PET/CT scan and biopsy-driven approach for safe anti-PD-1 therapy discontinuation in patients with advanced melanoma.

BACKGROUND: Limited data exist on safe discontinuation of antiprogrammed cell death protein 1 (PD-1) therapy in responding patients with advanced melanoma. The use of 18fluorodeoxyglucose (18FDG)-PET/CT scan and tumor biopsy for assessment of active disease may be an effective predictive biomarker to guide such treatment decisions. METHODS: A retrospective study of 122 patients with advanced melanoma treated with anti-PD-1 monotherapy or anti-PD-1/anticytotoxic T-lymphocyte-associated protein 4 combination therapy at Georgetown Lombardi Comprehensive Cancer Center was conducted. Uveal melanoma patients and those receiving concurrent experimental therapy were excluded. Baseline characteristics, treatment outcomes, and survival were analyzed. Patients who decided to come off treatment typically after 12 months using CT scan radiographic complete response (CR), 18FDG-PET/CT scan complete metabolic response (CMR) or tumor biopsy of a non-CR/CMR tumor site negative for active disease (possible pathological CR) were identified and compared with patients who discontinued treatment due to toxicity while their disease was in control. Event-free survival (EFS) was assessed from the last dose of anti-PD-1 therapy to progression requiring subsequent treatment (surgery, radiation, and/or systemic therapy) or referral to hospice/death due to melanoma. RESULTS: 24 (20%) patients discontinued treatment by choice with no active disease and 28 (23%) patients discontinued treatment due to toxicity with disease control after 12-month and 4-month median treatment durations, respectively. Similar baseline characteristics were observed between cohorts except higher prior receipt of ipilimumab (29% vs 7%; p=0.036) and fewer BRAF mutant positive disease (17% vs 41%; p=0.064) in patients off treatment by choice. Three-year EFS rates were 95% and 71%, respectively. No significant associations between EFS and sex, disease stage, lactate dehydrogenase elevation, BRAF status, prior systemic therapy, ECOG performance status, presence of brain metastases, or combination versus monotherapy were observed. Tumor biopsies led to alternative management in 3/10 patients due to active metastatic melanoma or second malignancy. CONCLUSIONS: Anti-PD-1 therapy discontinuation after 12 months when no active disease is observed on CT scan, PET/CT scan or tumor biopsy may have low rates of disease relapse in patients with advanced melanoma. Biopsy of residual disease may frequently lead to a change in management. These findings are undergoing validation in the EA6192 trial.

Arterial Spin Labeled Perfusion MRI for the Evaluation of Response to Tyrosine Kinase Inhibition Therapy in Metastatic Renal Cell Carcinoma.

Background Tumor perfusion may inform therapeutic response and resistance in metastatic renal cell carcinoma (RCC) treated with antiangiogenic therapy. Purpose To determine if arterial spin labeled (ASL) MRI perfusion changes are associated with tumor response and disease progression in metastatic RCC treated with vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs). Materials and Methods In this prospective study (ClinicalTrials.gov identifier: NCT00749320), metastatic RCC perfusion was measured with ASL MRI before and during sunitinib or pazopanib therapy between October 2008 and March 2014. Objective response rate (ORR) and progression-free survival (PFS) were calculated. Perfusion was compared between responders and nonresponders at baseline, at week 2, after cycle 2 (12 weeks), after cycle 4 (24 weeks), and at disease progression and compared with the ORR by using the Wilcoxon rank sum test and with PFS by using the log-rank test. Results Seventeen participants received sunitinib (mean age, 59 years ± 7.0 [standard deviation]; 11 men); 11 participants received pazopanib (mean age, 63 years ± 6.6; eight men). Responders had higher baseline tumor perfusion than nonresponders (mean, 404 mL/100 g/min ± 213 vs 199 mL/100 g/min ± 136; P = .02). Perfusion decreased from baseline to week 2 (-53 mL/100 g/min ± 31; P < .001), after cycle 2 (-65 mL/100 g/min ± 25; P < .001), and after cycle 4 (-79 mL/100 g/min ± 15; P = .008). Interval reduction in perfusion at those three time points was not associated with ORR (P = .63, .29, and .27, respectively) or PFS (P = .28, .27, and .32). Perfusion increased from cycle 4 to disease progression (51% ± 11; P < .001). Conclusion Arterial spin labeled perfusion MRI may assist in identifying responders to vascular endothelial growth factor receptor tyrosine kinase inhibitors and may help detect early evidence of disease progression in patients with metastatic renal cell carcinoma. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Goh and De Vita in this issue.

Final Overall Survival Results from a Phase 3 Study to Compare Tivozanib to Sorafenib as Third- or Fourth-line Therapy in Subjects with Metastatic Renal Cell Carcinoma.

Tivozanib is a potent and selective inhibitor of the VEGF receptor. In an open-label, randomized phase 3 trial, we compared tivozanib to sorafenib in patients with metastatic renal cell carcinoma (mRCC) who had received two or three prior therapies. We have previously reported that the study met its primary endpoint, demonstrating an improvement in progression-free survival with tivozanib versus sorafenib (5.6 mo vs 3.9 mo; hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.56-0.94; p=0.016). The current report reflects the final assessment of overall survival, showing no difference between treatment with tivozanib and sorafenib (HR 0.97, 95% CI 0.75-1.24). Given its activity and distinct tolerability profile, tivozanib represents a treatment option for patients with previously treated mRCC. PATIENT SUMMARY: We show that tivozanib, a targeted therapy, can delay tumor growth relative to an already approved targeted therapy (sorafenib) in patients with kidney cancer who have received two or three prior treatments. No difference in survival was observed.

