Sunitinib in patients with metastatic renal cell carcinoma

The role of antiangiogenesis therapy: bevacizumab and beyond

The importance of angiogenesis in tumour growth and development is well known. Overexpression of vascular endothelial growth factor (VEGF), the key mediator of angiogenesis, is associated with poor prognosis in cancer. As a result, several therapeutic agents that inhibit the actions of VEGF or its receptors are currently in development for use in advanced solid tumours, such breast, colorectal, lung and renal cancer. Clinical data from trials of anti-VEGF agents in this group of tumours are discussed, with a particular focus on the efficacy and safety of bevacizumab, the anti-VEGF agent at the most advanced stage of development in those tumour types. Future potential uses of bevacizumab in cancer therapy will be discussed.

Efficacy and safety of pazopanib in patients with metastatic renal cell carcinoma

PURPOSE

Inactivation of the von Hippel-Lindau gene in clear-cell renal cell carcinomas (RCC) leads to overexpression of hypoxia inducible factor, a transcription factor regulating vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) gene expression. Pazopanib, an angiogenesis inhibitor targeting VEGF receptor, PDGF receptor, and c-KIT, was evaluated in patients with RCC.

PATIENTS AND METHODS

This phase II study was designed as a randomized discontinuation study but was revised to an open-label study on the recommendation of the data monitoring committee (based on week 12 response rate [RR] of 38% in the first 60 patients). The primary end point was changed from progressive disease rate at 16 weeks postrandomization to RR. Pazopanib 800 mg was administered orally once daily. Pazopanib 800 mg was administered orally once daily.

RESULTS

The study enrolled 225 patients with metastatic RCC; 155 patients (69%) were treatment naïve, and 70 patients (31%) had received one prior cytokine- or bevacizumab-containing regimen. Overall RR was 35%; median duration of response was 68 weeks. Median progression-free survival (PFS) was 52 weeks. Eastern Cooperative Oncology Group performance status of 0 and time from diagnosis to treatment of more than 1 year were correlated with prolonged PFS. Pazopanib was generally well tolerated. The most common adverse events were diarrhea, fatigue, and hair depigmentation. The most common laboratory abnormalities were elevated AST and ALT.

CONCLUSION

Pazopanib demonstrated durable activity in patients with advanced RCC and was generally well tolerated in this population. These findings support the further development of pazopanib in advanced RCC.

Interferon-gamma is induced in human peripheral blood immune cells in vitro by sodium stibogluconate/interleukin-2 and mediates its antitumor activity in vivo

Sodium stibogluconate (SSG), an inhibitor of SHP-1 that negatively regulates cytokine signaling and immunity, suppressed growth of murine Renca tumors in combination with interleukin-2 (IL-2) via a T-cell-dependent mechanism. The ability of SSG to interact with IL-2 in activating primary human immune cells was evaluated herein by assessing its induction of interferon (IFN)-gamma(+) TH1 cells in human peripheral blood in vitro. The significance of IFN-gamma(+) cells was also investigated by assessing SSG/IL-2 antitumor activity in wild-type and IFN-gamma(-/-) mice. IFN-gamma(+) cells but not IL-5(+) cells were induced markedly (9.1x) in healthy peripheral blood by SSG/IL-2 in contrast to the modest induction by SSG alone (2.1x) at its clinically achievable dose (20 microg/mL) or by IL-2 (3.1x) at its C(max) of low-dose schedule (30 IU/mL). SSG at a higher dose (100 microg/mL) was less effective alone (1.5x) or in combination with IL-2 (7.8x). Peripheral IFN-gamma(+) cells were induced after 4 or 16 h treatment with SSG/IL-2 within CD4(+) and CD8(+) lymphocytes coincided with heightened CD69 expression (approximately 3-4x). SSG/IL-2 was also more effective than the single agents in inducing IFN-gamma(+) cells in the peripheral blood of melanoma patients, whose basal IFN-gamma(+) cell levels were approximately 5% of healthy controls. Renca tumor growth was inhibited by SSG/IL-2 in wild-type but not IFN-gamma(-/-) mice. These results demonstrate SSG interactions with IL-2 in vitro to activate key antitumor immune cells in peripheral blood of healthy and melanoma donors, providing further evidence for proof of concept clinical trials for effecting augmentation of IL-2 through inhibiting negative regulatory protein tyrosine phosphatases.

Potential use of circulating endothelial cells as a biomarker of renal cell carcinoma

Each year, renal cell carcinoma (RCC) accounts for significant mortality in the population. Whilst the disease is now being diagnosed earlier, determining patient prognosis remains a challenge. Current prognostic indicators, such as TNM stage, Fuhrman grade, and RCC subtype, are inadequate. Unlike several other malignancies, RCC lacks a biomarker that can stratify patients into high, intermediate, or low risk for developing metastases. Additionally, antiangiogenic therapy is currently offered to patients with metastatic disease, however, a biomarker to monitor treatment efficacy is lacking. Recent attention has focused on surrogate markers of tumor vascularization as a source of prognostic biomarkers, as tumor growth is ultimately dependent on neovascularization. Two cell populations of interest, circulating endothelial cells (CECs) and circulating endothelial progenitors (CEPs), have been demonstrated across several studies to contribute to tumor vascularization. Given these findings, studies have examined their utility as biomarkers of prognosis by correlating their levels with progression-free survival and prognostic determinants such as tumor volume and weight. However, their role in predicting prognosis in RCC, as well as their potential to act as markers of treatment efficacy in metastatic RCC, remains to be established. Previous studies on CECs and CEPs in the context of cancer will be outlined in this review.

