Sunitinib in patients with metastatic renal cell carcinoma

Concepts in advanced renal carcinoma

OBJECTIVES

Treatment options for advanced renal cell carcinoma have increased dramatically over the past 6 years as a result of improved understanding of the biology of renal cancer and the development of therapies to target pathways relevant to tumor progression.

DATA SOURCES

Research-based articles.

CONCLUSION

New therapies to treat advanced renal cell cancer results in a need for evidence-based decision making when discussing treatment choices.

IMPLICATIONS FOR NURSING PRACTICE

Knowledge of therapeutic strategies, their proposed mechanism of action, potential adverse events, and management strategies provides nurses with a foundation to provide appropriate patient education and effective management of treatment-related side effects, assisting patients to maximize clinical outcomes.

Sunitinib adverse events in metastatic renal cell carcinoma: a meta-analysis

BACKGROUND

Sunitinib, a multi-targeted receptor tyrosine kinase inhibitor, has demonstrated survival benefit in patients with metastatic renal cell carcinoma (mRCC); however, significant adverse events (AEs) have been associated with its use. The significant variation in the reported incidences of AEs has prompted this meta-analysis to quantify the risk and explore associated predictors.

METHODS

According to predefined selection criteria, a literature search identified 12 studies that were included in the analyses.

RESULTS

The meta-analysis included 5,658 patients; 66 % patients had prior systemic therapy whereas the remaining patients (34 %) received sunitinib in the first-line setting. For any grade toxicity, skin rash, fatigue, diarrhea, and mucositis were the most frequently encountered events (81, 52, 45, and 33 %, respectively). Anemia, neutropenia, or thrombocytopenia of any grade occurred in more than one-third of patients, although grades 3 or 4 were less common. Any grade raised by liver enzymes or serum creatinine occurred in 40 and 44 % of patients, respectively. Meta-regression analyses showed that study size was inversely related to the risk of experiencing fatigue, diarrhea, mucositis, anemia, and thrombocytopenia. In particular, the incidence of AEs was higher when sunitinib was used in pretreated versus naive patients; however, there was no significant difference between the two groups concerning the incidence of laboratory abnormalities. We addressed the limitations of reporting AEs in clinical studies.

CONCLUSIONS

The present meta-analysis quantified sunitinib-associated AEs. The derived estimates would be similar to that to be expected from the use of sunitinib in community practice in unselected patients with metastatic renal cell carcinoma (mRCC).

Identification and functional characterization of pVHL-dependent cell surface proteins in renal cell carcinoma

The identification of cell surface accessible biomarkers enabling diagnosis, disease monitoring, and treatment of renal cell carcinoma (RCC) is as challenging as the biology and progression of RCC is unpredictable. A hallmark of most RCC is the loss-of-function of the von Hippel-Lindau (pVHL) protein by mutation of its gene (VHL). Using the cell surface capturing (CSC) technology, we screened and identified cell surface N-glycoproteins in pVHL-negative and positive 786-O cells. One hundred six cell surface N-glycoproteins were identified. Stable isotope labeling with amino acids in cell culture-based quantification of the CSC screen revealed 23 N-glycoproteins whose abundance seemed to change in a pVHL-dependent manner. Targeted validation experiments using transcriptional profiling of primary RCC samples revealed that nine glycoproteins, including CD10 and AXL, could be directly linked to pVHL-mediated transcriptional regulation. Subsequent human tumor tissue analysis of these cell surface candidate markers showed a correlation between epithelial AXL expression and aggressive tumor phenotype, indicating that pVHL-dependent regulation of glycoproteins may influence the biologic behavior of RCC. Functional characterization of the metalloprotease CD10 in cell invasion assays demonstrated a diminished penetrating behavior of pVHL-negative 786-O cells on treatment with the CD10-specific inhibitor thiorphan. Our proteomic surfaceome screening approach in combination with transcriptional profiling and functional validation suggests pVHL-dependent cell surface glycoproteins as potential diagnostic markers for therapeutic targeting and RCC patient monitoring.

Bevacizumab in combination with IFN-α in metastatic renal cell carcinoma: the AVOREN trial

Metastatic renal cell carcinoma (mRCC) is tumor resistant to all cytotoxic agents. During the last decade, effective targeted therapies emerged including sunitinib, pazopanib and the combination of bevacizumab with IFN-α. The use of bevacizumab plus IFN-α combination in mRCC is supported by the AVOREN trial. Although the primary end point of the AVOREN trial was overall survival, progression-free survival was used to evaluate efficacy and served as the basis of regulatory submission owing to the advent of targeted agents that probably resulted in the prolongation of overall survival in both experimental and control arms. The doubling of median progression-free survival in the AVOREN trials (from 5.4 to 10.2 months) is remarkably similar compared with the results of Phase III trials with sunitinib and pazopanib. Bevacizumab plus IFN-α is the only combined regimen currently used in mRCC and serves as a comparator in the trials combining bevacizumab with other agents.

Activation of alternate prosurvival pathways accounts for acquired sunitinib resistance in U87MG glioma xenografts

Acquired drug resistance represents a major obstacle to using sunitinib for the treatment of solid tumors. Here, we examined the cellular and molecular alterations in tumors that are associated with acquired brain tumor resistance to sunitinib by using an in vivo model. U87MG tumors obtained from nude mice that received sunitinib (40 mg/kg/day) for 30 days were classified into sunitinib-sensitive and -resistant groups based on tumor volume and underwent targeted gene microarray and protein array analyses. The expression of several angiogenesis-associated genes was significantly modulated in sunitinib-treated tumors compared with those in control tumors (p<0.05), whereas no significant differences were observed between sunitinib-sensitive and -resistant tumors (p>0.05). Tumor vasculature based on microvessel density, neurogenin 2 chondroitin sulfate proteoglycan density, and α-smooth muscle actin density was also similar in sunitinib-treatment groups (p>0.05). The moderate increase in unbound sunitinib tumor-to-plasma area-under-the-curve ratio in sunitinib-resistant mice was accompanied by up-regulated ATP-binding cassette G2 expression in tumor. The most profound difference between the sunitinib-sensitive and -resistant groups was found in the expression of several phosphorylated proteins involved in intracellular signaling. In particular, phospholipase C-γ1 phosphorylation in sunitinib-resistant tumors was up-regulated by 2.6-fold compared with that in sunitinib-sensitive tumors (p<0.05). In conclusion, acquired sunitinib resistance in U87MG tumors is not associated with revascularization in tumors, but rather with the activation of alternate prosurvival pathways involved in an escape mechanism facilitating tumor growth and possibly insufficient drug uptake in tumor cells caused by an up-regulated membrane efflux transporter.