Patient-Reported Outcomes from the Phase III Randomized IMmotion151 Trial: Atezolizumab + Bevacizumab versus Sunitinib in Treatment-Naïve Metastatic Renal Cell Carcinoma.

PURPOSE: Patient-reported outcomes (PRO) were evaluated in the phase III IMmotion151 trial (NCT02420821) to inform overall treatment/disease burden of atezolizumab plus bevacizumab versus sunitinib in patients with previously untreated metastatic renal cell carcinoma (mRCC). PATIENTS AND METHODS: Patients were randomized 1:1 to receive atezolizumab 1,200 mg intravenous (i.v.) infusions every 3 weeks (q3w) plus bevacizumab 15 mg/kg i.v. q3w or sunitinib 50 mg per day orally 4 weeks on/2 weeks off. Patients completed the MD Anderson Symptom Inventory (MDASI), National Comprehensive Cancer Network Functional Assessment of Cancer Therapy-Kidney Symptom Index (FKSI-19), and Brief Fatigue Inventory (BFI) at baseline, q3w during treatment, at end of treatment, and during survival follow-up. Longitudinal and time to deterioration (TTD) analyses for core and RCC symptoms and their interference with daily life, treatment side-effect bother, and health-related quality of life (HRQOL) were evaluated. RESULTS: The intent-to-treat population included 454 and 461 patients in the atezolizumab plus bevacizumab and sunitinib arms, respectively. Completion rates for each instrument were 83% to 86% at baseline and ≥ 70% through week 54. Milder symptoms, less symptom interference and treatment side-effect bother, and better HRQOL at most visits were reported with atezolizumab plus bevacizumab versus sunitinib. The TTD HR (95% CI) favored atezolizumab plus bevacizumab for core (HR, 0.50; 0.40-0.62) and RCC symptoms (HR, 0.45; 0.37-0.55), symptom interference (HR, 0.56; 0.46-0.68), and HRQOL (HR, 0.68; 0.58-0.81). CONCLUSIONS: PROs in IMmotion151 suggest lower overall treatment burden with atezolizumab plus bevacizumab compared with sunitinib in patients with treatment-naïve mRCC and provide further evidence for clinical benefit of this regimen.

Tivozanib versus sorafenib in patients with advanced renal cell carcinoma (TIVO-3): a phase 3, multicentre, randomised, controlled, open-label study.

BACKGROUND: Treatment for renal cell carcinoma has been revolutionised by inhibitors of VEGF receptor. Previous studies have suggested that treatment with a VEGF receptor (VEGFR) tyrosine kinase inhibitor might be effective in patients who had previous checkpoint inhibitor therapy. Therefore, TIVO-3 was designed to compare the efficacy and safety of tivozanib (a potent and selective VEGFR inhibitor) with those of sorafenib as third-line or fourth-line therapy in patients with metastatic renal cell carcinoma. METHODS: In this open-label, randomised, controlled trial done at 120 academic hospitals in 12 countries, we enrolled eligible patients older than 18 years with histologically or cytologically confirmed metastatic renal cell carcinoma and at least two previous systemic treatments (including at least one previous treatment with a VEGFR inhibitor), measurable disease according to the Response Evaluation Criteria in Solid Tumors version 1.1, and an Eastern Cooperative Oncology Group performance status of 0 or 1. Patients were excluded if they had received previous treatment with tivozanib or sorafenib. Patients were stratified by International Metastatic Renal Cell Carcinoma Database Consortium risk category and type of previous therapy and randomised (1:1) with a complete permuted block design (block size of four) to either tivozanib 1·5 mg orally once daily in 4-week cycles or sorafenib 400 mg orally twice daily continuously. Investigators and patients were not masked to treatment. The primary endpoint was progression-free survival by independent review in the intention-to-treat population. Safety analyses were done in all patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, NCT02627963. FINDINGS: Between May 24, 2016, and Aug 14, 2017, 350 patients were randomly assigned to receive tivozanib (175 patients) or sorafenib (175 patients). Median follow-up was 19·0 months (IQR 15·0-23·4). Median progression-free survival was significantly longer with tivozanib (5·6 months, 95% CI 5·29-7·33) than with sorafenib (3·9 months, 3·71-5·55; hazard ratio 0·73, 95% CI 0·56-0·94; p=0·016). The most common grade 3 or 4 treatment-related adverse event was hypertension (35 [20%] of 173 patients treated with tivozanib and 23 [14%] of 170 patients treated with sorafenib). Serious treatment-related adverse events occurred in 19 (11%) patients with tivozanib and in 17 (10%) patients with sorafenib. No treatment-related deaths were reported. INTERPRETATION: Our study showed that tivozanib as third-line or fourth-line therapy improved progression-free survival and was better tolerated compared with sorafenib in patients with metastatic renal cell carcinoma. FUNDING: AVEO Oncology.

Angiogenic Factor and Cytokine Analysis among Patients Treated with Adjuvant VEGFR TKIs in Resected Renal Cell Carcinoma.