Targeted therapies in non-muscle-invasive bladder cancer according to the signaling pathways

With 300,000 annually new cases worldwide, urothelial-cell carcinoma of the bladder (UCCB) is the second most common urologic neoplasm after prostate carcinoma. Non-muscle-invasive bladder cancer (NMIBC), which is not immediately life-threatening, represents 70% to 80% of these initial cases. Despite optimal treatment (transurethral resection with intravesical chemo- or immunotherapy), 70% of these NMIBC will recur, and 10% to 20% will progress, highlighting the need for a new therapeutic approach. Indeed, the identification of patients at high risk of disease recurrence and progression would be beneficial in predicting which patients with NMIBC would benefit from strict follow-up and which would benefit from a more aggressive therapy. To date, conventional treatment remains disappointing in terms of oncologic results and morbidity. The growing understanding in tumor biology has enabled the signaling pathways involved in bladder tumorigenesis and progression to be identified, but few molecular targets have been available until now. The encouraging results seen in various human carcinomas suggests that these new agents should become part of the arsenal of drugs available in the treatment of NMIBC, alone or in combination with already known agents. In this article, we have tried to highlight the main molecular signaling pathways involved in NMIBC tumorigenesis and progression, and the potential targets useful for improving the treatment of NMIBC.

A phase II study of sunitinib in Japanese patients with metastatic renal cell carcinoma: insights into the treatment, efficacy and safety

OBJECTIVE

This study aims to assess the efficacy and safety of sunitinib in Japanese patients with metastatic renal cell carcinoma (RCC).

METHODS

Fifty-one Japanese patients with prior nephrectomy, 25 treatment-naive patients (first-line group) and 26 cytokine-refractory patients (pretreated group) were enrolled in this phase II trial. Patients received sunitinib 50 mg orally, once daily, in repeated 6-week cycles (4 weeks on treatment, 2 weeks off). The primary endpoint was RECIST-defined objective response rate (ORR) with tumour assessments every 6 weeks via computed tomography or magnetic resonance imaging. Toxicity was assessed regularly. In the primary efficacy analysis of the intent-to-treat (ITT) population, ORR and 95% confidence interval were calculated based on independent review. Secondary time-to-event endpoints, such as progression-free survival (PFS), were estimated using the Kaplan-Meier method.

RESULTS

In the ITT population, ORR was 48.0% in the first-line group (after a median 4 cycles), 46.2% in the pretreated group (5 cycles) and 47.1% overall, with median times to tumour response of 7.1, 10.7 and 10.0 weeks, respectively. Median PFS was 46.0, 33.6 and 46.0 weeks, respectively. The most common treatment-related grade 3/4 adverse events and laboratory abnormalities were fatigue (20%), hand-foot syndrome (14%) and hypertension (12%), decreased platelet count (55%), decreased neutrophil count (51%), increased lipase (39%) and decreased lymphocyte count (33%).

CONCLUSIONS

In Japanese patients with RCC, sunitinib is consistently effective and tolerable with similar risk/benefit as that in Western patients, though there was a trend toward greater antitumour efficacy and higher incidence of haematological adverse events in Japanese patients.

Surgery for vena caval tumor extension in renal cancer

PURPOSE OF REVIEW

We review recent efforts designed to improve the preoperative assessment, minimize the surgical morbidity, and develop multimodal treatments for patient with renal cell carcinoma and venous tumor thrombus.

RECENT FINDINGS

The ability of computerized tomography to classify venous thrombus has improved with recent advancements in multidetector/three-dimensional technology. The utility of preoperative imaging to predict vascular wall invasion, which carries adverse prognostic significance, has also been demonstrated. Minimally invasive approaches to low-level thrombus cases have been explored, whereas techniques to minimize the morbidity associated with the use of cardiopulmonary bypass and circulatory arrest in patients with a retrohepatic or supradiaphragmatic thrombus, including antegrade cerebral perfusion, the use of cardiopulmonary bypass with mild hypothermia, and the increased application of veno-venous bypass, have improved perioperative outcomes. Meanwhile, results from several case reports suggest a potential role for neoadjuvant systemic therapy with tyrosine kinase inhibitors prior to resection.

SUMMARY

Improvements in perioperative assessment and surgical technique have decreased the morbidity and improved the outcomes for patients with renal cell carcinoma and venous tumor thrombus. Further investigations of the role for targeted therapies in the management of these complex patients are needed to define the optimal multimodal approach.

Optimizing the size variation threshold for the CT evaluation of response in metastatic renal cell carcinoma treated with sunitinib

BACKGROUND

In metastatic renal cell carcinoma (mRCC), antiangiogenic treatments rarely achieve a reduction of -30% in the sum of longest diameters (SLD) of target lesions required by RECIST for an 'objective response', although they objectively improve progression-free survival (PFS). We sought to determine a threshold for the computed tomography evaluation of these patients' best reflecting patient outcome.

PATIENTS AND METHODS

In 334 mRCC patients treated with sunitinib, we tested thresholds from -45% to +10%. We classified patients as 'responders' when the best relative variation of the sum of longest diameters (DeltaSLD) reached the tested threshold and as 'nonresponders' otherwise. For each tested threshold, the median PFS of the two groups were compared. Receiver operating characteristic (ROC) analysis was also carried out among the 103 patients that progressed during follow-up. Finally, the 'optimal' threshold was retested on an independent cohort of 39 patients.

RESULTS

The DeltaSLD threshold of -10% gave the most significant difference. It divided patients into 256 responders and 78 nonresponders (median PFS 11.1 and 5.6 months). The same -10% threshold was found using the ROC analysis. Results were confirmed on the external validation cohort.

CONCLUSION

A variation of -10% in the SLD accurately and rapidly identifies mRCC patients benefiting from sunitinib.

Phase II study of continuous daily sunitinib dosing in patients with previously treated advanced non-small cell lung cancer

BACKGROUND

Sunitinib malate (SUTENT) has promising single-agent activity given on Schedule 4/2 (4 weeks on treatment followed by 2 weeks off treatment) in advanced non-small cell lung cancer (NSCLC).

