Wirksamkeit von Multikinaseinhibitoren in der Therapie des fortgeschrittenen Nierenzellkarzinoms

Due to the chemoresistance of renal cell cancer, cytokine-based therapeutic approaches were considered the standard treatment for patients with metastatic disease. At present, data that are available from a few phase II/III studies, dealing both with the first- and second-line treatment of patients suffering from systemic progression of RCC, indicate the significantly higher clinical efficacy of multikinase inhibitors when compared with cytokine-based therapeutic regimens. In this context, sorafenib (Nexavar, BAY 43-9006) and sunitinib (Sutent, SU 011248) are the most frequently applied and most intensively investigated substances. In Germany, with regard to a phase III study reported at the ASCO congress in 2006, sunitinib received approval for the first-line therapy of metastatic RCC. The application of multikinase inhibitors follows the principle of targeting such mediators that are considered to be substantially involved in the pathogenesis and particularly progression of renal cell cancer within relatively well-defined molecular pathways. The aim of the present paper is to address and to critically discuss the clinical data that are currently available regarding the therapeutic efficacy of kinase inhibitors during the treatment of metastatic RCC.     

Der Stellenwert der Targeted-Therapie beim Nierenzellkarzinom

Therapeutic approaches based solely on cytokine are meanwhile no longer recommended without restrictions as the primary therapy for metastatic renal cancer due to the reduced clinical response and the promising available data regarding molecular therapy. Several randomized controlled studies have been performed since the introduction of the so-called targeted therapies for metastatic renal cancer. Substantial data relevant for drug approval are available for the multikinase inhibitors sorafenib (Nexavar) and sunitinib (Sutent), the mTOR inhibitor temsirolimus (Torisel), and the monoclonal antibody bevacizumab (Avastin) in combination with interferon-alpha. Sunitinib, temsirolimus, and bevacizumab are approved for first-line treatment, whereas sorafenib was approved for second-line treatment in Germany.Clinical trials are currently investigating the questions of optimal timing, value of neoadjuvant or adjuvant treatment, form, and sequence of the molecular targeted therapy. Experimental investigations for a better understanding of signaling pathways will preferably allow preselecting patients for an individualized therapy in metastatic renal cell cancer (RCC). The aim of the present paper is to address and to critically discuss the clinical data that are currently available regarding"targeted" therapeutics during the treatment of metastatic RCC.     

An update on the medical therapy of advanced metastatic renal cell carcinoma

The effectiveness of multikinase inhibitors in first- and second-line therapy of metastatic renal cell carcinoma (RCC) has been evaluated in various clinical studies. Initial results indicate an increased response rate and a prolonged progression-free survival compared with cytokine-containing therapeutic approaches. The new multitargeted kinase inhibitors sorafenib (Nexavar/BAY 43-9006) and sunitinib (Sutent/SUO 11248) interfere mainly with vascular endothelial growth factor and platelet-derived growth factor pathways. Recently, temsirolimus, a specific inhibitor of mammalian target of rapamycin, demonstrated activity in RCC patients with poor prognosis. This review discusses the effectiveness of the most frequently used substances for systemically progressive RCC in consideration of the currently available clinical data.     

An adult Xp11.2 translocation renal carcinoma showing response to treatment with sunitinib

A rare variant of renal cell carcinoma (RCC) with a translocation involving Xp11.2 has become increasingly recognized as a separate entity in the 2004 World Health Organization (WHO) kidney carcinoma classification. These tumors predominantly affect children and young adults and tend to present with advanced stage disease. Although reported to be indolent in children, adult cases run a more aggressive course. Little is known about their natural history, prognosis and response to therapy.We report a case of Xp11 translocation renal cancer in a 33-year-old male patient who presented with widespread rapidly progressive metastatic disease involving extensive intra-thoracic lymph nodes, supra-clavicular, retroperitoneal lymph nodes, lung nodules, and peritoneal mass.He had failed to respond to treatment with high dose interleukin 2, but showed a significant clinical response to treatment with the multikinase inhibitor sunitinib. CT scan performed after 3 cycles (18 weeks) of therapy revealed more than 65% reduction of measurable disease by response evaluation criteria in solid tumors (RECIST) criteria, resolution of other assessable lesions, and a clinical benefit that lasted for over 13 months. But unfortunately, this was subsequently followed by a rapidly progressive course.The well-recognized clinical efficacy of multikinase inhibitors such as sunitinib and sorafenib is based on the outcomes in patients with clear cell histology. There is limited data on efficacy in non-clear cell RCC, but activity in translocation RCC has not been reported. To our knowledge, this is the first documented case of Xp11 translocation carcinoma to have demonstrated an objective durable response to sunitinib. It remains unclear how resistance to sunitinib develops, but the results to date support further evaluation of sunitinib in cases of translocation RCC.     