PURPOSE: The use of VEGFR TKIs for the adjuvant treatment of renal cell carcinoma (RCC) remains controversial. We investigated the effects of adjuvant VEGFR TKIs on circulating cytokines in the ECOG-ACRIN 2805 (ASSURE) trial. EXPERIMENTAL DESIGN: Patients with resected high-risk RCC were randomized to sunitinib, sorafenib, or placebo. Plasma from 413 patients was analyzed from post-nephrectomy baseline, 4 weeks, and 6 weeks after treatment initiation. Mixed effects and Cox proportional hazards models were used to test for changes in circulating cytokines and associations between disease-free survival (DFS) and cytokine levels. RESULTS: VEGF and PlGF increased after 4 weeks on sunitinib or sorafenib (P < 0.0001 for both) and returned to baseline at 6 weeks on sunitinib (corresponding to the break in the sunitinib schedule) but not sorafenib (which was administered continuously). sFLT-1 decreased after 4 weeks on sunitinib and 6 weeks on sorafenib (P < 0.0001). sVEGFR-2 decreased after both 4 and 6 weeks of treatment on sunitinib or sorafenib (P < 0.0001). Patients receiving placebo had no significant changes in cytokine levels. CXCL10 was elevated at 4 and 6 weeks on sunitinib and sorafenib but not on placebo. Higher baseline CXCL10 was associated with worse DFS (HR 1.41 per log increase in CXCL10, Bonferroni-adjusted P = 0.003). This remained significant after adjustment for T-stage, Fuhrman grade, and ECOG performance status. CONCLUSIONS: Among patients treated with adjuvant VEGFR TKIs for RCC, drug-host interactions mediate changes in circulating cytokines. Elevated baseline CXCL10 was associated with worse DFS. Studies to understand functional consequences of these changes are under way.

Adjuvant Treatment for High-Risk Clear Cell Renal Cancer: Updated Results of a High-Risk Subset of the ASSURE Randomized Trial.

IMPORTANCE: Given recently published results of a 750-patient adjuvant sunitinib trial showing improved disease-free survival (DFS), the appropriate strategy for treating high-risk patients is unclear. We sought to determine whether there is improved disease-free survival benefit to taking the active drug in patients with high-risk (pT3, pT4, node-positive) clear cell renal cancer (ccRCC) in the ASSURE trial (adjuvant sunitinib or sorafenib vs placebo in resected unfavorable renal cell carcinoma [RCC]), the largest adjuvant trial published to date. OBJECTIVE: To evaluate DFS and overall survival (OS) in ccRCC high-risk patients randomized to sunitinib or sorafenib vs placebo among patients with stages comparable to other high-risk adjuvant trials. DESIGN, SETTING, AND PARTICIPANTS: The DFS and OS at 10 years postactivation were calculated for 1069 patients in US and Canadian cooperative groups with high-risk patients who had ccRCC histology and pT3, pT4, or node-positive disease accrued between 2006 and 2010 to the double-blind randomized placebo-controlled phase 3 trial. Outcome analyses by dose quartiles of these patients receiving sunitinib or sorafenib were also performed. INTERVENTIONS: Patients received 1 year of adjuvant sunitinib (50 mg), sorafenib (800 mg) daily, or equivalent placebo. The study was amended for patient intolerance to sunitinib (37.5 mg), sorafenib (400 mg) daily, or equivalent placebo with mandatory dose escalation if no serious adverse effects were experienced. MAIN OUTCOMES AND MEASURES: Disease-free survival, defined as time from randomization to recurrence, second primary cancer, or death. RESULTS: Of 1069 patients, 358 (243 [67.9%] men, 115 [32.1%] women) received sunitinib, 355 (248 [69.9%] men, 107 [30.1%] women) received sorafenib, and 356 (254 [71.3%] men, 102 [28.7%] women) received placebo as adjuvant therapy. The mean (SD) age for each group was 58.3 (10.6) years, 56.8 (10.3) years, and 57.5 (10.4) years, respectively. Five-year DFS rates were 47.7%, 49.9%, and 50.0%, respectively for sunitinib, sorafenib, and placebo (HR, 0.94 for sunitinib vs placebo; and HR, 0.90; 97.5% CI, 0.71-1.14 for sorafenib vs placebo), with 5-year OS of 75.2%, 80.2%, and 76.5% (HR, 1.06; 97.5% CI, 0.78-1.45; P = .66, sunitinib vs placebo; and HR, 0.80; 97.5% CI, 0.58-1.11; P = .12 for sorafenib vs placebo). There was no difference by dose quartile. CONCLUSIONS AND RELEVANCE: Neither prognostic category of the tumor nor dose intensity of therapy altered the lack of difference in DFS or OS in this population of patients with high-risk ccRCC. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00326898.

Adjuvant sunitinib or sorafenib for high-risk, non-metastatic renal-cell carcinoma (ECOG-ACRIN E2805): a double-blind, placebo-controlled, randomised, phase 3 trial.