Biweekly sunitinib regimen reduces toxicity and retains efficacy in metastatic renal cell carcinoma: a single-center experience with 31 patients

OBJECTIVES

Sunitinib is the standard care for first-line treatment of metastatic renal cell carcinoma. The aim of this study was to determine whether a sunitinib regimen of 50 mg/day 2-weeks on/1-week off could maintain the same dose-intensity as the standard 4-weeks on/2-weeks off schedule, and provide the same efficacy in terms of objective response, progression-free survival and overall survival, while reducing drug-related toxicity.

METHODS

A total of 31 patients with metastatic renal cell carcinoma received sunitinib orally at the dose of 50 mg/day in a 2-weeks on/1-week off regimen until disease progression or intolerable toxicities occurred.

RESULTS

All enrolled patients were assessable in terms of toxicity and response. They received treatment for a median of 16 months (range 2.0-36.0+ months). A total of 13 patients (42%) obtained an objective response; disease stabilization was achieved in 10 patients (32%), whereas eight patients (26%) experienced disease progression. The most important toxicities were anemia, gastrointestinal effects, fatigue and hypertension, but they were all controlled.

CONCLUSIONS

Sunitinib 50 mg given orally in a 2-weeks on/1-week off regimen can provide a high response rate and avoid drug-related toxicities, achieving the same dose intensity as the standard schedule, and probably longer disease control.

Extraskeletal myxoid chondrosarcoma: tumor response to sunitinib

Background

Extraskeletal myxoid chondrosarcoma (EMCS) is a rare soft tissue sarcoma of uncertain differentiation, characterized in most cases by a translocation that results in the fusion protein EWSR1-CHN (the latter even called NR4A3 or TEC). EMCS is marked by >40% incidence of metastases in spite of its indolent behaviour. It is generally resistant to conventional chemotherapy, and, to the best of our knowledge, no data have been reported to date about the activity of tirosin-kinase inhibitor (TKI) in this tumor. We report on two consecutive patients carrying an advanced EMCS treated with sunitinib.

Methods

Since July 2011, 2 patients with progressive pretreated metastatic EMCS (Patient1: woman, 58 years, PS1; Patient2: man, 63 years, PS1) have been treated with continuous SM 37.5 mg/day, on an individual use basis. Both patients are evaluable for response. In both cases diagnosis was confirmed by the presence of the typical EWSR1-CHN translocation.

Results

Both patients are still on treatment (11 and 8 months). Patient 1 got a RECIST response after 4 months from starting sunitinib, together with a complete response by PET. An interval progression was observed after stopping sunitinib for toxicity (abscess around previous femoral fixation), but response was restored after restarting sunitinib. Patient 2 had an initial tumor disease stabilization detected by CT scan at 3 months. Sunitinib was increased to 50 mg/day, with evidence of a dimensional response 3 months later.

Conclusions

Sunitinib showed antitumor activity in 2 patients with advanced EMCS. Further studies are needed to confirm these preliminary results.

Activity of single-agent bevacizumab in patients with metastatic renal cell carcinoma previously treated with vascular endothelial growth factor tyrosine kinase inhibitors

PURPOSE

The activity of systemic agents after progression when using vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibition (TKI) and mammalian target of rapamycin (mTOR) inhibition in patients with metastatic renal cell carcinoma (mRCC) is poorly characterized. The anti-vascular endothelial growth factor (VEGF) monoclonal antibody bevacizumab has a broad US Food and Drug Administration label and National Comprehensive Cancer Network guideline level 2b recommendation in this setting; we thus explored our institutional experience in this population.

METHODS

We conducted a retrospective analysis of patients with mRCC who were treated with bevacizumab in the second- and/or third-line settings; the primary endpoint was progression-free survival (PFS). Overall response rates (ORR), overall survival (OS), and toxicity were analyzed.

RESULTS

Twenty-one patients were treated with bevacizumab: the median age was 63 years old; 80% were white and 14% were black; 80% had clear cell histology. All the patients had prior VEGFR TKI therapy; 43% had prior mTOR inhibitor; the median number of prior therapies was 3. The median PFS was 4.4 months (95% CI, 2.8-9.6 months), and the median OS was 19.4 months (95% CI, 9.9-NR months). ORR was 9.5%; 52% of subjects had stable disease as best response, and 52% had disease progression. For subjects treated with prior VEGF and mTOR inhibitors, median PFS and OS were 4.4 and 13.2 months, respectively. Grade 3 to 4 toxicities included fatigue (29%), dehydration (24%), failure to thrive (10%), constipation (10%), and muscle weakness (10%).

CONCLUSIONS

Single-agent bevacizumab has acceptable toxicity and moderate disease-stabilizing activity in selected patients with mRCC who have failed prior VEGFR TKI and mTOR inhibitors. These data support clinical benefit to continued ongoing VEGF inhibition. Further prospective studies of bevacizumab alone or with alternative targeted agents in previously treated populations with mRCC are warranted.