METHODS

We examined the activity of sunitinib on a continuous daily dosing (CDD) schedule in an open-label, multicentre phase II study in patients with previously treated, advanced NSCLC. Patients > or =18 years with stage IIIB/IV NSCLC after failure with platinum-based chemotherapy, received sunitinib 37.5 mg per day. The primary end point was objective response rate (ORR). Secondary end points included progression-free survival (PFS), overall survival (OS), 1-year survival rate, and safety.

RESULTS

Of 47 patients receiving sunitinib, one patient achieved a confirmed partial response (ORR 2.1% (95% confidence interval (CI) 0.1, 11.3)) and 11 (23.4%) had stable disease (SD) > or =8 weeks. Five patients had SD>6 months. Median PFS was 11.9 weeks (95% CI 8.6, 14.1) and median OS was 37.1 weeks (95% CI 31.1, 69.7). The 1-year survival probability was 38.4% (95% CI 24.2, 52.5). Treatment was generally well tolerated.

CONCLUSIONS

The safety profile and time-to-event analyses, albeit relatively low response rate of 2%, suggest single-agent sunitinib on a CDD schedule may be a potential therapeutic agent for patients with advanced, refractory NSCLC.

The role of VHL in clear-cell renal cell carcinoma and its relation to targeted therapy

The basic biology underlying the development of clear-cell renal cell carcinoma (ccRCC) is critically dependent on the von Hippel-Lindau gene (VHL), whose protein product is important in the cell's normal response to hypoxia. Aberrations in VHL's function, either through mutation or promoter hypermethylation, lead to accumulation of the transcriptional regulatory molecule, hypoxia-inducible factor alpha (HIFalpha). HIFalpha can then dimerize with HIFbeta and translocate to the nucleus, where it will transcriptionally upregulate a series of hypoxia-responsive genes, including vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and others. Binding of these ligands to their cognate receptors activates a series of kinase- dependent signaling pathways, including the RAF-MEK-ERK and phosphatidylinositol-3 kinase-AKT-mTOR pathways. Targeted agents developed and now approved for use in advanced ccRCC include humanized monoclonal antibodies against VEGF, small-molecule tyrosine kinase inhibitors, and inhibitors of mTOR. Understanding the biology of ccRCC is critical in understanding the current therapy for the disease and in developing novel therapeutics in the future. This review will provide an overview of the genetics of ccRCC, with an emphasis on how this has informed the development of the targeted therapeutics for this disease.

Brain magnetic resonance imaging changes after sorafenib and sunitinib chemotherapy in patients with advanced renal cell and breast carcinoma

OBJECT

The authors report novel imaging findings associated with the treatment of sorafenib (Nexavar) and sunitinib (Sutant), 2 agents used in the treatment of advanced metastatic disease.

METHODS

Patients with renal cell and breast carcinoma metastases to the brain were identified from the prospective database at the Penn State Hershey Medical Center and Penn State Cancer Institute.

RESULTS

Four patients who received sorafenib or sunitinib after surgical or radiosurgical treatment of their metastases were identified from the database. Clinical and/or radiographic changes consisting of seizures and cognitive or motor changes were described, associated with an increase in peritumoral edema and enhancement. These findings were observed to improve with discontinuation of the medications.

CONCLUSIONS

The administration of sorafenib and sunitinib in patients with metastatic breast and renal cell carcinoma may lead to reversible clinical and imaging changes following surgical or radiosurgical treatment of their brain lesions. The authors hypothesize that leakage of the drug across a locally impaired blood-brain barrier contributes to peritumoral edema and inflammation, which may be erroneously interpreted as disease progression.

Disease stabilization of progressive olfactory neuroblastoma (esthesioneuroblastoma) under treatment with sunitinib mesylate

Olfactory neuroblastoma (esthesioneuroblastoma) is a rare neoplasm of the olfactory epithelium in the upper nasal cavity. Here, we report the case of a 69-year-old man who presented with massive progression of a metastatic esthesioneuroblastoma after endonasal resection, functional neck dissection, and radiotherapy of local and distant tumor relapses. After exhaustion of all conventional therapeutic options, we initiated treatment with the oral multityrosinekinase inhibitor sunitinib mesylate. Using this drug, significant improvement of clinical symptoms, disease stabilization, and recovery from Karnofsky index of 40% to 70% could be achieved in the absence of significant adverse drug effects. The patient died 15 months after initiation of sunitinib therapy due to complications of a traumatic femoral neck fracture without evidence of tumor progression. Immunohistochemical analysis of tumor tissue specimens obtained at initial surgery revealed ample expression of platelet-derived growth factor receptor (PDGFR)-b on stromal and endothelial cells. Sunitinib should be considered for palliative therapy of advanced esthesioneuroblastoma.

[Systemic therapy of metastatic renal cell carcinoma: from many options to the therapeutic strategy]

In the last 5 years the paradigms for the treatment of metastatic renal cell cancer have fundamentally changed. Until 2005 systemic therapy was limited to the immunomodulating cytokines interferon-alfa and interleukin-2, in recent years, however, tyrosine kinase inhibitors, mTor inhibitors and monoclonal antibodies have been established for this therapeutic situation. Without validated predictive biomarkers it is currently not possible to select patients who are likely to benefit from a certain therapy. Therefore, most current guidelines stratify the patients into risk groups according to the MSKCC risk score. The resulting treatment algorithm for first-line therapy is limited to these new drugs within all risk groups. Since approval for more tyrosine kinase inhibitors and mTOR inhibitors is currently awaited, the number of treatment options will expand further in the near future. The present paper reviews the present study data and aims to provide practical advice for the treatment of patients suffering from metastatic renal cell cancer.

A phase ii study of gemcitabine and capecitabine in patients with advanced renal cell cancer: Southwest Oncology Group Study S0312

OBJECTIVES

Gemcitabine plus capecitabine has moderate efficacy in patients with advanced renal cell cancer (RCC) but has considerable toxicity. We evaluated the efficacy and toxicity of a modified dose-schedule of this doublet in patients with metastatic RCC.