BACKGROUND: Renal-cell carcinoma is highly vascular, and proliferates primarily through dysregulation of the vascular endothelial growth factor (VEGF) pathway. We tested sunitinib and sorafenib, two oral anti-angiogenic agents that are effective in advanced renal-cell carcinoma, in patients with resected local disease at high risk for recurrence. METHODS: In this double-blind, placebo-controlled, randomised, phase 3 trial, we enrolled patients at 226 study centres in the USA and Canada. Eligible patients had pathological stage high-grade T1b or greater with completely resected non-metastatic renal-cell carcinoma and adequate cardiac, renal, and hepatic function. Patients were stratified by recurrence risk, histology, Eastern Cooperative Oncology Group (ECOG) performance status, and surgical approach, and computerised double-blind randomisation was done centrally with permuted blocks. Patients were randomly assigned (1:1:1) to receive 54 weeks of sunitinib 50 mg per day orally throughout the first 4 weeks of each 6 week cycle, sorafenib 400 mg twice per day orally throughout each cycle, or placebo. Placebo could be sunitinib placebo given continuously for 4 weeks of every 6 week cycle or sorafenib placebo given twice per day throughout the study. The primary objective was to compare disease-free survival between each experimental group and placebo in the intention-to-treat population. All treated patients with at least one follow-up assessment were included in the safety analysis. This trial is registered with ClinicalTrials.gov, number NCT00326898. FINDINGS: Between April 24, 2006, and Sept 1, 2010, 1943 patients from the National Clinical Trials Network were randomly assigned to sunitinib (n=647), sorafenib (n=649), or placebo (n=647). Following high rates of toxicity-related discontinuation after 1323 patients had enrolled (treatment discontinued by 193 [44%] of 438 patients on sunitinib, 199 [45%] of 441 patients on sorafenib), the starting dose of each drug was reduced and then individually titrated up to the original full doses. On Oct 16, 2014, because of low conditional power for the primary endpoint, the ECOG-ACRIN Data Safety Monitoring Committee recommended that blinded follow-up cease and the results be released. The primary analysis showed no significant differences in disease-free survival. Median disease-free survival was 5·8 years (IQR 1·6-8·2) for sunitinib (hazard ratio [HR] 1·02, 97·5% CI 0·85-1·23, p=0·8038), 6·1 years (IQR 1·7-not estimable [NE]) for sorafenib (HR 0·97, 97·5% CI 0·80-1·17, p=0·7184), and 6·6 years (IQR 1·5-NE) for placebo. The most common grade 3 or worse adverse events were hypertension (105 [17%] patients on sunitinib and 102 [16%] patients on sorafenib), hand-foot syndrome (94 [15%] patients on sunitinib and 208 [33%] patients on sorafenib), rash (15 [2%] patients on sunitinib and 95 [15%] patients on sorafenib), and fatigue 110 [18%] patients on sunitinib [corrected]. There were five deaths related to treatment or occurring within 30 days of the end of treatment; one patient receiving sorafenib died from infectious colitis while on treatment and four patients receiving sunitinib died, with one death due to each of neurological sequelae, sequelae of gastric perforation, pulmonary embolus, and disease progression. Revised dosing still resulted in high toxicity. INTERPRETATION: Adjuvant treatment with the VEGF receptor tyrosine kinase inhibitors sorafenib or sunitinib showed no survival benefit relative to placebo in a definitive phase 3 study. Furthermore, substantial treatment discontinuation occurred because of excessive toxicity, despite dose reductions. These results provide a strong rationale against the use of these drugs for high-risk kidney cancer in the adjuvant setting and suggest that the biology of cancer recurrence might be independent of angiogenesis. FUNDING: US National Cancer Institute and ECOG-ACRIN Cancer Research Group, Pfizer, and Bayer.

Cardiovascular toxicity after antiangiogenic therapy in persons older than 65 years with advanced renal cell carcinoma.

BACKGROUND: Sorafenib and sunitinib are oral vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs) approved in 2005 and 2006, respectively, for the treatment of patients with renal cell carcinoma (RCC). A population-based, observational cohort study of the cardiovascular risk of VEGFR TKI therapy in elderly RCC patients was conducted. METHODS: Using the Surveillance, Epidemiology, and End Results-Medicare database, this study analyzed patients who were 66 years old or older and were diagnosed with RCC from 2000 to 2009. The incidence of cardiovascular adverse events, including congestive heart failure and cardiomyopathy (CHF/CM), acute myocardial infarction (AMI), stroke, and cardiovascular deaths, was examined through December 2010. A Cox proportional hazards model was created to calculate the hazard ratio (HR), and adjustments were made for age, sex, comorbidity, and the use of other systemic therapy. RESULTS: A total of 171 of 670 patients who received sunitinib or sorafenib had cardiovascular events. The incidence rates for CHF/CM, AMI, and stroke were 0.87, 0.14, and 0.14 per 1000 person-days, respectively. Sunitinib or sorafenib use was associated with an increased risk of cardiovascular events (HR, 1.38; 95% confidence interval [CI], 1.02-1.87) and especially stroke (HR, 2.84; 95% CI, 1.52-5.31) in comparison with 788 patients diagnosed with advanced RCC from 2007 to 2009 who were eligible for Part D but did not receive either agent. In subgroup analyses, patients who were 66 to 74 years old at diagnosis had the highest increased risk of stroke associated with the use of either or both drugs. CONCLUSIONS: Sunitinib and sorafenib might be associated with an increased risk of cardiovascular events and particularly stroke.

