Blue Dye Embolization of Renal Tumor: A New Technique to Improve Tumor Localization During Laparoscopic Partial Nephrectomy.

Purpose: To improve the tumor localization during laparoscopic surgery, we describe an innovative technique involving superselective intra-arterial injection of blue dye in tumoral vessels to color the tumor before surgical enucleation. Materials and Methods: The dye injection was performed at the same time as superselective embolization, immediately before laparoscopic surgery in a hybrid operating room. We used this new treatment sequence on 50 consecutive patients. Results: The selective intra-arterial injection of an emulsion of blue dye and lipiodol was feasible in 46 (92%) cases and well tolerated, followed by superselective embolization of the tumor vessels with glue or coils. The tumor was easily localized during surgery due to the blue coloration. Tumor coloration was not associated with postoperative complication, especially allergic reaction or renal failure. Pathologic analysis of the tumor was not modified by the coloration and all tumors had negative surgical margins. Conclusions: The preoperative dye localization is a feasible, safe, and accurate procedure. This combined approach reduces the difficulty of surgery and increases patient safety.

Preclinical impact of high dose intermittent antiangiogenic tyrosine kinase inhibitor pazopanib in intrinsically resistant tumor models.

Antiangiogenic tyrosine kinase inhibitors (TKIs) target vascular endothelial growth factor receptors and other receptor tyrosine kinases. As a result of toxicity, the clinical failures or the modest benefits associated with antiangiogenic TKI therapy may be related in some cases to suboptimal drug dosing and scheduling, thereby facilitating resistance. Most antiangiogenic TKIs, including pazopanib, are administered on a continuous daily basis. Here, instead, we evaluated the impact of increasing the dose and administering the drug intermittently. The rationale is that using such protocols, antitumor efficacy could be enhanced by direct tumor cell targeting effects in addition to inhibiting tumor angiogenesis. To test this, we employed two human tumor xenograft models, both of which manifest intrinsic resistance to pazopanib when it is administered continuously: the VHL-wildtype SN12-PM6-1 renal cell carcinoma (RCC) and the metastatic MDA-MB-231/LM2-4 variant breast cancer cell line, when treated as distant metastases. We evaluated four different doses and schedules of pazopanib in the context of primary tumors and advanced metastatic disease, in both models. The RCC model was not converted to drug sensitivity using the intermittent protocol. Using these protocols did not enhance the efficacy when treating primary LM2-4 tumors. However, one of the high-dose intermittent pazopanib protocols increased median survival when treating advanced metastatic disease. In conclusion, these results overall suggest that primary tumors showing sensitivity to continuous pazopanib treatment may predict response to this drug when given at high doses intermittently in the context of advanced metastatic disease, that are otherwise resistant to the conventional protocol.

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

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

A Decade of Experience in Developing Preclinical Models of Advanced- or Early-Stage Spontaneous Metastasis to Study Antiangiogenic Drugs, Metronomic Chemotherapy, and the Tumor Microenvironment.

The clinical circumstance of treating spontaneous metastatic disease, after resection of primary tumors, whether advanced/overt or microscopic in nature, is seldom modeled in mice and may be a major factor in explaining the frequent discordance between preclinical and clinical therapeutic outcomes where the trend is "overprediction" of positive results in preclinical mouse model studies. To evaluate this hypothesis, a research program was initiated a decade ago to develop multiple models of metastasis in mice, using variants of human tumor cell lines selected in vivo for enhanced spontaneous metastatic aggressiveness after surgical resection of established orthotopic primary tumors. These models have included breast, renal, and colorectal carcinomas; ovarian cancer (but without prior surgery); and malignant melanoma. They have been used primarily for experimental therapeutic investigations involving various antiangiogenic drugs alone or with chemotherapy, especially "metronomic" low-dose chemotherapy. The various translational studies undertaken have revealed a number of clinically relevant findings. These include the following: (i) the potential of metronomic chemotherapy, especially when combined with a vascular endothelial growth factor pathway targeting drug to successfully treat advanced metastatic disease; (ii) the development of relapsed spontaneous brain metastases in mice with melanoma or breast cancer whose systemic metastatic disease is successfully controlled for a period with a given therapy; (iii) foreshadowing the failure of adjuvant antiangiogenic drug-based phase III trials; (iv) recapitulating the failure of oral antiangiogenic tyrosine kinase inhibitors plus standard chemotherapy in contrast to the modest successes of antiangiogenic antibodies plus chemotherapy in metastatic breast cancer; and (v) revealing "vessel co-option" and absence of angiogenesis as a determinant of intrinsic resistance or minimal responsiveness to antiangiogenic therapy in lung metastases. Developing similar models of metastatic disease but involving mouse tumors grown in syngeneic immunocompetent mice may also prove useful for future translational studies of immune therapy-based treatments.