METHODS

Chemotherapy-naive patients were treated with gemcitabine at 900 mg/m2 on days 1, 8, and 15 and with capecitabine at 625 mg/m2 twice daily on days 1 through 21, and every 28 days thereafter. The primary end point was response rate (RR). No further evaluation of this regimen would be pursued if the RR was ≤ 5%. In an exploratory analysis, we also evaluated potential markers of prognosis and treatment response, including thymidylate synthase, PTEN, pAKT, pmTOR, XRCC1, and ERCC1.

RESULTS

Of 43 patients, 1 was ineligible and 2 were not analyzable. There was 1 complete response and 3 partial responses, for an overall RR of 10% (95% CI = 3, 24). Nineteen patients (48%) had stable disease. The 6-month freedom-from-treatment-failure and overall survival rates were 20% (95% CI = 8, 32) and 75% (95% CI = 62, 88), respectively. Median survival time was 23 months (95% CI = 10, 37). One patient each experienced grade 4 neutropenia, fatigue, thrombocytopenia, and hemolysis with renal failure. The most common grade 3 toxicities were neutropenia (12 patients), fatigue (5), and leucopenia (4). Patients with a best response of stable disease or better were more likely to have decreased expression of PTEN and increased expression of pmTOR.

CONCLUSIONS

Gemcitabine plus capecitabine at this reduced dose-schedule benefits a small percentage of patients with RCC with an acceptable toxicity profile.

Relationship between tumor-infiltrating T lymphocytes and clinical response after reduced-intensity allogeneic hematopoietic stem cell transplantation for advanced renal cell carcinoma: a single center prospective study

OBJECTIVE

Renal cell carcinoma (RCC) is refractory to conventional therapy, including chemotherapy and radiation. However, because RCC is sensitive to cytokine therapy, an immunotherapeutic approach such as hematopoietic stem cell transplantation (HSCT) might lead to a cure. We performed an institutional clinical study of HSCT for refractory RCC patients.

METHODS

RCC patients aged 50 years or over, refractory to therapy, were eligible for the study. HSCT was performed after reduced-intensity conditioning. Primary endpoint was defined as the survival at day 100 after HSCT with complete donor chimerism, and secondary endpoint was the effectiveness of HSCT.

RESULTS

Seven patients, provided with written informed consent, were enrolled in the study. Six of the seven patients achieved complete donor chimera at day 30 after HSCT, but one patient received second HSCT because of graft rejection. Four patients achieved a partial response (PR) and stable disease was observed in another patient, but these responses were temporary. The disease of the other two patients became progressive. Autopsy findings revealed an accumulation of CD8(+) lymphocytes and degenerative changes in the local RCC lesion in three of six patients who responded clinically. An autopsy of a patient who had obtained a PR revealed lymphocyte involvement with a cytotoxic T cell (CTL) phenotype in the metastasis of RCC.

CONCLUSIONS

Our results demonstrate the efficacy of HSCT for RCC and suggest that the graft-versus-tumor effect elicited by CTLs is induced in vivo. HSCT should be further explored as a potential curative treatment for RCC.

A phase I study of sunitinib plus bevacizumab in advanced solid tumors

PURPOSE

Bevacizumab is an antibody against vascular endothelial growth factor; sunitinib is an inhibitor of vascular endothelial growth factor and related receptors. The safety and maximum tolerated dose of sunitinib plus bevacizumab was assessed in this phase I trial.

EXPERIMENTAL DESIGN

Patients with advanced solid tumors were treated on a 3+3 trial design. Patients received sunitinib daily (starting dose level, 25 mg) for 4 weeks on followed by 2 weeks off and bevacizumab (starting dose level, 5 mg/kg) on days 1, 15, and 29 of a 42-day cycle. Dose-limiting toxicities during the first 6-week cycle were used to determine the maximum tolerated dose.

RESULTS

Thirty-eight patients were enrolled. Patients received a median of 3 cycles of treatment (range, 1-17(+)). There was one dose-limiting toxicity (grade 4 hypertension) at 37.5 mg sunitinib and 5 mg/kg bevacizumab. Grade 3 or greater toxicity was observed in 87% of patients including hypertension (47%), fatigue (24%), thrombocytopenia (18%), proteinuria (13%), and hand-foot syndrome (13%). Dose modifications and delays were common at higher dose levels. No clinical or laboratory evidence of microangiopathic hemolytic anemia was observed. Seven patients had a confirmed Response Evaluation Criteria in Solid Tumors-defined partial response (18%; 95% confidence interval, 8-34%). Nineteen of the 32 patients with a postbaseline scan (59%) had at least some reduction in overall tumor burden (median, 32%; range, 3-73%).

CONCLUSIONS

The combination of sunitinib and bevacizumab in patients with advanced solid tumors is feasible, albeit with toxicity at higher dose levels and requiring dose modification with continued therapy. Antitumor activity was observed across multiple solid tumors.

Ambulatory monitoring detects sorafenib-induced blood pressure elevations on the first day of treatment

PURPOSE

Hypertension is a mechanism-based toxicity of sorafenib and other cancer therapeutics that inhibit the vascular endothelial growth factor (VEGF) signaling pathway. This prospective, single-center, cohort study characterized ambulatory blood pressure monitoring as an early pharmacodynamic biomarker of VEGF signaling pathway inhibition by sorafenib.

EXPERIMENTAL DESIGN

Fifty-four normotensive advanced cancer patients underwent 24-hour ambulatory blood pressure monitoring before and between days 6 and 10 of sorafenib therapy. After blood pressure changes were detected among the first cohort within 10 days, ambulatory blood pressure monitoring was done during the first 24 hours of treatment for the second cohort.