BEST: A Randomized Phase II Study of Vascular Endothelial Growth Factor, RAF Kinase, and Mammalian Target of Rapamycin Combination Targeted Therapy With Bevacizumab, Sorafenib, and Temsirolimus in Advanced Renal Cell Carcinoma--A Trial of the ECOG-ACRIN Cancer Research Group (E2804).

PURPOSE: On the basis of evidence that resistance to vascular endothelial growth factor (VEGF) receptor inhibition is caused by hypoxia-driven residual VEGF and other proangiogenic factors, combinations of agents from these classes were hypothesized to improve treatment outcomes relative to single-agent VEGF pathway blockade. PATIENTS AND METHODS: A total of 361 patients with metastatic clear cell renal cell carcinoma were randomly assigned equally to arm A (bevacizumab monotherapy 10 mg/kg intravenously [IV] every 2 weeks), B (bevacizumab 10 mg/kg IV every 2 weeks and temsirolimus 25 mg IV every week), C (bevacizumab 5 mg/kg IV every 2 weeks and sorafenib 200 mg orally twice daily on days 1 to 5, 8 to 12, 15 to 19, and 22 to 26), or D (sorafenib 200 mg twice daily and temsirolimus 25 mg IV weekly). Progression-free survival was the primary end point. RESULTS: Among 331 eligible treated patients, median PFS was 7.5 months for bevacizumab alone (90% CI, 5.8 to 10.8 months), 7.6 months for bevacizumab plus temsirolimus (90% CI, 6.7 to 9.2 months), 9.2 months for bevacizumab plus sorafenib (90% CI, 7.5 to 11.4 months), and 7.4 months for sorafenib plus temsirolimus (90% CI, 5.6 to 7.9 months). Hazard ratios from stratified Cox proportional hazards models were 1.01, 0.89, and 1.07 (with respective P values of .95, .49, and .68) for the three combinations, respectively, compared with bevacizumab alone. Adverse events did not differ significantly among treatment arms. CONCLUSION: The activity of sorafenib, temsirolimus, and bevacizumab administered in doublet combinations did not significantly improve median progression-free survival in comparison with bevacizumab monotherapy.

Effects of Adjuvant Sorafenib and Sunitinib on Cardiac Function in Renal Cell Carcinoma Patients without Overt Metastases: Results from ASSURE, ECOG 2805.

PURPOSE: Sunitinib and sorafenib are used widely in the treatment of renal cell carcinoma (RCC). These agents are associated with a significant incidence of cardiovascular (CV) dysfunction and left ventricular ejection fraction (LVEF) declines, observed largely in the metastatic setting. However, in the adjuvant population, the CV effects of these agents remain unknown. We prospectively defined the incidence of cardiotoxicity among resected, high-risk RCC patients treated with these agents. EXPERIMENTAL DESIGN: Sunitinib, sorafenib, or placebo was administered for up to 12 months in patients with high-risk, resected RCC. LVEF was measured by multigated acquisition (MUGA) scans at standard intervals. Additional CV adverse events were reported according to NCI Common Terminology Criteria for Adverse Events (CTCAE). RESULTS: Among 1,943 patients randomized, 1,599 had at least 1 post-baseline MUGA. Within 6 months, 21 patients (1.3%) experienced a cardiac event, defined as an LVEF decline from baseline that was >15% and below the institutional lower limit of normal. Nine of 513 patients (1.8%) were on sunitinib, 7 of 508 (1.4%) on sorafenib, and 5 of 578 (0.9%) on placebo (P = 0.28 and 0.56 comparing sunitinib and sorafenib to placebo, respectively). With dose interruption or adjustment, 16 of the 21 recovered their LVEF to >50%. The incidence of symptomatic heart failure, arrhythmia, or myocardial ischemia did not differ among groups. CONCLUSIONS: In the adjuvant setting, we prospectively define low incidence of cardiotoxicity with sunitinib and sorafenib. These findings may be related to close CV monitoring, or potentially to fewer CV comorbidities in our nonmetastatic population.

Carbonic anhydrase IX as a potential biomarker of efficacy in metastatic clear-cell renal cell carcinoma patients receiving sorafenib or placebo: analysis from the treatment approaches in renal cancer global evaluation trial (TARGET).

OBJECTIVE: Retrospective data analyses have suggested that carbonic anhydrase IX (CAIX) may have a predictive role in patients with metastatic clear cell renal cell carcinoma (ccRCC) receiving high dose interleukin-2 or sorafenib. We examined the predictive value of CAIX in estimating treatment outcome in patients receiving sorafenib vs. placebo as part of the Treatment Approaches in Renal Cancer Global Evaluation Trial (TARGET) study. MATERIALS AND METHODS: Paraffin embedded tumor tissues were collected from 133 patients from the TARGET study (n = 903). The percentage of CAIX-positive cells was assessed by a single pathologist. The impact of CAIX expression on progression-free survival (PFS, primary endpoint) and tumor shrinkage (TS, secondary endpoint) was analyzed. RESULTS: Clinical characteristics were similarly distributed between patients with low vs. high CAIX staining, as well as patients with available CAIX data vs. not. Median PFS for patients with high CAIX vs. low CAIX expression was 5.5 and 5.4 months, respectively, on the sorafenib arm (P = 0.97), and 1.5 and 1.7 months on the placebo arm (P = 0.76). Median TS for patients with high CAIX status was -14.9% vs. -12.6% in patients with low CAIX status (P = 0.63) on the sorafenib arm, and +1.3% (high CAIX) vs. +4.8% (low CAIX) in patients on the placebo arm (P = 0.60). CONCLUSIONS: Despite suggestive retrospective evidence, data from the TARGET study did not find CAIX expression status to be either predictive of clinical benefit for treatment with sorafenib or of prognostic value in patients with metastatic ccRCC following cytokine therapy.