Current status of targeted therapy for advanced renal cell carcinoma

The treatment of metastatic renal cell carcinoma (mRCC) has recently evolved from being predominantly cytokine-based treatment to the use of targeted agents, which include sorafenib, sunitinib, bevacizumab (plus interferon alpha [IFN-α]), temsirolimus, everolimus, pazopanib, and most recently, axitinib. Improved understanding of the molecular pathways implicated in the pathogenesis of RCC has led to the development of specific targeted therapies for treating the disease. In Korea, it has been 5 years since targeted therapy became available for mRCC. Thus, we now have broader and better therapeutic options at hand, leading to a significantly improved prognosis for patients with mRCC. However, the treatment of mRCC remains a challenge and a major health problem. Many questions remain on the efficacy of combination treatments and on the best methods for achieving complete remission. Additional studies are needed to optimize the use of these agents by identifying those patients who would most benefit and by elucidating the best means of delivering these agents, either in combination or as sequential single agents. Furthermore, numerous ongoing research activities aim at improving the benefits of the new compounds in the metastatic situation or their application in the early phase of the disease. This review introduces what is currently known regarding the fundamental biology that underlies clear cell RCC, summarizes the clinical evidence supporting the benefits of targeted agents in mRCC treatment, discusses survival endpoints used in pivotal clinical trials, and outlines future research directions.     

Treatment of metastatic renal cell carcinoma and renal pelvic cancer

A better understanding of the molecular biology of renal cell carcinoma (RCC) and the emergence of molecular targeted drugs have revolutionized the treatment for patients with metastatic RCC (mRCC). Multi-targeted tyrosine kinase inhibitors (sorafenib and sunitinib) and mammalian target of rapamycin inhibitors (temsirolimus and everolimus) have recently shown superiority over interferon-α or placebo. However, while the molecular targeted drugs have demonstrated encouraging results, these drugs have also sometimes induced unexpected adverse events. Control of adverse events is important to obtain the maximum effectiveness and sustain quality of life for patients. Because renal pelvic cancer has many similarities in pathogenesis with urinary bladder cancer, the same chemotherapeutic regimen is often proposed for patients with metastatic renal pelvic cancer. Combined chemotherapy with gemcitabine and cisplatin is now widely considered to be first-line chemotherapy against these metastatic diseases; however, there are still unresolved problems with this treatment, including the limited survival benefit. To select new therapeutic modalities, a more profound understanding of the molecular biology of renal pelvic cancer is crucial. The purpose of this review is to summarize the current evidence supporting the role and activities of new chemotherapeutic agents and to reveal potential future directions in the management of mRCC and renal pelvic cancer.     

Updated European Association of Urology Guidelines: Recommendations for the Treatment of First-line Metastatic Clear Cell Renal Cancer

The randomised phase III clinical trial Checkmate-214 showed a survival superiority for the combination of ipilimumab and nivolumab when compared with the previous standard of care in first-line metastatic/advanced clear cell renal cell carcinoma (RCC) (Escudier B, Tannir NM, McDermott DF, et al. CheckMate 214: efficacy and safety of nivolumab plus ipilimumab vs sunitinib for treatment-naïve advanced or metastatic renal cell carcinoma, including IMDC risk and PD-L1 expression subgroups. LBA5, ESMO 2017, 2017). These results change the frontline standard of care for this disease and have implications for the selection of subsequent therapies. For this reason the European Association of Urology RCC guidelines have been updated.