RESULTS

For the entire patient population, the blood pressure increase [mean systolic, +10.8 mm Hg; 95% confidence interval (95% CI), 8.6-13.0; range, -5.2 to +28.7 mm Hg; mean diastolic, +8.0 mm Hg; 95% CI, 6.3-9.7; range, -4.4 to +27.1 mm Hg] was detected between days 6 and 10 (P < 0.0001 for both) and plateaued thereafter. Variability in blood pressure change did not associate with: age, body size, sex, self-reported race, baseline blood pressure, or steady-state sorafenib plasma concentrations. In the second cohort, the blood pressure elevation was detected during the first 24 hours (mean systolic, +8.2 mm Hg; 95% CI, 5.0-11.3; mean diastolic, +6.5 mm Hg; 95% CI, 4.7-8.3; P < 0.0001 for both).

CONCLUSIONS

Ambulatory blood pressure monitoring detects the blood pressure response to VEGF signaling pathway inhibition by sorafenib during the first 24 hours of treatment. The magnitude of blood pressure elevation is highly variable and unpredictable but could be important in optimizing the therapeutic index of VEGF signaling pathway inhibitor therapy.

UK guidelines for the systemic treatment of renal cell carcinoma

There have been recent significant improvements in treatment options for patients with advanced renal cell carcinoma. This article presents UK consensus guidelines on the use of systemic therapies for this poor prognosis disease.

Increased hemoglobin associated with VEGF inhibitors in advanced renal cell carcinoma

We retrospectively analyzed whether increased hemoglobin is a surrogate biomarker of efficacy for vascular endothelial growth factor (VEGF) inhibitors in advanced renal cell carcinoma (RCC) patients. Twelve patients were identified who had received bevacizumab alone or as combination therapy. Eleven patients experienced a rise in hemoglobin. Median change was 1.6 g/dL (0-4.0). Degree of peak increase correlated with longer progression-free survival (PFS) in metastatic patients: increase of < 15% yielded a 3.1-month median PFS compared to 8.2 months with rises > 15%. This study identifies increased hemoglobin as a possible consequence of VEGF inhibitors. The correlation with longer PFS suggests that rise in hemoglobin may be a surrogate biomarker of efficacy.

Economic evaluation of sunitinib malate in second-line treatment of metastatic renal cell carcinoma in Finland

BACKGROUND

Cytokine therapy is currently used as first-line treatment of metastatic renal cell carcinoma (mRCC). Until recently, treatments with proven efficacy after the failure of first-line cytokine therapy were not available. In recent clinical trials, sunitinib has been associated with good response rates in patients with mRCC.

OBJECTIVE

The aim of this study was to analyze the cost-effectiveness of sunitinib as second-line therapy for cytokine-refractory mRCC compared with current routine clinical practice in Finland (ie, best supportive care [BSC], including palliative biochemotherapy).

METHODS

A probabilistic decision-analytic model was developed to estimate the cost-effectiveness of sunitinib. Data were gathered from clinical trials, literature sources, and expert opinions, as well as from a local sample (n = 39) from 2 university hospitals in Finland. Clinical experts treating patients with mRCC in Finland provided the information on care practices of prescribing sunitinib. The analysis was conducted from the perspective of the health care payer in Finland.

RESULTS

According to estimated incremental cost-effectiveness ratios (ICERs), 1 progression-free month gained cost euro4802 (2005 Euros); 1 life-year gained cost euro30,831; and 1 quality-adjusted life-year (QALY) gained cost euro43,698, compared with BSC, in the treatment of mRCC. The expected mean cost in BSC was euro5543. When parameter uncertainty was considered, the probability of sunitinib being the more cost-effective choice of treatment was ~70% at the willingness-to-pay level of euro45,000/QALY gained.

CONCLUSIONS

Based on the results of this cost-effectiveness analysis, sunitinib is potentially cost-effective as a second-line treatment of mRCC compared with the treatment currently practiced in Finnish hospitals. The ICER (euro/QALY gained) obtained in the present study was less than the value considered suitable for novel oncology treatments.

Onset of male gynaecomastia in a patient treated with sunitinib for metastatic renal cell carcinoma

Sunitinib is an orally administered multitargeted tyrosine kinase inhibitor that has demonstrated substantial antitumour activity in patients with metastatic renal cell carcinoma. The more common grade 3 or 4 adverse effects of sunitinib include hypertension, fatigue, hand-foot syndrome, elevated lipase and lymphopenia. We report the case of a 69-year-old patient with metastatic renal clear-cell carcinoma, treated with nephrectomy and three lines of therapy (interleukin-2 plus interferon-alpha2a, vinorelbine plus gemcitabine, and capecitabine), who started a fourth-line therapy with oral sunitinib because of disease progression. At the end of his fifth cycle of sunitinib therapy, the patient complained of the development of abnormally large mammary glands associated with pain and peri-areolar erythema. After 2 weeks' off therapy, a partial reduction in mammary gland enlargement, local pain and erythema was observed. However, re-initiation of sunitinib treatment was followed by bilateral breast enlargement again. The mechanism by which sunitinib induces gynaecomastia is thought to be associated with an unknown direct action on breast hormonal receptors. To the best of our knowledge, this is the first report of an association between sunitinib and gynaecomastia.

Pharmacological management of gastrointestinal stromal tumours: an update on the role of sunitinib

The efficacy and tolerability of the receptor tyrosine kinase inhibitor, sunitinib malate, have been demonstrated in phase I-III clinical trials of patients with imatinib-resistant or imatinib-intolerant gastrointestinal stromal tumours (GIST) as well as in a worldwide expanded-access study and in a continuous daily dosing (CDD) trial. Tumour genotype may have a significant influence on the activity of sunitinib in patients with imatinib-resistant GIST. Sunitinib activity was observed across different GIST genotypes and particularly in patients with wild-type and KIT exon 9 mutations (all relatively resistant to standard-dose imatinib) and in patients with secondary KIT exons 13 and 14 mutations. Adverse events with sunitinib were generally mild to moderate and easily managed by dose reduction, dose interruption or standard supportive measures. Treatment discontinuation can be avoided in most patients by close monitoring before and during treatment with appropriate adverse event management as necessary. The correlation between treatment exposure and clinical response is prompting the search for new approaches to treatment optimisation to ensure that patients derive maximum benefit from sunitinib therapy, including dose adjustments based on blood testing to ensure optimal drug exposure, and the use of the alternative CDD regimen to avoid treatment interruption.