Treatment of collecting duct carcinoma: current status and future perspectives.

BACKGROUND: Chemotherapy for collecting duct carcinoma (CDC) has demonstrated only limited efficacy in the advanced setting. The present study evaluated the activity of targeted therapies in metastatic CDC. PATIENTS AND METHODS: We evaluated a cohort of 384 consecutive patients with metastatic renal cell carcinoma (mRCC). The characteristics of patients with CDC were compared against those of the remaining cohort. All patients with CDC were treated with targeted therapies. RESULTS: Thirteen patients with advanced CDC were referred to our Center (incidence: 3.4% of all mRCC). Median age was 57 and 62 years in the CDC and non-CDC groups, respectively. The overall disease control in the CDC population was 23%, and median overall survival was 4 (95% confidence interval(CI)=2.4-5.6) months. Three patients obtained a satisfying response (disease control lasting 6-33 months). CONCLUSION: CDC has a poor prognosis compared to non-CDC renal cell carcinoma. Treatment for CDC represents a future challenge and targeted therapies may play a role in selected cases.

Tyrosine kinase inhibitor-induced vasculopathy in clear cell renal cell carcinoma: an unrecognized antitumour mechanism.

AIMS: To evaluate the pathological features of clear cell renal cell carcinoma (CCRCC) treated with tyrosine kinase inhibitors (TKIs), and to elucidate the mechanism of action of TKIs. METHODS AND RESULTS: Twenty cases of CCRCC treated with TKIs (sorafenib or sunitinib) were retrospectively analysed: 16 were patients who had undergone radical nephrectomy after neoadjuvant TKI therapy, and four were autopsy cases of patients who received TKI treatment. All tumours had two distinct regions: one characterized by necrosis and/or degeneration, indicating antitumour activity; and the other characterized by no or few pathological changes, indicating the absence of antitumour activity. Vasculopathy of tumour vessels was observed in or adjacent to the necrotic or degenerative areas; a decreased density of endothelial cells was noted in the tumour vessels. Few or no changes of vasculopathy were observed in tumour vessels in the other CCRCC areas, indicating the absence or low levels of antitumour activity. CONCLUSIONS: This is the first pathological report of vasculopathy in TKI-treated CCRCC cases. Our data suggest that TKIs initially induce vasculopathy in tumour vessels, and consequently cause reduction or diminution of blood supply to the CCRCCs, resulting in antitumour activity characterized by necrosis and hyalinization.

Angiogenic and signalling proteins correlate with sensitivity to sequential treatment in renal cell cancer.

BACKGROUND: We aimed to study key signalling proteins involved in angiogenesis and proliferation on the response to inhibitors of tyrosine kinases and mammalian target of rapamycin in first- and in second-line treatment of renal cell carcinoma (RCC). METHODS: In a panel of human RCC tumours, in vitro and in nude mice, we evaluated the effect of sunitinib, sorafenib and everolimus, alone and in sequence, on tumour growth and expression of signalling proteins involved in proliferation and resistance to treatment. RESULTS: We demonstrated that, as single agents, sunitinib, sorafenib and everolimus share similar activity in inhibiting cell proliferation, signal transduction and vascular endothelial growth factor (VEGF) secretion in different RCC models, both in vitro and in tumour xenografts. Pre-treatment with sunitinib reduced the response to subsequent sunitinib and sorafenib but not to everolimus. Inability by sunitinib to persistently inhibit HIF-1, VEGF and pMAPK anticipated treatment resistance in xenografted tumours. After first-line sunitinib, second-line treatment with everolimus was more effective than either sorafenib or rechallenge with sunitinib in interfering with signalling proteins, VEGF and interleukin-8, translating into a significant advantage in tumour growth inhibition and mice survival. CONCLUSION: We demonstrated that a panel of angiogenic and signalling proteins can correlate with the onset of resistance to sunitinib and the activity of everolimus in second line.