Aktuelles zur Systemtherapie des metastasierten Nierenzellkarzinoms

The past 5 years were marked by fundamental changes in the systemic therapy of metastatic renal cell carcinoma. Up to the end of the last decade cytokine-based chemotherapy was the only, even if only moderately effective systemic therapy for metastatic renal cell carcinoma. Currently there are five new approved drug releases of so-called targeted substances, which function on a molecular based therapeutic mechanism. Sunitinib (Sutent®) and sorafenib (Nexavar®) as multikinase inhibitors, everolimus (Afinitor®) and temsirolimus (Torisel®) as mTOR inhibitors, and bevacizumab as an antibody against VEGF in combination with interferon-alpha (IFN-α). The following article will give an overview of the currently available substances and critically discuss therapy plans and future trends.     

Metastatic non-clear cell renal cell carcinoma: current therapeutic options

Non-clear cell (ncc) renal cell carcinoma (RCC) accounts for approximately 25% of all patients with metastatic RCC. It is refractory to standard immuno(chemo)therapy and, to date, no specific trials have been reported to evaluate the efficacy of novel targeted drugs in the different subtypes of metastatic nccRCC. We review all available data from subgroup analyses of the global sorafenib and sunitinib expanded access programmes, current phase-III trials, and smaller multi- and single-centre studies focusing on the activity of targeted agents in these specific and rare RCC subtypes. Both sorafenib and sunitinib have significant activity in metastatic nccRCC, but the efficacy of each agent seems to vary between different nccRCC forms. Preliminary clinical data for temsirolimus appear to be promising but more extensive and long-term data are awaited. With the advent of novel therapeutic options, specific controlled multicentre trials are urgently needed to define their exact value and efficacy for treating the historically resistant nccRCC forms. The medium-term aim should be to tailor the most advantageous therapy for each patient with respect to his/her individual RCC subtype and physical condition.     

Current Treatment in Advanced Renal Cell Carcinoma (RCC): Impact of Targeted Therapies in the Management of RCC

Renal cell carcinoma (RCC) is a highly resistant tumour for which there are currently no therapies that are effective across all patient subgroups. Recently, there has been an increased understanding of the molecular pathophysiology underlying RCC. The von Hippel–Lindau/hypoxia–inducible factor pathway has been strongly implicated in RCC. Several key molecules of this signalling pathway, including vascular endothelial growth factor, platelet-derived growth factor, epidermal growth factor, and the mammalian target of rapamycin have been identified. The recognition that these molecules play a pivotal role in tumour angiogenesis and tumour cell proliferation has led to the development of novel targeted agents for therapeutic intervention. This article discusses the efficacy of standard treatments for RCC and describes targeted agents that are currently being evaluated in clinical trials. Whilst the results from trials of epidermal growth factor receptor inhibitors have generally been disappointing, bevacizumab, sorafenib, sunitinib, and temsirolimus have shown potential in clinical trials. To date, both sorafenib and sunitinib are well tolerated and have demonstrated activity in phase 3 trials in patients with advanced or metastatic RCC, whilst temsirolimus has shown activity in a subgroup of poor-prognosis patients with advanced RCC.     

Clinical efficacy and prognostic factors for overall survival in Japanese patients with metastatic renal cell cancer treated with sunitinib

Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? A randomized prospective phase III clinical trial for systemic treatment‐naïve metastatic renal cell cancer (RCC) patients demonstrated the superiority of sunitinib over interferon with an acceptable safety profile. However, a commonly asked question is whether patients with RCC in clinical trials are representative of those with this disease being seen in ordinary clinical practice. To our knowledge, this is the first report of sunitinib for the Japanese patients with metastatic RCC in ordinary clinical practice. The estimated median PFS and OS in this study were 9.3 and 32.2 months, respectively. The application of the MSKCC model distinctly separated OS curves (P < 0.001), suggesting that MSKCC prognostic factors might be still valid to predict survival in metastatic RCC in the era of molecular targeted therapy.

OBJECTIVES

• ? To report the treatment efficacy and safety profile of sunitinib for patients with metastatic renal cell carcinoma (RCC) in ordinary clinical practice.
• ? In addition, to investigate the prognostic clinicopathological factors in these patients.