Pharmacogenetic pathway analysis for determination of sunitinib-induced toxicity

PURPOSE

To identify genetic markers in the pharmacokinetic and pharmacodynamic pathways of sunitinib that predispose for development of toxicities: thrombocytopenia, leukopenia, mucosal inflammation, hand-foot syndrome, and any toxicity according to National Cancer Institute Common Toxicity Criteria higher than grade 2.

PATIENTS AND METHODS

A multicenter pharmacogenetic association study was performed in 219 patients treated with single-agent sunitinib. A total of 31 single nucleotide polymorphisms in 12 candidate genes, together with several nongenetic variants, were analyzed for a possible association with toxicity. In addition, genetic haplotypes were developed and related to toxicity.

RESULTS

The risk for leukopenia was increased when the G allele in CYP1A1 2455A/G (odds ratio [OR], 6.24; P = .029) or the T allele in FLT3 738T/C (OR, 2.8; P = .008) were present or CAG in the NR1I3 (5719C/T, 7738A/C, 7837T/G) haplotype (OR, 1.74; P = .041) was absent. Any toxicity higher than grade 2 prevalence was increased when the T allele of vascular endothelial growth factor receptor 2 1191C/T (OR, 2.39; P = .046) or a copy of TT in the ABCG2 (-15622C/T, 1143C/T) haplotype (OR, 2.63; P = .016) were present. The risk for mucosal inflammation was increased in the presence of the G allele in CYP1A1 2455A/G (OR, 4.03; P = .021) and the prevalence of hand-foot syndrome was increased when a copy of TTT in the ABCB1 (3435C/T, 1236C/T, 2677G/T) haplotype (OR, 2.56; P = .035) was present.

CONCLUSION

This exploratory study suggests that polymorphisms in specific genes encoding for metabolizing enzymes, efflux transporters, and drug targets are associated with sunitinib-related toxicities. A better understanding of genetic and nongenetic determinants of sunitinib toxicity should help to optimize drug treatment in individual patients.

Phase II study of sunitinib administered in a continuous once-daily dosing regimen in patients with cytokine-refractory metastatic renal cell carcinoma

PURPOSE

Sunitinib has demonstrated antitumor activity in metastatic renal cell carcinoma (mRCC) when given at 50 mg/d on a 4-weeks-on 2-weeks-off regimen. Herein, we report results of an open-label, multicenter phase II mRCC study of sunitinib administered on a continuous once-daily dosing regimen.

PATIENTS AND METHODS

Eligibility criteria included histologically proven mRCC with measurable disease, failure of one prior cytokine regimen, and good performance status. Patients were randomly assigned to a sunitinib starting dose of 37.5 mg/d in the morning (AM) or evening (PM). RECIST-defined objective response rate (ORR) was the primary end point. Secondary end points included progression-free survival (PFS), overall survival (OS), adverse events (AEs), and quality-of-life measures.

RESULTS

One hundred seven patients were randomly assigned to AM (n = 54) or PM (n = 53) dosing and on study for a median 8.3 months. Eighty-three patients discontinued, 65 due to disease progression and 16 because of AEs; two patients withdrew consent. Dosing was reduced to 25 mg/d in 46 patients (43%) due to grade 3/4 AEs. The most common grade 3 treatment-related AEs were asthenia/fatigue (16%), diarrhea (11%), hypertension (11%), hand-foot syndrome (9%), and anorexia (8%). ORR was 20% with a 7.2-month median response duration. Median PFS and OS were 8.2 and 19.8 months, respectively, at median follow-up of 26.4 months. Efficacy, tolerability, and quality-of-life results were similar between patients dosed in the AM or PM.

CONCLUSION

Sunitinib 37.5 mg, administered on a continuous once-daily dosing regimen, has a manageable safety profile as second-line mRCC therapy, providing flexible dosing, which can be explored in combination studies.

Phase II study of axitinib in sorafenib-refractory metastatic renal cell carcinoma

PURPOSE

To investigate the efficacy and safety of axitinib, an oral, potent, and selective inhibitor of vascular endothelial growth factor (VEGF) receptors 1, 2, and 3 in patients with metastatic renal cell carcinoma (mRCC) refractory to prior therapies that included, but were not limited to, sorafenib.

PATIENTS AND METHODS

In this multicenter, open-label, phase II study, patients with sorafenib-refractory mRCC received a starting dose of axitinib 5 mg orally twice daily. A one-arm, single-stage design was used to estimate the primary end point of objective response rate (ORR), defined by RECIST (Response Evaluation Criteria in Solid Tumors). Secondary end points included safety, duration of response, progression-free survival (PFS), overall survival (OS), and patient-reported outcomes.

RESULTS

Of 62 patients recruited, 100% had received prior sorafenib, and 74.2% had received two or more prior systemic treatments. The axitinib dose was titrated to greater than 5 mg twice daily in 53.2% of patients, and 35.5% of patients had the dose modified to less than 5 mg twice daily. In 62 patients evaluable for response, the ORR was 22.6%, and the median duration of response was 17.5 months. Median PFS and OS times were 7.4 months (95% CI, 6.7 to 11.0 months) and 13.6 months (95% CI, 8.4 to 18.8 months), respectively. All-causality grade 3 to 4 adverse events included hand-foot syndrome (16.1%), fatigue (16.1%), hypertension (16.1%), dyspnea (14.5%), diarrhea (14.5%), dehydration (8.1%), and hypotension (6.5%).

CONCLUSION

Axitinib has antitumor activity in patients with mRCC refractory to prior VEGF-targeted therapy, including sorafenib. Toxicities were mild to moderate and were manageable. A randomized, phase III trial to compare axitinib with sorafenib in patients who have mRCC refractory to one prior first-line therapy regimen is underway.