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

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

Tyrosine kinase inhibitors for metastatic renal cell carcinoma.

Renal cell carcinoma accounts for 2-3% of all adult malignancies worldwide, and around 30% of patients with the condition present with advanced or metastatic disease.1,2 Until recently, cytokine therapy (e.g. interleukin-2 or interferon-alfa) was the standard treatment for metastatic renal cell carcinoma but provided only a small survival advantage (e.g. extending life by a median of 2.5 months).3 A key development has been the introduction of drugs known as receptor tyrosine kinase inhibitors, which include ▾sunitinib (Sutent-Pfizer), ▾sorafenib (Nexavar-Bayer) and ▾pazopanib (Votrient-GlaxoSmithKline). Here we review the evidence on the efficacy, tolerability and cost-effectiveness of these treatments in renal cell carcinoma.

[Novelties in the treatment for advanced renal-cell cancer]. / Új lehetoségek a vesedaganatok onkológiai kezelésében.

Therapeutic options in advanced renal-cell cancer have expanded through better understanding of molecular pathology and development of novel targeted therapeutics. Vascular endothelial growth factor, the key ligand of angiogenesis, has a major role in the progression of vascularized kidney tumors and this is the target molecule of modern medications. The three types of the mechanism of action of current therapies are: monoclonal antibodies blocking directly vascular endothelial growth factor ligand (bevacizumab), tyrosine-kinase inhibitors blocking vascular endothelial growth factor receptors (sorafenib, sunitinib, pazopanib) and inhibitors of the intracellular mTOR-kinase (temsirolimus, everolimus). Based on randomized studies, sunitinib, pazopanib or interferon-α-bevacizumab combination should be the first-line therapy in patients with good/moderate prognosis, while temsirolimus is recommended in those with poor prognosis. Following an ineffective cytokine therapy sorafenib or pazopanib are the second-line treatment. In case of tyrosine-kinase inhibitor inefficacy, current evidence favors everolimus. Patient outcome can further be improved by the involvement of more modern and effective target products.

Inhibition of angiogenic and non-angiogenic targets by sorafenib in renal cell carcinoma (RCC) in a RCC xenograft model.

BACKGROUND: It is widely recognised that sorafenib inhibits a range of molecular targets in renal cell carcinoma (RCC). In this study, we aim to use patient-derived RCC xenografts to delineate the angiogenic and non-angiogenic molecular targets of sorafenib therapy for advanced RCC (aRCC). METHODS: We successfully generated three patient RCC-derived xenografts in severe combined immunodeficient mice, consisting of three different RCC histological subtypes: conventional clear cell, poorly differentiated clear cell RCC with sarcomatoid changes, and papillary RCC. This study also used clear cell RCC cells (786-0/EV) harbouring mutant VHL to investigate the clonogenic survival of cells transfected with survivin sense and antisense oligonucleotides. RESULTS: All three xenografts retain their original histological characteristics. We reported that sorafenib inhibited all three RCC xenograft lines regardless of histological subtypes in a dose-dependant manner. Sorafenib-induced growth suppression was associated with not only inhibition of angiogenic targets p-PDGFR-ß, p-VEGFR-2, and their downstream signalling pathways p-Akt and p-ERK, cell cycle, and anti-apoptotic proteins that include cyclin D1, cyclin B1, and survivin but also upregulation of proapoptotic Bim. Survivin knockdown by survivin-specific antisense-oligonucleotides inhibited colony formation and induced cell death in clear cell RCC cells. CONCLUSION: This study has shed light on the molecular mechanisms of sorafenib in RCC. Inhibition of non-angiogenic molecules by sorafenib could contribute in part to its anti-tumour activities observed in vivo, in addition to its anti-angiogenic effects.

Pure ethiodized oil-based transcatheter ablative therapy in normal rabbit kidneys and kidneys inoculated with VX-2 carcinoma.