PATIENTS AND METHODS

• ? The present study consisted of native Japanese patients with metastatic RCC, comprising 29 pretreated and 34 systemic treatment‐naïve patients.
• ? Univariate and multivariate analyses were performed by the log‐rank test and the Cox proportional hazards model, respectively.

RESULTS

• ? Estimated median progression‐free survival and overall survival (OS) were 9.3 months (95% confidence interval, CI, 5.0–13.7) and 32.2 months (95% CI, 24.4–40.0), respectively.
• ? Among the patients pretreated before sunitinib, two patients were treated with initialized systemic therapy with sorafenib and the remaining 27 were initialized with interferon‐α.
• ? The OS from the initial systemic therapy of the patients in pretreated groups was 79.6 months (95% CI, 14.6–144.5).
• ? The application of the Memorial Sloan‐Kettering Cancer Center model distinctly separated the OS curves (P < 0.001).
• ? The most common grade 3 adverse events were fatigue (53%), thrombocytopaenia (48%), hand‐foot syndrome (16%), anaemia (20%), hypertension (10%) and leucopaenia (9%), although these events were manageable and reversible.

CONCLUSIONS

• ? Sunitinib has a favourable efficacy/safety profile for Japanese metastatic RCC patients in clinical practice.
• ? The estimated median OS was >2 years with acceptable tolerability.
• ? The median OS from the initial systemic therapy of the pretreated patients was >6 years.
• ? Memorial Sloan‐Kettering Cancer Center prognostic factors still appear to be valid for predicting survival in metastatic RCC in the era of molecular targeted therapy.

     

Systemische und operative Therapie des metastasierten Nierenzellkarzinoms

Several targeted therapies have become available for first-line (sunitinib, bevacizumab, pazopanib, temsirolimus) and second-line (sorafenib, pazopanib, everolimus) use in recent years. The superior outcomes achieved with these targeted agents have led to replacement of the formerly administered cytokines. New developments have raised the question of whether patients benefit from sequential therapies with tyrosine kinase inhibitors and/or whether combination regimes can improve clinical outcomes. This review gives an overview of the current therapeutic options for first- and second-line treatment in metastatic RCC as well as sequential and combination therapies. Adjuvant and neoadjuvant treatment options are being discussed. Furthermore, this review addresses surgical alternatives in the treatment of RCC.     

Novel approaches in the therapy of metastatic renal cell carcinoma

Renal cell carcinoma (RCC) is the most lethal of the common urologic malignancies, with approximately 40% of patients eventually dying of cancer progression. Approximately one third of patients present with metastatic disease, and up to 40% treated for localized disease have a recurrence. Recent advances in the understanding of the pathogenesis, behavior, and molecular biology of RCC have paved the way for developments that may enhance early diagnosis, better predict tumor prognosis, and improve survival for RCC patients. The recent discovery of molecular tumor markers is expected to revolutionize the staging of RCC in the future and lead to the development of new therapies based on molecular targeting. Cytokine-based immunotherapy can be considered standard therapy in the treatment of metastatic RCC today. However, new therapies such as tumor vaccines, anti-angiogenesis agents, and small molecule inhibitors are being developed to improve efficacy and treat those patients who are unable to tolerate or are resistant to systemic immunotherapy. The aim of this review is to provide an update on current therapeutic approaches and targeted molecular therapy for metastatic RCC.     

Current status in molecular-targeted therapy and IFNα for renal cell carcinoma in Japan

It has been two years since molecular-targeted therapy became available for advanced renal cell carcinoma (RCC) in Japan. It shall be validated whether molecular-targeted therapy really improved the prognosis of patients with advanced RCC in the near future. Here we review the two phase III clinical studies that demonstrated the superiority of sunitinib and temsirolimus over IFNα and discuss optimal therapy including IFNα for advanced RCC in the future biomarker era.     

