0.02). CONCLUSIONS: The PFS and OS of AZD2014 were inferior to everolimus in this setting despite acceptable AE and PK profiles. PATIENT SUMMARY: There is a strong rationale for testing mTOR inhibitors with a broader spectrum of activity than everolimus in metastatic clear cell renal cell carcinoma. AZD2014 is such an agent, but in this study, it was inferior to everolimus despite its attractive toxicity profile.

Safety and Efficacy of Pazopanib Therapy Prior to Planned Nephrectomy in Metastatic Clear Cell Renal Cancer.

IMPORTANCE: The role of cytoreductive nephrectomy in patients with metastatic renal cancer in the era of targeted therapy is uncertain. OBJECTIVE: To establish the safety and efficacy of upfront pazopanib therapy prior to cytoreductive nephrectomy in previously untreated patients with metastatic clear cell renal cancer. DESIGN, SETTING, AND PARTICIPANTS: Single-arm phase 2 study of 104 previously untreated patients with metastatic clear cell renal cancer recruited between June 2008 and October 2012 at cancer treatment centers with access to nephrectomy services. The minimum follow-up was 30 months. INTERVENTIONS: Patients received 12 to 14 weeks of preoperative pazopanib therapy prior to planned cytoreductive nephrectomy and continued pazopanib therapy after surgery. Treatment was stopped at disease progression. MAIN OUTCOMES AND MEASURES: The primary end point was clinical benefit (using Response Evaluation Criteria in Solid Tumors, version 1.1) prior to surgery (at 12-14 weeks). Secondary end points included surgical complications, progression-free survival (PFS), overall survival (OS), and biomarker analysis. RESULTS: Of 104 patients recruited, 100 patients were assessable for clinical benefit prior to planned nephrectomy; 80 of 104 (76.9%) were men; median [interquartile range] age, 64 [56-71] years). Overall, 84 of 100 (84% [95% CI, 75%-91%]) gained clinical benefit before planned nephrectomy. The median reduction in the size of the primary tumor was 14.4% (interquartile range, 1.4%-21.1%). No patients were unable to undergo surgery as a result of local progression of disease. Nephrectomy was performed in 63 (61%) of patients; 14 (22%) reported surgical complications. The 2 most common reasons for not undergoing surgery were progression of disease (n = 13) and patient choice (n = 9). There was 1 postoperative surgical death. The median PFS and OS for the whole cohort were 7.1 (95% CI, 6.0-9.2) and 22.7 (95% CI, 14.3-not estimable) months, respectively. Patients with MSKCC poor-risk disease or progressive disease prior to surgery had a poor outcome (median OS, 5.7 [95% CI, 2.6-10.8] and 3.9 [95% CI, 0.5-9.1] months, respectively). Surgical complications were observed in 14 (22%) of the nephrectomies. Biomarker analysis from sequential tissue samples revealed a decrease in CD8 expression (20.00 vs 13.75; P = .05) and significant reduction in expression of von Hippel-Lindau tumor suppressor (100 vs 40; P < .001) and C-MET (300 vs 100; P < .001) and increased programmed cell death ligand 1 expression (0 vs 1.5; P < .001) in the immune component. No on-treatment biomarker correlated with response. CONCLUSIONS AND RELEVANCE: Nephrectomy after upfront pazopanib therapy could be performed safely and was associated with good outcomes in patients with intermediate-risk metastatic clear cell renal cancer.

Patterns of Bladder Preservation Therapy Utilization for Muscle-Invasive Bladder Cancer.

Background: Trimodality bladder preservation therapy (BPT) in muscle invasive bladder cancer (MIBC) includes a maximal transurethral resection followed by concurrent chemoradiotherapy as an alternative to radical cystectomy (RC) in appropriately selected patients, or as a treatment option in non-cystectomy candidates. Several chemotherapy regimens can be used in BPT, but little is known about current practice patterns. Objective: To describe utilization patterns of BPT and associated survival outcomes in MIBC. Methods: Data were collected from the Retrospective International Study of Cancers of the Urothelial Tract (RISC), a database of 3,024 consecutive patients from 29 international academic centers from 2005 to 2013. Patients with clinical T2-T4aN0M0 urothelial cancer of the bladder were included. Results: 265 patients received BPT. Compared with the 1,447 patients who received RC, BPT patients were older, had poorer performance status, and had more comorbidities (p < 0.01 for all). Median overall survival (OS) was similar for patients treated with curative radiation doses in BPT and patients treated with RC (41 vs 46 months, p = 0.33, respectively). 45% of BPT patients received concurrent chemotherapy with radiation. The most common regimens included cisplatin alone (23%), carboplatin alone (22%), gemcitabine alone (10%), paclitaxel alone (9%), and 5-FU+mitomycin (5%). There were no significant differences in survival among chemotherapy regimens. Only 10 patients (4% of BPT patients) underwent salvage cystectomy. Conclusions: In clinical practice, BPT patients have similar survival to RC patients when treated with curative radiotherapy doses. Choice of concurrent chemotherapy regimen varied widely with no clear standard. Salvage cystectomy is rarely performed. Continued research is needed on the comparative effectiveness among BPT and RC, and among chemotherapy regimens in BPT.