Role of cytoreductive nephrectomy in renal cell carcinoma

Cytoreductive nephrectomy prior to cytokine therapy has a well-established role in the treatment of appropriately selected patients with metastatic renal cell carcinoma (RCC). Recent use of novel molecular targeted agents in the management of metastatic RCC has challenged the current dogma of treatment with regards to the necessity, patient selection for and timing of cytoreductive nephrectomy. Current evidence suggests that cytoreductive nephrectomy still plays an integral part in the multimodal paradigm of management for metastatic RCC. This review highlights the role of cytoreductive nephrectomy, and discusses controversial issues surrounding cytoreductive nephrectomy in the treatment of metastatic RCC, in the context of immunotherapy and also in the new era of targeted therapy. It also gives updates on the changing concepts of surgical approaches to cytoreductive nephrectomy in metastatic RCC.

Overall survival and updated results for sunitinib compared with interferon alfa in patients with metastatic renal cell carcinoma

PURPOSE

A randomized, phase III trial demonstrated superiority of sunitinib over interferon alfa (IFN-alpha) in progression-free survival (primary end point) as first-line treatment for metastatic renal cell carcinoma (RCC). Final survival analyses and updated results are reported.

PATIENTS AND METHODS

Seven hundred fifty treatment-naïve patients with metastatic clear cell RCC were randomly assigned to sunitinib 50 mg orally once daily on a 4 weeks on, 2 weeks off dosing schedule or to IFN-alpha 9 MU subcutaneously thrice weekly. Overall survival was compared by two-sided log-rank and Wilcoxon tests. Progression-free survival, response, and safety end points were assessed with updated follow-up.

RESULTS

Median overall survival was greater in the sunitinib group than in the IFN-alpha group (26.4 v 21.8 months, respectively; hazard ratio [HR] = 0.821; 95% CI, 0.673 to 1.001; P = .051) per the primary analysis of unstratified log-rank test (P = .013 per unstratified Wilcoxon test). By stratified log-rank test, the HR was 0.818 (95% CI, 0.669 to 0.999; P = .049). Within the IFN-alpha group, 33% of patients received sunitinib, and 32% received other vascular endothelial growth factor-signaling inhibitors after discontinuation from the trial. Median progression-free survival was 11 months for sunitinib compared with 5 months for IFN-alpha (P < .001). Objective response rate was 47% for sunitinib compared with 12% for IFN-alpha (P < .001). The most commonly reported sunitinib-related grade 3 adverse events included hypertension (12%), fatigue (11%), diarrhea (9%), and hand-foot syndrome (9%).

CONCLUSION

Sunitinib demonstrates longer overall survival compared with IFN-alpha plus improvement in response and progression-free survival in the first-line treatment of patients with metastatic RCC. The overall survival highlights an improved prognosis in patients with RCC in the era of targeted therapy.

Cost implications of IV versus oral anti-angiogenesis therapies in patients with advanced renal cell carcinoma: retrospective claims database analysis

OBJECTIVE

Angiogenesis inhibitors (AI) are promising novel treatments for patients with renal cell carcinoma (RCC). However, IV therapy may impose infection risk from IV catheters, and will include increased costs due to administration and transportation costs. This study evaluated the incremental costs associated with IV administration of selected AI therapies (bevacizumab off-label) compared to oral therapies (sunitinib or sorafenib) for the treatment of RCC.

METHODS

Patients with > or =2 RCC claims (ICD-9: 189.0, 198.0) were identified from a US commercial health insurance claims database from 1/2004 to 12/2007. Patients receiving bevacizumab (n = 109) were matched 1:1 to patients receiving sorafenib or sunitinib, and observed from their first AI therapy claim until the last treatment date. AI, inpatient, outpatient and pharmacy costs were calculated on a per-patient per-month (PPPM) basis over the treatment period. Costs were compared between the IV AI group and each separate oral AI group using multivariate Tobit regressions for each category separately, adjusting for demographic and baseline clinical characteristics. This study assessed costs of treatment and did not evaluate the cost-effectiveness of AIs.

RESULTS

Mean total medical costs were $13,351, $6998, and $8213 PPPM for bevacizumab, sorafenib, and sunitinib, respectively (p <0.05 for equality). Adjusted incremental total cost for the bevacizumab group was $4951 PPPM compared to sorafenib and $4610 PPPM compared to sunitinib (both p < 0.05). Bevacizumab patients incurred incremental PPPM outpatient services cost compared to sorafenib and sunitinib of $2772 and $2548, respectively (both p < 0.05).

CONCLUSIONS

Assuming median progression-free survival of 8.5 months as shown for bevacizumab (Bukowski, et al., J Clin Oncol 2007), the incremental costs would be estimated at $39 188-42 080 per patient compared to those treated with sunitinib or sorafenib. Assuming similar efficacies, oral AI therapies may result in cost savings to patients and healthcare payers over IV therapies.

Surgical resection of renal cell carcinoma after targeted therapy

PURPOSE

The development of targeted agents for renal cell carcinoma has renewed interest in consolidative surgery due to the robust clinical responses seen with these agents. The integration of targeted therapy and surgery requires careful consideration due to the potential for increased perioperative morbidity.

MATERIALS AND METHODS

We retrospectively identified patients with renal cell carcinoma treated with sunitinib, sorafenib or bevacizumab plus interleukin-2 before tumor resection.