Experience with sunitinib in the treatment of metastatic renal cell carcinoma

Following approval of the oral, multitargeted tyrosine kinase inhibitor sunitinib malate for the treatment of patients with metastatic renal cell carcinoma (mRCC) in Europe and the USA in 2006, the agent has had a substantial impact on the treatment landscape in this setting. Sunitinib is now recommended in international treatment guidelines for the first-line treatment of favourable- or intermediate-risk mRCC and as an alternative option in poor-risk mRCC. In the 6 years since the approval of sunitinib, the range of agents available for the treatment of mRCC has expanded substantially, and this, together with a number of additional therapies in late-stage development, has increased the treatment options available to patients. Results from a phase III trial and a global expanded access study have provided robust data to support the efficacy of sunitinib in mRCC, including in real-world populations. Data also suggest a significant quality of life benefit with sunitinib, with superior patient-reported outcomes observed with this agent compared with interferon-α therapy. Both clinical and real-world study data also support the safety profile of sunitinib; most treatment-associated adverse events are mild to moderate in severity and can be managed effectively with close monitoring and proactive management. Clinical experience with sunitinib has demonstrated that therapy management, involving optimal dosing, maximum treatment duration and prompt and effective adverse event management, supports optimal patient outcomes with sunitinib. In this review we discuss clinical experience with sunitinib in mRCC, with an emphasis on real-world data, and utilize clinical case studies to examine the successful implementation of therapy management strategies for optimal patient outcomes. An increasing body of evidence suggests that side effects associated with sunitinib therapy, including hypertension, hand-foot syndrome and hypothyroidism, may represent effective markers of treatment response, and these will also be discussed.

Neoadjuvant targeted therapy in a primary metastasized renal cell cancer patient leads to down-staging of inferior vena cava thrombus (IVC) enabling a cardiopulmonary bypass-free tumor nephrectomy: a case report

BACKGROUND

We report on a 62-year-old gentleman presenting at our urological department with an advanced renal cell cancer of the right kidney (10 cm in diameter), with an extensive caval vein thrombus (level IV) and bilateral pulmonary metastases. Another suspicious lesion at the left hemithorax was radiologically described.

METHOD

A presurgical, neoadjuvant systemic therapy with sunitinib, a tyrosine kinase inhibitor, was initiated for 4 cycles in total (50 mg/day; 4 weeks on/2 weeks off). The cytoreductive nephrectomy was performed following the fourth cycle of sunitinib and after a 14-day break. Transesophageal echocardiography was used for intraoperative monitoring of the caval vein thrombus. Systemic treatment with sunitinib was continued 4 weeks after surgery.

RESULTS

A significant reduction in tumor size, metastatic sites and down-staging of IVC from level IV to level III according to Novick classification was achieved.

CONCLUSION

Significant down-staging of the tumor caval vein thrombus which initially reached the right atrium enabled us to perform surgery limited to the abdominal cavity without extracorporeal circulation nor hypothermia.

Hypertension management in patients with renal cell cancer treated with anti-angiogenic agents

Inhibitors of the vascular endothelial growth factor (vegf-is) signalling pathway have fundamentally changed the treatment of metastatic renal cell carcinoma (mrcc). Hypertension is one of the most common side effects of vegf-is and has been reported with almost every vegf-i used for treatment to date. The exact mechanism of vegf-i-induced hypertension appears complex and multifactorial, and it remains to be fully explained. No randomized clinical trials are available to guide the management of hypertension during vegf-i treatment in mrcc patients. The guiding principles suggested here summarize the consensus of opinions on the diagnosis and management of vegf-i-induced hypertension during treatment of mrcc obtained from an expert working group composed of 4 Canadian medical oncologists and 5 Canadian hypertension specialists. The Canadian Hypertension Education Program guidelines, available literature, and expert opinion were used to develop the guiding principles.

Simultaneous targeting of TNF and Ang2 with a novel bispecific antibody enhances efficacy in an in vivo model of arthritis

Despite the clinical success of anti-tumor necrosis factor (TNF) therapies in the treatment of inflammatory conditions such as rheumatoid arthritis, Crohn disease and psoriasis, full control of the diseases only occurs in a subset of patients and there is a need for new therapeutics with improved efficacy against broader patient populations. One possible approach is to combine biological therapeutics, but both the cost of the therapeutics and the potential for additional toxicities needs to be considered. In addition to the various mediators of immune and inflammatory pathways, angiogenesis is reported to contribute substantially to the overall pathogenesis of inflammatory diseases. The combination of an anti-angiogenic agent with anti-TNF into one molecule could be more efficacious without the risk of severe immunosuppression. To evaluate this approach with our Zybody technology, we generated bispecific antibodies that contain an Ang2 targeting peptide genetically fused to the anti-TNF antibody adalimumab (Humira®). The bispecific molecules retain the binding and functional characteristics of the anti-TNF antibody, but with additional activity that neutralizes Ang2. In a TNF transgenic mouse model of arthritis, the bispecific anti-TNF-Ang2 molecules showed a dose-dependent reduction in both clinical symptoms and histological scores that were significantly better than that achieved by adalimumab alone.

Phase 1b dose-finding study of motesanib with docetaxel or paclitaxel in patients with metastatic breast cancer

The purpose of this study was to investigate the safety, tolerability, and pharmacokinetics of motesanib when combined with docetaxel or paclitaxel in patients with metastatic breast cancer. In this open-label, dose-finding, phase 1b study, patients received motesanib 50 or 125-mg orally once daily (QD), beginning day 3 of cycle 1 of chemotherapy, continuously in combination with either paclitaxel 90 mg/m² on days 1, 8, and 15 every 28-day cycle (Arm A) or docetaxel 100 mg/m² on day 1 every 21-day cycle (Arm B). Dose escalation to motesanib 125 mg QD occurred if the incidence of dose-limiting toxicities (DLTs, primary endpoint) was ≤33 %. If the maximum tolerated dose (MTD) of motesanib was established in Arm B, additional patients could receive motesanib at the MTD plus docetaxel 75 mg/m². Forty-six patients were enrolled and 45 received ≥1 dose of motesanib. The incidence of DLTs was <33 % in all cohorts; thus, motesanib 125 mg QD was established as the MTD. Seven patients (16 %) had grade 3 motesanib-related adverse events including cholecystitis (2 patients) and hypertension (2 patients). Pharmacokinetic parameters of motesanib were similar to those reported in previous studies. The objective response rate was 56 % among patients with measurable disease at baseline who received motesanib in combination with taxane-based chemotherapy. The addition of motesanib to either paclitaxel or docetaxel was generally tolerable up to the 125-mg QD dose of motesanib. The objective response rate of 56 % suggests a potential benefit of motesanib in combination with taxane-based chemotherapy.