Sunitinib efficacy against advanced renal cell carcinoma

PURPOSE: We assessed the efficacy of the oral multitargeted tyrosine kinase inhibitor sunitinib in patients with metastatic clear cell renal cell carcinoma. MATERIALS AND METHODS: Patients with metastatic clear cell renal cell carcinoma were enrolled in this multicenter, phase II clinical trial. Major eligibility requirements were clear cell renal cell carcinoma histology, prior nephrectomy, measurable metastases and failed prior cytokine therapy as a result of disease progression. Sunitinib was given orally as second line therapy in 6-week cycles of 50 mg daily for 4 weeks, followed by 2 weeks off drug per treatment cycle. Response to sunitinib was rigorously assessed by an independent third party core imaging laboratory (central review). RESULTS: Of 106 patients enrolled in the study 105 were evaluated for response. As determined by independent third party assessment, the objective response rate was 33% (95% CI 24%-43%) with a median response duration of 14.0 months. Median time to progression and median progression-free survival in the 105 evaluable patients was 10.7 and 8.8 months, respectively. Median survival was 23.9 months and 43 patients remained alive at a median followup of 29.7 months. CONCLUSIONS: The results of this trial demonstrate the efficacy of sunitinib for metastatic renal cell carcinoma. The optimal integration of surgery and sunitinib treatment requires further prospective investigation.     

Current management and future perspectives of metastatic renal cell carcinoma

Over the last number of years, the treatment of metastatic renal cell cancer has evolved tremendously with the advent of targeted therapy. Previously, immunotherapies, such as interferon alpha and interleukin‐2, were the only treatment options available for this chemoresistant malignancy. Currently, seven additional agents, including sunitinib, sorafenib, axitinib, pazopanib, bevacizumab, everolimus and temsirolimus, have been approved for use in metastatic renal cell cancer, with several more in development. The efficacy of these agents depends primarily on inhibition of the vascular endothelial growth factor and mammalian target of rapamycin pathways, and have drastically improved the outcomes of patients diagnosed with metastatic renal cell cancer. This article reviews the major treatment advances that have occurred for metastatic renal cell cancer with the advent of targeted treatments, summarizes the evidence to support their use and addresses clinical issues that have arisen with them. To help guide clinicians in their decision‐making with these emerging therapeutic choices, the evidence for sequencing and combining these agents, and the need for biomarkers will be addressed. The role of surgical management options, such as cytoreductive nephrectomy and metastectomy, in the era of targeted treatment is also reviewed. Several novel treatments are also on the horizon, which might serve as future avenues for treatment advancement in metastatic renal cell cancer.     

Use of tyrosine kinase inhibitors in patients with metastatic kidney cancer receiving haemodialysis: a retrospective Italian survey

Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Sunitinib and sorafenib are orally administered multikinase inhibitors approved for the treatment of advanced RCC. The limited pharmacokinetics data on sunitinib and sorafenib suggest that haemodialysis does not significantly alter plasma concentrations. In this retrospective study we define the safety and efficacy of tyrosine kinase inhibitors in patients with metastatic RCC (mRCC) and end‐stage renal disease requiring haemodialysis. Even though the retrospective nature of this survey and the relatively small sample size represent major limitations, these data indicate that treatment with sunitinib and sorafenib in this cohort of patients is feasible with no unexpected toxicity and good efficacy, results similar to those in the general population of patients with mRCC.

OBJECTIVE

• ? To investigate the safety and efficacy of tyrosine kinase inhibitors (TKIs) in patients with metastatic renal cell carcinoma (mRCC) and end‐stage renal disease requiring haemodialysis (HD).

PATIENTS AND METHODS

• ? Between July 2006 and December 2010, 24 patients undergoing HD were treated with sunitinib and/or sorafenib for mRCC in 14 Italian institutions.
• ? We retrospectively reviewed the medical records of these patients to evaluate the administered doses of TKIs, treatment‐related toxicities and the clinical response to therapy.

RESULTS

• ? Sunitinib was administered at 50 mg daily for 4–6 weeks in six patients, 37.5 mg daily for 4–6 weeks in seven patients (one patient subsequently increased the dose to 50 mg daily), 25 mg daily for 4–6 weeks in two patients and 12.5 mg daily for 4–6 weeks in one patient. Among the eight patients treated with sorafenib, four patients received 800 mg daily (400 mg every 12 h), three patients 400 mg daily and one patient 200 mg daily with a continuous schedule.
• ? The estimated median progression‐free and overall survival periods of this cohort of patients were 10.3 months and 22.6 months, respectively.
• ? With regard to tolerability and safety, no unexpected adverse events were registered and no grade 4 haematological or non‐haematological toxicities were reported.