High dose intermittent sorafenib shows improved efficacy over conventional continuous dose in renal cell carcinoma.

BACKGROUND: Renal cell carcinoma (RCC) responds to agents that inhibit vascular endothelial growth factor (VEGF) pathway. Sorafenib, a multikinase inhibitor of VEGF receptor, is effective at producing tumor responses and delaying median progression free survival in patients with cytokine refractory RCC. However, resistance to therapy develops at a median of 5 months. In an effort to increase efficacy, we studied the effects of increased sorafenib dose and intermittent scheduling in a murine RCC xenograft model. METHODS: Mice bearing xenografts derived from the 786-O RCC cell line were treated with sorafenib according to multiple doses and schedules: 1) Conventional dose (CD) continuous therapy; 2) high dose (HD) intermittent therapy, 3) CD intermittent therapy and 4) HD continuous therapy. Tumor diameter was measured daily. Microvessel density was assessed after 3 days to determine the early effects of therapy, and tumor perfusion was assessed serially by arterial spin labeled (ASL) MRI at day 0, 3, 7 and 10. RESULTS: Tumors that were treated with HD sorafenib exhibited slowed tumor growth as compared to CD using either schedule. HD intermittent therapy was superior to CD continous therapy, even though the total dose of sorafenib was essentially equivalent, and not significantly different than HD continuous therapy. The tumors exposed to HD sorafenib had lower microvessel density than the untreated or the CD groups. ASL MRI showed that tumor perfusion was reduced to a greater extent with the HD sorafenib at day 3 and at all time points thereafter relative to CD therapy. Further the intermittent schedule appeared to maintain RCC sensitivity to sorafenib as determined by changes in tumor perfusion. CONCLUSIONS: A modification of the sorafenib dosing schedule involving higher dose intermittent treatment appeared to improve its efficacy in this xenograft model relative to conventional dosing. MRI perfusion imaging and histologic analysis suggest that this benefit is related to enhanced and protracted antiangiogenic activity. Thus, better understanding of dosing and schedule issues may lead to improved therapeutic effectiveness of VEGF directed therapy in RCC and possibly other tumors.

Comparison of four early posttherapy imaging changes (EPTIC; RECIST 1.0, tumor shrinkage, computed tomography tumor density, Choi criteria) in assessing outcome to vascular endothelial growth factor-targeted therapy in patients with advanced renal cell carcinoma.

BACKGROUND: Vascular endothelial growth factor (VEGF)-targeted therapy has become standard treatment for patients with metastatic renal cell cancer (mRCC). Since these therapies can induce tumor necrosis and minimal tumor shrinkage, Response Evaluation Criteria in Solid Tumors (RECIST) may not be optimal for predicting clinical outcome. OBJECTIVE: To systematically determine the optimal early posttherapy imaging changes (EPTIC) to separate responders and nonresponders at the first posttreatment follow-up computed tomography (CT). DESIGN, SETTING, AND PARTICIPANTS: Seventy mRCC patients with 155 target lesions treated with first-line sunitinib, sorafenib, or bevacizumab at academic medical centers underwent contrast-enhanced thoracic and abdominal CT at baseline and first follow-up after therapy initiation (median: 78 d after therapy initiation; range: 31-223 d). MEASUREMENTS: Evaluations were performed according to (1) RECIST 1.0; (2) Choi criteria; (3) tumor shrinkage (TS) of ≥10% decrease in sum of the longest unidimensional diameter (SLD); and (4) 15% or 20% decrease in mean CT tumor density. Correlation with time to treatment failure (TTF) and overall survival (OS) were compared and stratified by response to each of the radiologic criteria. RESULTS AND LIMITATIONS: Eleven patients were considered responders by RECIST 1.0; 49 based on Choi criteria; 31 patients had ≥10% decrease in the SLD; and 36 and 32 patients had ≥15% and ≥20% decrease, respectively, in mean tumor density on CT. Only the threshold of 10% decrease in the SLD was statistically significant in predicting TTF (10.4 vs 5.1 mo; p=0.02) and OS (32.5 vs 15.8 mo; p=0.002). Receiver operating characteristic analysis yielded a 10% decrease in SLD as the optimal size change threshold for responders. The retrospective nature of the study and measurements by a single oncoradiologist are inherent limitations. CONCLUSIONS: In the retrospectively analyzed study population of mRCC patients receiving VEGF-targeted agents, a 10% reduction in the SLD on the first follow-up CT was an optimal early predictor of outcome.

Carbonic anhydrase IX and pathological features as predictors of outcome in patients with metastatic clear-cell renal cell carcinoma receiving vascular endothelial growth factor-targeted therapy.