The potential beneficial effects of drugs on the immune response to vaccination

Many immunotherapeutic agents in phase II cancer studies have given optimistic results, which were not confirmed in larger randomized studies. Here we explore the evidence that, contrary to previous opinion, many chemotherapeutic agents and other classes of drugs may enhance the response to therapeutic vaccines by reducing inflammation and/or by inhibiting regulatory T lymphocytes or myeloid-derived suppressor cells. In addition, some of these agents, such as the immunomodulatory drugs, may produce marked costimulatory activities as in the case of lenalidomide, which also has marked anti-inflammatory properties. With the first approval for a vaccine-based therapy for prostate cancer, we propose that many more vaccines will be able to achieve approval, especially when combined with the optimal chemotherapy and/or immunomodulatory drug schedule.

[Cardiotoxicity of chemotherapies]

The spectrum of chemotherapy's cardiac side effect of chemotherapy has expanded with the new combinations of cytotoxic and targeted therapies over the past 10 years. Moreover, cancer therapy administrated to "new" populations, especially elderly patients or patients with cardiovascular disease and/or coronary artery disease history, has increased considerably. According to the American College of Cardiology and American Heart Association (ACC/AHA), patients receiving chemotherapy can be considered in the A group of heart failure. Many cardiovascular adverse effects appear with cancer therapy and suspend treatment purchase, or leading to an alteration of quality of life, and increasing mortality risks. The most clinically evident cardiotoxicity and best known is the anthracyclines adverse effect. Other cytotoxic are associated with a significant risk of cardiovascular complications include alkylating agents such as 5-fluorouracil and paclitaxel. Cardiovascular adverse effects are associated with the use of targeted therapies such as tyrosine kinase inhibitors: trastuzumab, bevacizumab. At the same time, drugs used to hematological malignancies, as acid all-trans-retinoic acid and arsenic trioxide are cardiotoxics. The most serious cardiac complications of cancer therapies is heart congestive failure, mainly due to the use of anthracyclines, cyclophosphamide and trastuzumab, usually at high doses. Myocardial ischemia is mainly caused by interferon and antimetabolites. Other side effects may occur such as hypotension, hypertension, arrhythmias and conduction disturbances, pericarditis, and thromboembolic complications.

Cardiovascular and systemic microvascular effects of anti-vascular endothelial growth factor therapy for cancer

OBJECTIVES

This study sought to evaluate the contribution of microvascular functional rarefaction and changes in vascular mechanical properties to the development of hypertension and secondary ventricular remodeling that occurs with anti-vascular endothelial growth factor (VEGF) therapy.

BACKGROUND

Hypertension is a common side effect of VEGF inhibitors used in cancer medicine.

METHODS

Mice were treated for 5 weeks with an anti-murine VEGF-A monoclonal antibody, antibody plus ramipril, or sham treatment. Microvascular blood flow (MBF) and blood volume (MBV) were quantified by contrast-enhanced ultrasound in skeletal muscle, left ventricle (LV), and kidney. Echocardiography and invasive hemodynamics were used to assess ventricular function, dimensions and vascular mechanical properties.

RESULTS

Ambulatory blood pressure increased gradually over the first 3 weeks of anti-VEGF therapy. Compared with controls, anti-VEGF-treated mice had similar aortic elastic modulus and histological appearance, but a marked increase in arterial elastance, indicating increased afterload, and elevated plasma angiotensin II. Increased afterload in treated mice led to concentric LV remodeling and reduced stroke volume without impaired LV contractility determined by LV peak change in pressure over time (dp/dt) and the end-systolic dimension-pressure relation. Anti-VEGF therapy did not alter MBF or MBV in skeletal muscle, myocardium, or kidney; but did produce cortical mesangial glomerulosclerosis. Ramipril therapy almost entirely prevented the adverse hemodynamic effects, increased afterload, and LV remodeling in anti-VEGF-treated mice.

CONCLUSIONS

Neither reduced functional microvascular density nor major alterations in arterial mechanical properties are primary causes of hypertension during anti-VEGF therapy. Inhibition of VEGF leads to an afterload mismatch state, increased angiotensin II, and LV remodeling, which are all ameliorated by angiotensin-converting enzyme inhibition.

Postrecurrent oncologic outcome of patients with ovarian clear cell carcinoma

OBJECTIVES

To estimate the long-term clinical outcome of patients with recurrent clear cell carcinoma (RCCC) of the ovary in comparison with those with recurrent serous adenocarcinoma (RSAC).

PATIENTS AND METHODS

In this study, 113 patients with RCCC and 365 patients with RSAC were analyzed. The pathological slides were evaluated under central pathological review. End points were the overall survival (OS), postrecurrence survival (PRS), and timing of death of mortality cases.

RESULTS

The 5-year OS and PRS rates of patients with RCCC were 22.5 and 13.2%, respectively. In both OS and PRS, the prognosis of patients with RCCC was significantly poorer than that of the patients with RSAC (OS: P = 0.0007; PRS: P < 0.0001). Moreover, regardless of the status of the residual tumor (RT) at the initial surgery, the OS and PRS of the patients with RCCC were markedly shorter than those with RSAC (RT [-]: OS, P = 0.0005: PRS, P = 0.0002: RT [+]: OS, P < 0.0001: PRS, P < 0.0001). In multivariable analysis, the histological type was a significantly poorer prognostic indicator for OS and PRS (OS [RCCC vs RSAC]: hazard ratio, 2.302: 95% confidence interval, 1.723-3.076; P < 0.0001: PRS [RCCC vs RSAC]; hazard ratio, 2.353: 95% confidence interval, 1.756-3.155; P < 0.0001). Even in the deceased patients (n = 350), the rate of patients with RCCC dying within 12 months of recurrence was higher than that of RSAC (RCCC, 67.8%; RSAC, 40.7%; [P < 0.0001]).

CONCLUSIONS

The long-term clinical outcome of patients with RCCC was extremely poor. We confirmed that RCCC should be investigated as a different malignancy compared with RSAC.

Sorafenib or sunitinib as postoperative adjuvant therapy for Chinese patients with locally advanced clear cell renal cell carcinoma at high risk for disease recurrence

OBJECTIVE

To evaluate the efficacy and safety of targeted agents (sorafenib and sunitinib) as postoperative adjuvant therapy in Chinese patients with clear cell renal cell carcinoma (CC-RCC) who are at high risk for disease recurrence.