PURPOSE: To evaluate the efficacy of ablation with selective arterial injection of pure ethiodized oil followed by arterial occlusion with 9:1 ethanol-Ethiodol mixture (EEM) and coil placement in normal rabbit kidneys and kidneys inoculated with VX-2 carcinoma. MATERIALS AND METHODS: All experiments were conducted with Animal Care and Use Committee approval. In six rabbits (group 1), one kidney was embolized with pure Ethiodol until capillary stasis, followed by injection of 9:1 EEM until arterial stasis and then coil placement into the main renal artery. In 12 other rabbits, one kidney was inoculated with VX-2 tumor. Ethiodol and EEM embolization and coil placement followed 7 days later (group 2, n = 6) or 11-14 days later (group 3, n = 6). Kidneys were evaluated (angiography, computed tomography, macro- and microscopy) 7 days after treatment. RESULTS: Capillary stasis was achieved in groups 1, 2, and 3 with (mean ± standard deviation) 0.47 ± 0.03, 0.53 ± 0.02, and 0.56 ± 0.04 ml of pure Ethiodol, followed by 0.47 ± 0.05, 0.42 ± 0.03, and 0.38 ± 0.04 ml of EEM, respectively, which caused complete arterial occlusion in 17 of 18 kidneys. In group 1, all but one kidney showed at least 95% generalized coagulative necrosis. In group 2, all six kidneys exhibited 100% coagulative necrosis, with no viable tumor present. In group 3, 100% coagulative necrosis was present in all kidneys, with a small viable tumor in one. CONCLUSION: In the rabbit, selective arterial injection of pure Ethiodol can cause complete renal parenchyma and tumor ablation when it is followed by prompt, contiguous, and permanent occlusion of the arterial compartment.

Evolution of renal function in patients treated with antiangiogenics after nephrectomy for renal cell carcinoma.

PURPOSE: Side effects of antiangiogenic agents are moderate compared with other therapies. The most frequent adverse events are of a renovascular origin and manifest as hypertension (HTN) and thrombotic microangiopathy. To date, data are scanty on the renal tolerance of such drugs regarding renal function as itself, i.e., glomerular filtration rate (GFR). We report on the evolution of GFR in patients receiving antiangiogenic therapy after unilateral nephrectomy for kidney cancer. PATIENTS AND METHODS: Data from 73 patients followed in our oncology department for kidney cancer, who had undergone unilateral nephrectomy, and received any antiangiogenic therapy were reviewed. Their GFR was calculated using the aMDRD formula. RESULTS: All patients showed a declining renal function over time (-1.23 and -2.51 mL/min/1.73 m(2) using the slope of the curve or the difference between GFR at baseline and that at the end of treatment, respectively). Among them, patients who were recorded as having HTN before initiation of antiangiogenic therapy showed a higher decrease in their GFR of -13.28 and -12.06 mL/min/1.73 m(2). CONCLUSION: We recommend that blood pressure should be measured closely in those patients before initiation of antiangiogenic therapy. When HTN is diagnosed, it should be treated and renal function should be monitored since those patients may be at risk for rapidly decreasing renal function under therapy.

[Treatment of locally advanced renal tumors]. / Tratamiento de los tumores renales localmente avanzados.

INTRODUCTION: Locally advanced renal tumors show a high progression rate after surgery. Surgical treatment of renal tumors has some unique characteristics related to involvement of the adrenal gland, vena cava, or regional lymph nodes. OBJECTIVE: To review the current treatment of locally advanced renal tumors. MATERIALS AND METHODS: A review is made of both the different drugs used and the different therapeutic possibilities in these tumors. RESULTS: Systemic treatment with angiogenesis inhibitors may improve the natural history of these patients. Systemic treatment may be administered before surgery or as an adjuvant to surgical treatment. Early studies showed a decrease in tumor mass when treatment is administered before surgery, but no prospective randomized studies providing adequate evidence for recommending neoadjuvant treatment are available. CONCLUSIONS: Availability of systemic treatment with angiogenesis inhibitors may open an important field in the treatment of these tumors in both the neoadjuvant setting and as adjuvants to surgery, but no sufficiently solid scientific evidence as to recommend their use is currently available. Randomized studies with sunitinib and sorafenib will probably suggest the adequate approach to be used when their final results are reported.

Thermoablation of malignant kidney tumors using magnetic nanoparticles: an in vivo feasibility study in a rabbit model.