OBJECTIVE: To investigate the utility of tumour carbonic anhydrase IX (CAIX) expression and histological features for predicting the outcome in patients with metastatic clear-cell renal cell carcinoma (mRCC) treated with vascular endothelial growth factor (VEGF)-targeted therapy. PATIENTS AND METHODS: We identified 118 patients with mRCC initiating first-line VEGF-targeted therapy, including 94 with clinical and histological data, and available tissue. The primary endpoint was to detect an interaction between sorafenib vs sunitinib treatment and CAIX status on tumour shrinkage. Other treatment outcomes were also assessed. RESULTS: There was heterogeneity in tumour responsiveness to sunitinib or sorafenib according to CAIX status; the mean shrinkage was -17% vs -25% for sunitinib-treated patients with high vs low tumour CAIX expression, compared to -13% vs +9% for sorafenib-treated patients (P interaction, 0.05). A higher tumour clear-cell component was independently associated with greater tumour shrinkage (P= 0.02), response (P= 0.02) and treatment duration (P= 0.02). CONCLUSIONS: Although CAIX expression had no prognostic value in patients with clear-cell mRCC treated with VEGF-targeted therapy, it might be a predictive biomarker for response to sorafenib treatment. Patients with a higher clear-cell component in their tumours are likely to have a superior clinical benefit from VEGF-targeted therapy.

Prognostic factors for overall survival in patients with metastatic renal cell carcinoma treated with vascular endothelial growth factor-targeted agents: results from a large, multicenter study.

PURPOSE: There are no robust data on prognostic factors for overall survival (OS) in patients with metastatic renal cell carcinoma (RCC) treated with vascular endothelial growth factor (VEGF) -targeted therapy. METHODS: Baseline characteristics and outcomes on 645 patients with anti-VEGF therapy-naïve metastatic RCC were collected from three US and four Canadian cancer centers. Cox proportional hazards regression, followed by bootstrap validation, was used to identify independent prognostic factors for OS. RESULTS: The median OS for the whole cohort was 22 months (95% CI, 20.2 to 26.5 months), and the median follow-up was 24.5 months. Overall, 396, 200, and 49 patients were treated with sunitinib, sorafenib, and bevacizumab, respectively. Four of the five adverse prognostic factors according to the Memorial Sloan-Kettering Cancer Center (MSKCC) were independent predictors of short survival: hemoglobin less than the lower limit of normal (P < .0001), corrected calcium greater than the upper limit of normal (ULN; P = .0006), Karnofsky performance status less than 80% (P < .0001), and time from diagnosis to treatment of less than 1 year (P = .01). In addition, neutrophils greater than the ULN (P < .0001) and platelets greater than the ULN (P = .01) were independent adverse prognostic factors. Patients were segregated into three risk categories: the favorable-risk group (no prognostic factors; n = 133), in which median OS (mOS) was not reached and 2-year OS (2y OS) was 75%; the intermediate-risk group (one or two prognostic factors; n = 301), in which mOS was 27 months and 2y OS was 53%; and the poor-risk group (three to six prognostic factors; n = 152), in which mOS was 8.8 months and 2y OS was 7% (log-rank P < .0001). The C-index was 0.73. CONCLUSION: This model validates components of the MSKCC model with the addition of platelet and neutrophil counts and can be incorporated into patient care and into clinical trials that use VEGF-targeted agents.

Does arterial spin-labeling MR imaging-measured tumor perfusion correlate with renal cell cancer response to antiangiogenic therapy in a mouse model?

PURPOSE: To determine whether arterial spin-labeling (ASL) magnetic resonance (MR) imaging findings at baseline and early during antiangiogenic therapy can predict later resistance to therapy. MATERIALS AND METHODS: Protocol was approved by an institutional animal care and use committee. Caki-1, A498, and 786-0 human renal cell carcinoma (RCC) xenografts were implanted in 39 nude mice. Animals received 80 mg sorafenib per kilogram of body weight once daily once tumors measured 12 mm. ASL imaging was performed at baseline and day 14, with additional imaging performed for 786-0 and A498 (3 days to 12 weeks). Mean blood flow values and qualitative differences in spatial distribution of blood flow were analyzed and compared with histopathologic findings for viability and microvascular density. t Tests were used to compare differences in mean tumor blood flow. Bonferroni-adjusted P values less than .05 denoted significant differences. RESULTS: Baseline blood flow was 80.1 mL/100 g/min +/- 23.3 (standard deviation) for A498, 75.1 mL/100 g/min +/- 28.6 for 786-0, and 10.2 mL/100 g/min +/- 9.0 for Caki-1. Treated Caki-1 showed no significant change (14.9 mL/100 g/min +/- 7.6) in flow, whereas flow decreased in all treated A498 on day 14 (47.9 mL/100 g/min +/- 21.1) and in 786-0 on day 3 (20.3 mL/100 g/min +/- 8.7) (P = .003 and .03, respectively). For A498, lowest values were measured at 28-42 days of receiving sorafenib. Regions of increased flow occurred on days 35-49, 17-32 days before documented tumor growth and before significant increases in mean flow (day 77). Although 786-0 showed new, progressive regions with signal intensity detected as early as day 5 that correlated to viable tumor at histopathologic examination, no significant changes in mean flow were noted when day 3 was compared with all subsequent days (P > .99). CONCLUSION: ASL imaging provides clinically relevant information regarding tumor viability in RCC lines that respond to sorafenib.