MATERIALS AND METHODS

Forty-three patients treated at our center between December 2007 and December 2010 with locally advanced CC-RCC who were at a high risk for disease recurrence were enrolled into the study. The criteria for high risk of CC-RCC recurrence postoperatively were defined according to the Mayo Clinic stage, size, grade, and necrosis (SSIGN) score for CC-RCC. After radical nephrectomy, patients received either sorafenib (group A, n = 20) or sunitinib (group B, n = 23) and were followed up for at least 1 year to determine the efficacy and safety of the test products. The duration of maintenance targeted medication treatment was approximately 1 year. Group C consisted of 388 CC-RCC patients treated at our center between 1992 and 2007, who were at high risk for disease recurrence and who received no adjuvant therapy.

RESULTS

The demography characteristics were similar among the 3 groups. The overall rate of recurrence in groups A and B was not different (15.0% and 17.4% (P > 0.05), respectively), which was lower than that of group C (38.7%, P < 0.05 compared with groups A and B). Disease-free survival (DFS) was longer in groups A and B (18.9 ± 5.9 months and 16.9 ± 6.1 months [P > 0.05], respectively), compared with group C (13.3 ± 7.2 months, P < 0.05 compared with groups A and B). The common adverse effects of targeted therapy included hand-foot syndrome, fatigue, diarrhea, taste disturbance, rash, hypertension, alopecia, stomatitis, neutropenia, nausea, pruritus, hypothyroidism in groups A and B. The adverse effects were mild in both groups and the incidence was not significantly different between groups A and B.

CONCLUSIONS

Targeted adjuvant therapy postoperatively with sorafenib or sunitinib in patients with CC-RCC who are at a high risk for disease recurrence was well tolerated and effective in reducing the rate of CC-RCC recurrence in these patients. This study is an attempt to assess the utility of adjuvant tyrosine kinase inhibitors (TKIs) after surgery for renal carcinoma. The apparently improved outcomes, compared with a historical control population, are of sufficient interest to support the continuation of an ongoing randomized clinical trial to validate the hypothesis.

Therapy management with sunitinib in patients with metastatic renal cell carcinoma: key concepts and the impact of clinical biomarkers

Targeted agents have improved prognosis for patients with metastatic renal cell carcinoma (mRCC), and they are changing therapeutic expectations with respect to long-term clinical outcomes for these patients. However, in order to obtain the maximum clinical benefit from targeted agents, effective therapy management is essential and includes optimization of dosing and treatment duration, as well as adequate side-effect management. Sunitinib has demonstrated efficacy for the treatment of patients with mRCC and is a reference standard of care for first-line therapy. However, in clinical practice, it is difficult to determine the best treatment strategy with targeted agents due to long-term tolerability and the development of resistance. An individualized therapeutic strategy in RCC requires a comprehensive understanding of the biology of response and resistance to targeted therapy. Here we review the clinical data regarding the efficacy and safety for sunitinib and highlight the importance of therapy management, as well as the potential use of clinical biomarkers in order to maximize the clinical benefit from sunitinib treatment in patients with mRCC.

Antitumor Activity and Safety of Tivozanib (AV-951) in a Phase II Randomized Discontinuation Trial in Patients With Renal Cell Carcinoma

Purpose

The antitumor activity and safety of tivozanib, which is a potent and selective vascular endothelial growth factor receptor-1, -2, and -3 inhibitor, was assessed in patients with advanced/metastatic renal cell carcinoma (RCC).

Patients and Methods

In this phase II, randomized discontinuation trial, 272 patients received open-label tivozanib 1.5 mg/d (one cycle equaled three treatment weeks followed by a 1-week break) orally for 16 weeks. Thereafter, 78 patients who demonstrated ≥ 25% tumor shrinkage continued to take tivozanib, and 118 patients with less than 25% tumor change were randomly assigned to receive tivozanib or a placebo in a double-blind manner; patients with ≥ 25% tumor growth were discontinued. Primary end points included safety, the objective response rate (ORR) at 16 weeks, and the percentage of randomly assigned patients who remained progression free after 12 weeks of double-blind treatment; secondary end points included progression-free survival (PFS).

Results

Of 272 patients enrolled onto the study, 83% of patients had clear-cell histology, 73% of patients had undergone nephrectomy, and 54% of patients were treatment naive. The ORR after 16 weeks of tivozanib treatment was 18% (95% CI, 14% to 23%). Of the 118 randomized patients, significantly more patients who were randomly assigned to receive double-blind tivozanib remained progression free after 12 weeks versus patients who received the placebo (49% v 21%; P = .001). Throughout the study, the ORR was 24% (95% CI, 19% to 30%), and the median PFS was 11.7 months (95% CI, 8.3 to 14.3 months) in the overall study population. The most common grade 3 and 4 treatment-related adverse event was hypertension (12%).

Conclusion

Tivozanib was active and well tolerated in patients with advanced RCC. These data support additional development of tivozanib in advanced RCC.

Importance of continuing therapy and maintaining one-month relative dose intensity in sunitinib therapy for metastatic renal cell carcinoma

Sunitinib is a multikinase inhibitor used as first- and second-line treatment of metastatic renal cell carcinoma. However, there are few reports on the necessary doses of sunitinib to get better clinical outcome in general practice with Japanese patients. We examined the relationship between the efficacy and the necessary doses of sunitinib therapy in a multi-institutional retrospective study. A study population of 94 metastatic renal cell carcinoma patients was eligible for this investigation. The most frequent grade 3/4 laboratory adverse events were decreased platelet (31.9 %) and white blood cell (21.3 %) counts. Treatment was discontinued in 18 patients (31.0 %) initially receiving a 50-mg/day dose within only one course, and median 1-month relative dose intensity was 74.3 %. Median progression-free survival time was 2.3 months in patients treated for only one course and 10.8 months in patients treated for more than one course (P < 0.001). Multivariate analysis showed that only one course of treatment and 60 % and less of 1-month relative dose intensity were significantly associated with inferior progression-free survival (P < 0.001 and P = 0.027, respectively). Moreover, modified Memorial Sloan-Kettering Cancer Center poor risk was significantly associated with progression-free survival time. It is difficult for Japanese patients to continue an initial dose of sunitinib therapy without drug withdrawal. Continuing therapy for more than one course and maintaining more than 60 % of 1-month relative dose intensity were very important in the prolongation of progression-free survival time regardless of the initial treatment doses.