RESULTS

Between June 2005 and August 2008, 19 patients were treated with targeted therapy and subsequently underwent resection. Surgical extirpation involved an open and a laparoscopic approach in 18 and 3 cases, respectively, for locally advanced (8), locally recurrent (6) and metastatic disease (3). Two patients with extensive bilateral renal cell carcinoma were also treated to downsize the tumors to enable partial nephrectomy. Perioperative complications were noted in 16% of patients. One patient had a significant intraoperative hemorrhage and disseminated intravascular coagulopathy from a concomitant liver resection. An anastomotic bowel leak and abscess were noted postoperatively in another patient who underwent en bloc resection of a retroperitoneal recurrence and adjacent colon. Two patients (11%) had minor wound complications, including a wound seroma and a ventral hernia. Pathological analysis of 20 specimens revealed clear cell, chromophobe and unclassified renal cell carcinoma in 80%, 5% and 10% of cases, respectively. One patient (5%) had a pathological complete response.

CONCLUSIONS

Surgical resection of renal cell carcinoma after targeted therapy is feasible with low morbidity in most patients. However, significant complications can occur, raising concern for possible compromise of tissue and/or vascular integrity associated with surgery in this setting.

Safety and efficacy of sunitinib for metastatic renal-cell carcinoma: an expanded-access trial

BACKGROUND

Results from clinical trials have established sunitinib as a standard of care for first-line treatment of advanced or metastatic renal-cell carcinoma (RCC); however, many patients, particularly those with a poorer prognosis, do not meet inclusion criteria and little is known about the activity of sunitinib in these subgroups. The primary objective of this trial was to provide sunitinib on a compassionate-use basis to trial-ineligible patients with RCC from countries where regulatory approval had not been granted.

METHODS

Previously treated and treatment-naive patients at least 18 years of age with metastatic RCC were eligible. All patients received open-label sunitinib 50 mg orally once daily on schedule 4-2 (4 weeks on treatment, 2 weeks off). Safety was assessed regularly, tumour measurements done per local practice, and survival data collected where possible. Analyses were done in the modified intention-to-treat (ITT) population, which consisted of all patients who received at least one dose of sunitinib. This study is registered with ClinicalTrials.gov, NCT00130897.

FINDINGS

As of December, 2007, 4564 patients were enrolled in 52 countries. 4371 patients were included in the modified ITT population. This population included 321 (7%) patients with brain metastases, 582 (13%) with Eastern Cooperative Oncology Group (ECOG) performance status of 2 or higher, 588 (13%) non-clear-cell RCC, and 1418 (32%) aged 65 years or more. Patients received a median of five treatment cycles (range 1-25). Reasons for discontinuation included lack of efficacy (n=1168 [27%]) and adverse events (n=362 [8%]). The most common treatment-related adverse events were diarrhoea (n=1936 [44%]) and fatigue (n=1606 [37%]). The most common grade 3-4 adverse events were fatigue (n=344 [8%]) and thrombocytopenia (n=338 [8%]) with incidences of grade 3-4 adverse events similar across subgroups. In 3464 evaluable patients, the objective response rate (ORR) was 17% (n=603), with subgroup ORR as follows: brain metastases (26 of 213 [12%]), ECOG performance status 2 or higher (29 of 319 [9%]), non-clear-cell RCC (48 of 437 [11%]) and age 65 years or more (176 of 1056 [17%]). Median progression-free survival was 10.9 months (95% CI 10.3-11.2) and overall survival was 18.4 months (17.4-19.2).

INTERPRETATION

In a broad population of patients with metastatic RCC, the safety profile of sunitinib 50 mg once-daily (initial dose) on schedule 4-2 was manageable and efficacy results were encouraging, particularly in subgroups associated with poor prognosis who are not usually entered into clinical trials.

FUNDING

Pfizer Inc.

Molecular fingerprinting of radiation resistant tumors: can we apprehend and rehabilitate the suspects?

Radiation therapy continues to be one of the more popular treatment options for localized prostate cancer. One major obstacle to radiation therapy is that there is a limit to the amount of radiation that can be safely delivered to the target organ. Emerging evidence suggests that therapeutic agents targeting specific molecules might be combined with radiation therapy for more effective treatment of tumors. Recent studies suggest that modulation of these molecules by a variety of mechanisms (e.g., gene therapy, antisense oligonucleotides, small interfering RNA) may enhance the efficacy of radiation therapy by modifying the activity of key cell proliferation and survival pathways such as those controlled by Bcl-2, p53, Akt/PTEN and cyclooxygenase-2. In this article, we summarize the findings of recent investigations of radiosensitizing agents in the treatment of prostate cancer.

Cardiovascular complications of cancer therapy: incidence, pathogenesis, diagnosis, and management

Cancer treatment today employs a combination of chemotherapy, radiotherapy, and surgery to prolong life and provide cure. However, many of these treatments can cause cardiovascular complications such as heart failure, myocardial ischemia/infarction, hypertension, thromboembolism, and arrhythmias. In this article we review the incidence of cardiotoxicity caused by commonly used chemotherapeutic agents as well as discuss the pathogenesis, diagnosis, management, and prevention of these cardiovascular side effects. Cardiotoxicity related to anticancer treatment is important to recognize as it may have a significant impact on the overall prognosis and survival of cancer patients, and it is likely to remain a significant challenge for both cardiologists and oncologists in the future due to an increasing aging population of patients with cancer and the introduction of many new cancer therapies.

Clinical implications of hypoxia inducible factor in renal cell carcinoma

Management of renal cell carcinoma (RCC) has made considerable strides in the past decade, due in large part to identification of the von Hippel Lindau (VHL) tumor suppressor as a negative regulator of hypoxia inducible factor alpha (HIF-alpha) protein expression. Stabilization of HIF-alpha appears to be critical for renal tumorigenesis, and is observed even in VHL-independent RCC. Thus, an understanding of the pathways that regulate expression and activation of the different HIF-alpha isoforms is key to delineating the mechanism of renal transformation and for the development of novel therapeutics. A number of agents targeting HIF-alpha or its transcriptionally-regulated genes have shown promise in treatment of RCC. However, more effective treatment strategies are still needed. This report provides a directed review of recent discoveries defining the role of HIF in renal tumorigenesis and their relevance to the clinical advances in targeted therapy for advanced RCC.