The objective of this study was to assess the technical feasibility of CT-guided magnetic thermoablation for the treatment of malignant kidney tumors in a VX2 tumor rabbit model. VX2 tumors were implanted into the kidneys of five rabbits and allowed to grow for 2 weeks. After preinterventional CT perfusion imaging, CT-guided injection of superparamagnetic iron oxide particles (300 microl) was performed, followed by exposure of the animals to an alternating electromagnetic field for 15 min (approximately 0.32 kA/m). Then animals underwent CT perfusion imaging again. Afterward, animals were sacrificed and kidneys were dissected for macroscopic and histological evaluation. Changes in perfusion before and after exposure to the alternating magnetic field were analyzed. In one animal no tumor growth could be detected so the animal was used for optimization of the ablation procedure including injection technique and peri-interventional cross-sectional imaging (CT, MRI). After image-guided intratumoral injection of ferrofluids, the depiction of nanoparticle distribution by CT correlated well with macroscopic evaluation of the dissected kidneys. MRI was limited due to severe susceptibility artefacts. Postinterventional CT perfusion imaging revealed a perfusion deficiency around the ferrofluid deposits. Histological workup showed different zones of thermal damage adjacent to the ferrofluid deposits. In conclusion, CT-guided magnetic thermoablation of malignant kidney tumors is technically feasible in an animal model and results in a perfusion deficiency indicating tumor necrosis as depicted by CT perfusion imaging and shown in histological evaluation.

Antiangiogenic effect of ZSTK474, a novel phosphatidylinositol 3-kinase inhibitor.

Angiogenesis is known to be required for tumour growth and metastasis. Recent reports indicated that phosphatidylinositol 3-kinase (PI3K) promoted angiogenesis by inducing expressions of HIF-1alpha and vascular endothelial growth factor (VEGF). The present study aims to investigate the antiangiogenic effect of ZSTK474, a novel pan-PI3K inhibitor. ZSTK474 significantly inhibited tumour growth in the RXF-631L xenograft model. Immunohistochemical staining of the tumour tissue with anti-von Willebrand Factor antibody showed a significantly reduced number of microvessels in the ZSTK474-treated mice, suggesting the highly promising antiangiogenic activity in vivo. In human umbilical vein endothelial cells (HUVECs), submicromolar concentrations of ZSTK474 inhibited cell growth, blocked VEGF-induced cell migration and the tube formation, and thus revealed potent in vitro antiangiogenic activity. Furthermore, ZSTK474 inhibited phosphorylation of Akt at submicromolar concentrations. In RXF-631L cancer cells, on the other hand, ZSTK474 treatment inhibited the expression of HIF-1alpha and secretion of VEGF. Together, these results suggest that ZSTK474 has potent antiangiogenic activity, which could be attributed to dual-target inhibitory properties: inhibition of VEGF secretion by cancer cells and inhibition of PI3K in endothelial cells.

[Systemic therapy of metastasizing renal cell carcinoma]. / Systemische Therapie des metastasierten Nierenzellkarzinoms.

Once surgical options have been exhausted, systemic therapy is indicated for metastasizing renal cell carcinoma. Until recently this was carried out using mainly immunotherapeutic concepts with unsatisfactory results. Since the majority of clear cell renal cell carcinomas are well vascularised, angiogenetic inhibition offered an alternative therapy goal. To date, four substances have been approved to control angiogenesis in the therapy of renal cell carcinoma: sunitinib, sorafenib, temsirolimus, as well as a combination of bevacizumab and interferon alpha. Other substances, such as everolimus, pazopanib and axitinib, are currently the subject of clinical trials. Initial data on tolerance and efficacy was presented at this years annual conference of the American Society of Clinical Oncology (ASCO). This article examines current therapy options and ASCO data and discusses future trends.

[Anti-angiogenic treatment in the management of metastatic renal cell carcinoma]. / Les traitements anti-angiogéniques dans la prise en charge du cancer du rein métastatique.

Anti-angiogenic treatments have recently been incorporated as a milestone in the management of metastatic renal cell carcinoma. This retrospective study explores this new practice in 94 patients treated by sorafenib, bevacizumab or sunitinib in the department of oncology of CHU of Bordeaux in a 32 months period. The adverse effects reported are similar than those from prospective trials but for some different in frequency or severity. Efficacy of these drugs appeared more modest than expected from phase III trials. An objective response rate or stabilisation longer than six month was seen in 35% of the patients. Median overall survival was 14.1 months (IC 95%: 8.3-18.7 months). Nevertheless, the population considered in this study had a worse prognosis with more patients with an altered general status (OMS 2 or 3: 13.8%).