Serum creatine kinase increase in patients treated with tyrosine kinase inhibitors for solid tumors

Regarding the frequency of muscular complains with the use of tyrosine kinase inhibitors (TKIs), we hypothesize that creatine kinase (CK) elevation may be more frequent than usually reported. We conducted a prospective study on patients treated with TKIs for solid tumors, to assess the incidence of CK increase on treatment. Most of the patients (105/155) had a gastrointestinal stromal tumor. Treatments were carried out with the following drugs: imatinib (87 cases); sunitinib (21 cases); HER antagonists (14 cases), other TKIs (15 cases); and imatinib-based combinations (2 cases). Myalgias were found in 50/155 patients (32%). Fifty-four patients (35%; 95%CI, 27-42%) had elevated CK. According to NCI-CTC grading, there was 49/54 (31%) grade 1 and 5/54 (3%) grade 2 (2.5 to 5 times ULN). CK elevation was more frequent with imatinib than with other TKIs (39 cases, 45% vs. 14 cases, 21%, respectively; chi-squared test: P=0.003), and CK was more likely to be abnormal in patients treated with any TKI for more than 6 months. We found increased CK in about one-third of patients under TKIs for solid tumors, including 3% of patients with CK as high as 2.5-5 times ULN.

Duration of targeted therapy for metastatic renal cell carcinoma: a review of current practices

The development of targeted agents has substantially improved clinical outcomes for patients with metastatic renal cell carcinoma. The optimum duration of treatment with these agents is not yet clear, particularly as targeted agents may often result in disease stabilization as well as in tumour response. Some clinicians may choose to switch to an alternative agent in the absence of tumour response or in the event of the occurrence of side effects, which can result in patients moving rapidly through the available treatment options. This review evaluates the duration of treatment observed with targeted agents that are approved for first-line treatment of metastatic renal cell carcinoma and considers the reasons for switching or discontinuing therapy. In addition, practical strategies for achieving optimal treatment duration, through adverse event management, are discussed.

Sunitinib: the first to arrive at first-line metastatic renal cell carcinoma

Tyrosine kinase inhibitors (TKIs) are beneficial for the treatment of renal cell carcinoma (RCC), gastrointestinal stromal tumors (GIST), pancreatic neuroendocrine tumors (pNETs), and other tumors. The antitumor activity of sunitinib has been based on time-related parameters such as progression-free survival (PFS) and overall survival (OS). Advances in knowledge of the molecular mechanisms and oncogenic processes associated with RCC have enabled the availability of rational targets for pharmacotherapy. Although each small molecule is modeled to block the activity of selected kinase signaling enzymes, it is increasingly evident that many have nontargeted effects (on other kinases) that may cause unexpected complications. The recommended dose for sunitinib in patients with advanced RCC is a 50 mg oral daily dose, with or without food, on a 4/2 week schedule (4 weeks "on" vs. 2 weeks "off") until progression. An alternative continuous 37.5 mg/day dosing schedule has also been evaluated and appears to be well tolerated, allowing the maintenance of the dose density of sunitinib with a similar outcome. The continuous administration schedule provides a constant exposure to the drug, and may prevent potential tumor regrowth and angiogenesis recovery. Most side effects are reversible and should not result in sunitinib discontinuation. In this article, the body of evidence behind the use of sunitinib in metastatic RCC (mRCC) compared to other targeted agents that have recently come into the field is summarized, and the need for correct management of an adverse event profile in order to better optimize available treatment options is underlined.

Toll-like receptor 7 agonist therapy with imidazoquinoline enhances cancer cell death and increases lymphocytic infiltration and proinflammatory cytokine production in established tumors of a renal cell carcinoma mouse model

Imidazoquinolines are synthetic toll-like receptor 7 and 8 agonists and potent dendritic cell activators with established anticancer activity. Here we test the hypothesis that imidazoquinoline has in vivo efficacy within established renal cell carcinoma (RCC) tumors. Immunocompetent mice bearing syngeneic RCC xenografts were treated with imidazoquinoline or placebo at two separate time points. Harvested tumors were assayed by TUNEL/caspase-3/Ki67 immunostains to evaluate cell death/apoptosis/proliferation, and CD3/B220/CD45 immunostains to evaluate T-cell lymphocyte/B-cell lymphocyte/pan-leukocyte tumor infiltration. ELISA measurement of tumor and serum levels of proinflammatory cytokines, IL-6 and MCP-1, was performed. A single imidazoquinoline dose significantly decreased RCC tumor growth by 50% and repeat dosing compounded the effect, without observed weight loss or other toxicity. Tumor immunostaining revealed significant increases in cell death and apoptosis without changes in cell proliferation, supporting induction of apoptosis as the primary mechanism of tumor growth suppression. Imidazoquinoline treatment also significantly enhanced peritumoral aggregation and intratumoral infiltration by T-cell lymphocytes, while increasing intratumoral (but not serum) levels of proinflammatory cytokines. In conclusion, imidazoquinoline treatment enhances T-cell lymphocyte infiltration and proinflammatory cytokine production within established mouse RCC tumors, while suppressing tumor growth via induction of cancer cell apoptosis. These findings support a therapeutic role for imidazoquinoline in RCC.

Drug-induced heart failure

PURPOSE

The published evidence on the role of various drugs and medication classes in causing or exacerbating heart failure (HF) is reviewed, with discussion of precautions and management strategies for use in clinical practice.

SUMMARY

A literature search was conducted to identify reports of new-onset HF and exacerbations of HF associated with medication use published from 1960 to January 2011. A large body of evidence from controlled clinical trials has led to an improved understanding of well-established causes of drug-induced HF symptoms (e.g., thiazolidinediones, certain older chemotherapy agents) while implicating a wide range of other commonly used drugs and drug classes (e.g., tyrosine kinase inhibitors, biological response modifiers) as having causal or contributory roles. Among the various medications cited in cases of drug-induced HF, some have been linked to significantly increased risks of stroke, myocardial infarction, and death, particularly in patients with existing cardiovascular (CV) disorders or CV risk factors. In recent years, postmarketing and surveillance data have linked a number of newer medications--including the antiarrhythmic dronedarone, the antifungal itraconazole, and the anti-cancer drugs trastuzumab, lapatinib, and bevacizumab--to serious cardiac effects not reported during clinical trials.