Retrospective analysis of the safety and efficacy of interleukin-2 after prior VEGF-targeted therapy in patients with advanced renal cell carcinoma.

Agents targeting vascular endothelial growth factor (VEGF) signaling have been advocated as frontline therapy for advanced renal cancer. The role of interleukin 2 (IL-2) therapy after resistance to VEGF-targeted therapy remains unexplored. We conducted a retrospective analysis of the tolerability and efficacy of IL-2 therapy in patients who had previously received VEGF-targeted therapy. Twenty-three consecutive patients who received salvage IL-2 therapy were analyzed. Fifteen patients had received prior tyrosine kinase inhibitors (TKIs) (sorafenib or sunitinib), whereas 8 patients had received bevacizumab alone. Six of 23 patients did not receive week 2 of cycle 1 of treatment. All 6 of these patients had received prior TKIs. The incidence of severe cardiac toxicities, including 1 sudden cardiac death, in patients receiving prior TKI was 40% (95% confidence interval, 16.3-67.7%), significantly higher than what is expected from historical experience. Only 1 of 23 patients proceeded to receive a second cycle of IL-2. No patients achieved a partial or complete response to therapy. This retrospective analysis highlights unexpected and severe cardiac toxicities in patients receiving IL-2 after VEGF-targeted TKI therapy. The assumption that IL-2 therapy can be safely administered after TKI therapy may not be valid. Further examination of the safety of this sequential approach is necessary and more cautious patient selection seems warranted.

Tissue-based research in kidney cancer: current challenges and future directions.

The past several years have seen unprecedented advances in the application of various therapeutic strategies for the treatment of patients with renal cancer. The availability of active immunotherapy, antiangiogenic therapy, and targeted therapy for this disease has brought front and center issues related to choosing the appropriate treatment for particular patient populations. It is increasingly evident that the most promising treatment selection strategies will incorporate identifying specific features of the tumor itself. To facilitate this move toward personalized medicine, it is critically important to establish some standard principles for renal cancer tissue collection, preparation, and analysis for translational research studies. In this article, we identify and discuss some critical issues related to tissue-based kidney cancer research. We focus on five major areas as follows: (a) surgical and image-guided techniques for tissue collection; (b) quality control of specimen collection, processing, storage, and review; (c) issues related to analysis of paraffin embedded tissues; (d) genomic studies; and (e) assessment of reproducibility of assays across institutions. In addition, some practical implementation strategies are proposed. Although many of the topics discussed are specific for renal cancer, several are also relevant to tissue based biomarker investigations in a broad array of malignancies.

Perfusion MDCT enables early detection of therapeutic response to antiangiogenic therapy.

OBJECTIVE: The objective of our study was to determine whether perfusion CT can be used to detect early changes in therapeutic response to antiangiogenic therapy in an animal tumor model. MATERIALS AND METHODS: Twenty-five rats implanted with R3230 mammary adenocarcinoma (diameter, 1.2-2.0 cm) randomly received 7.5 or 30 mg/kg of an antiangiogenic agent, sorafenib, by daily gavage for 4 (n = 4), 9 (n = 9), or 14 (n = 5) days. Seven untreated animals served as a control group. Perfusion MDCT was performed at days 0, 4, 9, and 14 with 0.4 mL of ioversol (350 mg/mL) and included four 5-mm slices covering the entire tumor volume. Changes in tumor growth were determined by volumetric analysis of CT data. Serial changes in tumor volume and blood flow were assessed and correlated with pathology findings. RESULTS: All control tumors grew larger (from 2.0 +/- 0.7 cm(3) at day 0 to 5.9 +/- 1.0 cm(3) at day 14), whereas all treated tumors shrank (from 2.5 +/- 1.1 to 2.1 +/- 1.0 cm(3)), with a statistically significant rate of growth or shrinkage in both groups (p < 0.05). Although perfusion in the control tumors changed little from day 0 to day 14 (day 0, 18.1 +/- 9.2 mL/min/100 g; day 4, 15.8 +/- 5.6; day 9, 21.7 +/- 12.2; day 14, 27.7 +/- 34), in the sorafenib group, the mean blood flow was significantly lower at day 4 (5.2 +/- 3.2 mL/min/100 g, 77% decrease), day 9 (6.4 +/- 4.0 mL/min/100 g, 66% decrease), and day 14 (6.3 +/- 5.2 mL/min/100 g, 83% decrease) compared with day 0 (23.8 +/- 11.6 mL/min/100 g) (p < 0.05). Poor correlation was seen between changes in blood flow and tumor volume for days 0-9 (r(2) = 0.34), 4-9 (r(2) = 0.0004), and 9-14 (r(2) = 0.16). However, when comparing day 4 images with days 9 and 14 images, seven of 14 (50%) sorafenib-treated tumors had focal areas of new perfusion that correlated with areas of histopathologic viability despite the fact that these tumors were shrinking in size from day 4 onward (day 4, 2.18 +/- 0.8 cm(3); day 9, 1.98 +/- 0.8 cm(3)). CONCLUSION: Perfusion MDCT can detect focal blood flow changes even when the tumor is shrinking, possibly indicating early reversal of tumor responsiveness to antiangiogenic therapy. Given that changes in tumor volume after antiangiogenic therapy do not necessarily correlate with true treatment response, physiologic imaging of tumor perfusion may be necessary.