CONCLUSION

A variety of agents have been associated with drug-induced HF. Patients receiving agents that have been implicated in cases of new-onset HF or exacerbations of HF should be monitored for signs and symptoms of CV effects.

Antiangiogenic therapy for advanced renal cell carcinoma: management of treatment-related toxicities

Treatment of metastatic renal cell carcinoma (mRCC) has evolved rapidly over the last two decades as major pathways involved in pathogenesis have been elucidated. These include the vascular endothelial growth factor (VEGF) axis and mammalian target of rapamycin (mTOR). Therapies targeting the VEGF pathway include bevacizumab, sorafenib, sunitinib, pazopanib, and axitinib, whereas temsirolimus and everolimus inhibit the mTOR pathway. All of these novel therapies—VEGF and mTOR inhibitors—are associated with a variety of unique toxicities, some of which may necessitate expert medical management, treatment interruption, or dose reduction. Common adverse events with newer drugs include hypertension, skin reactions, gastrointestinal disturbances, thyroid dysfunction, and fatigue. Skilled management of these toxicities is vital to ensure optimal therapeutic dosing and maximize patient outcomes, including improved survival and quality of life. This review describes and compares the toxicity profiles of novel molecularly targeted agents used in the treatment of mRCC and presents guidance on how best to prevent and manage treatment-related toxicities. Particular attention is given to axitinib, the newest agent to enter the armamentarium. Axitinib is a second-generation receptor tyrosine kinase inhibitor with potent VEGF receptor inhibition that provides durable responses and superior progression-free survival in advanced RCC compared with sorafenib.

Phase II trial of sunitinib in patients with metastatic non-clear cell renal cell carcinoma

Sunitinib is associated with a robust objective response rate in patients with metastatic clear cell renal cell carcinoma (RCC). The primary objective of this phase II clinical trial was to assess the overall response rate for sunitinib in patients with papillary metastatic RCC as well as other non-clear cell histologies. A Simon 2-stage design was used to determine the number of papillary metastatic RCC patients for enrollment, and allowed for descriptive response data for other non-clear cell histologies. Twenty-three patients were enrolled, including 8 with papillary renal cell carcinoma (RCC) and the remainder with other non-clear cell histologies (unclassified in 5 patients). All patients received 50 mg of oral sunitinib in cycles of 4 weeks followed by 2 weeks of rest (4/2). The trial was stopped early because of slow accrual; no responses were observed in the 8 patients with papillary RCC. In the 22 evaluable patients, best response to sunitinib included a partial response in 1 patient with unclassified RCC, stable disease in 15, and progression in 6. The median progression-free survival was 5.5 months (95% CI, 2.5-7.1) in all 23 patients, and 5.6 months for the 8 papillary patients (95% CI, 1.4-7.1). The robust objective responses sunitinib had produced in clear cell RCC could not be demonstrated in this study comprised of patients with non-clear cell histologies.

Adjuvant and neoadjuvant therapy for renal cell carcinoma: a survey of the Society of Urologic Oncology

OBJECTIVE

Several systemic agents have been approved for patients with advanced renal cell carcinoma (RCC) and others are in various stages of development. We surveyed members of the Society of Urologic Oncology (SUO) regarding the importance of adjuvant and neoadjuvant systemic therapy for RCC and their participation in such trials.

MATERIALS AND METHODS

A survey was sent in October 2010 to 564 U.S. and Canadian members of the SUO and the SUO-Clinical Trials Committee with a valid e-mail address. A total of 136 urologic cancer specialists from a mixture of practice patterns responded to the questionnaire (24% participation rate).

RESULTS

At the time of the study, 75% participated in adjuvant or neoadjuvant treatment protocols, including 75% with adjuvant and 16% with neoadjuvant protocols. There was universal support for continued investigation of agents for adjuvant use in RCC with locoregional metastasis (100%) and nearly universal support for investigation of agents in patients with "high risk" (99%) and "intermediate risk" (91%) localized RCC after nephrectomy. The vast majority of respondents also supported investigation of neoadjuvant therapies in patients with advanced RCC (98%) or locally-advanced RCC (98%), with 70% also supporting neoadjuvant trials in patients with localized RCC. Importantly, 98% of respondents indicated interest in participating in future adjuvant and neoadjuvant trials.

CONCLUSION

Urologic cancer specialists surveyed in late 2010 demonstrated nearly universal support for trials to investigate the role of neoadjuvant and adjuvant therapies for RCC of all stages. With appropriate patient selection and outcome assessment, this widespread support indicates great potential for future clinical trials which will require the participation of urologic surgeons.

Predictors of response to targeted therapy in renal cell carcinoma

CONTEXT

The prognosis for patients with metastatic renal cell carcinoma is poor, with an average 5-year survival of approximately 10%. Use of traditional cytokine therapy, specifically high-dose interleukin 2, is limited by significant toxicity. Better understanding of the molecular pathogenesis of renal cell carcinoma has led to the development of targeted therapies to inhibit specific cellular pathways leading to tumorigenesis. These drugs provide improved survival with a more favorable toxicity profile. There is ongoing investigation of markers that predict response of an individual patient to different targeted therapies.

OBJECTIVE

To explain the molecular basis for vascular endothelial growth factor inhibitor (antiangiogenic) and mammalian target of rapamycin inhibitor therapies for renal cell carcinoma, summarize the clinical trials demonstrating the effectiveness of these drugs, and describe the biomarkers shown to correlate with outcome in patients treated with targeted therapy.

DATA SOURCES

All included sources are from peer-reviewed journals in PubMed (US National Library of Medicine).

CONCLUSION

Emerging evidence shows promise that biomarkers will be useful for predicting an individual patient's response to targeted therapy, leading to a more personalized approach to treating renal cell carcinoma.

Targeting cancer with small-molecular-weight kinase inhibitors

Protein and lipid kinases fulfill essential roles in many signaling pathways that regulate normal cell functions. Deregulation of these kinase activities lead to a variety of pathologies ranging from cancer to inflammatory diseases, diabetes, infectious diseases, cardiovascular disorders, cell growth and survival. 518 protein kinases and about 20 lipid-modifying kinases are encoded by the human genome, and a much larger proportion of additional kinases are present in parasite, bacterial, fungal, and viral genomes that are susceptible to exploitation as drug targets. Since many human diseases result from overactivation of protein and lipid kinases due to mutations and/or overexpression, this enzyme class represents an important target for the pharmaceutical industry. Approximately one third of all protein targets under investigation in the pharmaceutical industry are protein or lipid kinases.The kinase inhibitors that have been launched, thus far, are mainly in oncology indications and are directed against a handful of protein and lipid kinases. With one exception, all of these registered kinase inhibitors are directed toward the ATP-site and display different selectivities, potencies, and pharmacokinetic properties. At present, about 150 kinase-targeted drugs are in clinical development and many more in various stages of preclinical development. Kinase inhibitor drugs that are in clinical trials target all stages of signal transduction from the receptor protein tyrosine kinases that initiate intracellular signaling, through second-messenger-dependent lipid and protein kinases, and protein kinases that regulate the cell cycle.This review provides an insight into protein and lipid kinase drug discovery with respect to achievements, binding modes of inhibitors, and novel avenues for the generation of second-generation kinase inhibitors to treat cancers.

Microvascular density as an independent predictor of clinical outcome in renal cell carcinoma: an automated image analysis study

Tumor microvascular density (MVD) has been shown to correlate with the aggressiveness of several cancers. With the introduction of targeted anti-angiogenic therapy, assessment of MVD has the potential not only as a prognostic but also as a therapeutic marker. The significance of tumor vascularity in clear cell renal cell carcinoma (ccRCC) has been debated, with studies showing contradictory results. Previous studies were limited by manual quantification of MVD within a small area of tumor. Since then, the validity of this method has been questioned. To avoid the inaccuracies of manual quantification, we employed a computerized image analysis, which allowed assessment of large areas of tumor and adjacent normal tissue. The latter was used as an internal reference for normalization. MVD and vascular endothelial growth factor (VEGF) were assessed in 57 cases of ccRCC. Sections were immunostained for CD34 and VEGF. Areas of ccRCC and normal kidney medulla were analyzed within scanned images using software that counted CD34-positive vessels and measured the intensity of VEGF staining. We obtained unadjusted values from tumoral areas and calculated adjusted values as tumor/normal ratios. Unadjusted MVD had no association with clinical outcome. However, similarly to tumor stage, higher adjusted MVD was associated with shorter disease-free survival (log-rank P=0.037, Cox P=0.02). This was significant in univariate and multivariate analyses. MVD did not correlate with tumor stage, pointing to its independent prognostic value. As expected due to the known molecular abnormalities in ccRCC, most tumors showed higher VEGF expression than normal tissue. Higher adjusted VEGF was associated with high tumor grade (P=0.049). The finding of increased MVD as an independent marker of tumor aggressiveness may prove useful in the development of new tests for prognostic and therapeutic guidance. Digital techniques can provide more accurate assessment of immunomarkers and may reveal less obvious associations.

A case of metastatic renal cell carcinoma treated effectively by gemcitabine and sunitinib

A 60-year-old man with renal cell carcinoma developed lung metastases after treatment with left radical nephrectomy (pT3bN0M0, clear cell renal carcinoma, Fuhrman G3 >2). The patient received treatment with gemcitabine and interferon-α and achieved complete response after seven cycles of therapy. However, eight months later, local recurrence was discovered in the renal fossa. We changed the therapeutic strategy to sunitinib, a multi-target tyrosine kinase inhibitor. The patient achieved a complete response after twelve cycles of therapy. This case report illustrates the effective use of gemcitabine and sunitinib sequentially for a patient with metastatic renal cell carcinoma.

VEGF pathway-targeted therapy for advanced renal cell carcinoma: a meta-analysis of randomized controlled trials

Immunotherapy which has been in practice for more than 20 years proves effective for the treatment of metastatic renal cell carcinoma (mRCC). Anti-angiogenesis-targeted therapy has recently been identified as a promising therapeutic strategy for mRCC. This study was aimed to evaluate the effectiveness of vascular endothelial growth factor (VEGF) pathway-targeted therapy for mRCC by comparing its effectiveness with that of immunotherapy. The electronic databases were searched. Randomized controlled trials (RCTs) on comparison of VEGF inhibiting drugs (sorafenib, sunitinib and bevacizumab) with interferon (IFN) or placebo for mRCC treatment were included. Data were pooled to meta-analyze. A total of 7 RCTs with 3451 patients were involved. The results showed that anti-VEGF agents improved progression-free survival (PFS) and offered substantial clinical benefits to patients with mRCC. Among them, sunitinib had a higher overall response rate (ORR) than IFN (47% versus 12%, P<0.000001). Bevacizumab plus IFN produced a superior PFS [risk ratio (RR): 0.86, 95% confidence interval (CI): 0.76-0.97; P=0.01] and ORR (RR: 2.19; 95% CI: 1.72-2.78; P<0.00001) in patients with mRCC over IFN, but it yielded an increase by 31% in the risk of serious toxic effects (RR: 1.31; 95% CI: 1.20-1.43; P<0.00001) as compared with IFN. The overall survival (OS) was extended by sorafenib (17.8 months) and sunitinib (26.4 months) as compared with IFN (13 months). It was concluded that compared with IFN therapy, VEGF pathway-targeted therapies improved PFS and achieved significant therapeutic benefits in mRCC. However, the risk to benefit ratio of these agents needs to be further evaluated.

Adjuvant and neoadjuvant therapies in high-risk renal cell carcinoma

The standard of care for renal cell carcinoma (RCC) is surgical resection as a monotherapy or as part of a multimodal approach. A significant number of patients undergoing surgery for localized RCC experience recurrence, suggesting that there are some individuals in whom surgical excision is necessary but insufficient because of the presence of micrometastatic disease at diagnosis. This review summarizes current algorithms used to identify patients at high risk for disease recurrence following the surgical resection of RCC, the outcomes of contemporary adjuvant systemic therapy trials, and the rationale supporting the use of neoadjuvant therapy.