CONCLUSIONS

• ? Sunitinib and sorafenib treatment is not contraindicated in patients with mRCC undergoing HD.
• ? The outcome of this patient population is similar to that observed in patients with normal renal function treated with TKIs.
• ? These results merit further confirmation by a larger prospective trial.

     

Treatment of Advanced and Metastatic Renal Cancer: A Revolution?

ContextA significant proportion of patients with renal cell carcinoma (RCC) will experience recurrence or tumour progression after surgical treatment. Nowadays, several treatment options, including immunotherapy and targeted therapies, are available for management of advanced and metastatic RCC.ObjectiveThis paper aims to give an overview of the current treatment options for patients with advanced and metastatic RCC.Evidence acquisitionThis paper is based on a presentation given at the 6th Meeting of the European Society of Oncological Urology 2009, held in Istanbul, Turkey. Data were retrieved from recent review articles, original articles, and abstracts on the treatment of advanced and metastatic RCC.Evidence synthesisThe potential role of adjuvant vaccines in treatment of patients with advanced RCC after nephrectomy has been suggested. With regard to the newly developed targeted agents for treatment of metastatic clear-cell RCC, sunitinib and bevacizumab plus interferon-α (INF-α) seem promising as first-line therapy for good- and intermediate-risk patients. Temsirolimus appears to be effective as first-line treatment in metastatic RCC (mRCC) patients with poor prognosis. Sorafenib and everolimus should be considered as second-line therapy in mRCC patients. Some targeted therapies have also demonstrated clinical activities in patients with metastatic non–clear-cell RCC. Although grade 1 and grade 2 treatment-related adverse events were common with targeted therapies, most were manageable. The effect of targeted agents in earlier stage disease is currently under investigation. Cytokine therapy was associated with a modest survival benefit in mRCC. A combined analysis, however, suggested that cytoreductive nephrectomy might improve survival in patients with mRCC treated with interferon immunotherapy.ConclusionsMore research on the use of adjuvant vaccines in treating patients with advanced RCC is warranted. Although the management of metastatic disease has undergone a revolution in recent years, a lot of questions still need to be answered.     

Continued Progress in the Treatment of Advanced Renal Cell Carcinoma: An Update on the Role of Sunitinib

ContextRenal cell carcinoma (RCC) constitutes approximately 2–3% of all cancers worldwide. Approximately a third of patients diagnosed with RCC present with metastatic disease (mRCC) and in about a third of patients with localized disease, RCC recurs following treatment. Metastatic renal cell carcinoma (mRCC) is associated with poor survival rates, and until recently, cytokines were the only treatment options for mRCC.ObjectiveThe rationale for the use of targeted agents in mRCC is reviewed, and the key challenges to optimizing treatment are discussed.Evidence acquisitionClinical data on the safety and efficacy of targeted agents in mRCC, practical therapy management, and patient stratification strategies are reviewed.Evidence synthesisThe development of targeted agents, including sunitinib, sorafenib, temsirolimus, and bevacizumab (given with interferon-α [IFN-α]) has dramatically changed the outlook for patients with mRCC and improved survival rates. Sunitinib has demonstrated clinical efficacy for mRCC in phase 2 and phase 3 trials and in an expanded-access study. Sunitinib is now a reference standard of care for the first-line treatment of patients with mRCC.As with the other targeted agents, sunitinib treatment is associated with a particular profile of adverse events (AE). Management of AEs is critical, as tolerability can affect adherence to therapy and limit clinical benefit. The development of practical strategies to support the optimal use of targeted agents is essential.In addition, prognostic factors such as tumor histology affect treatment outcome. Patient stratification into risk groups based on prognostic factors allows optimal treatment selection. A treatment algorithm, based on patient stratification and the available clinical data for the targeted agents, may facilitate the optimal choice of treatment for patients with mRCC.ConclusionsThis supplement reviews the clinical data from sunitinib studies in mRCC as well as practical therapy-management strategies and presents a treatment algorithm for mRCC. Finally, experience from the clinic is presented.     

High frequency of intracerebral hemorrhage in metastatic renal carcinoma patients with brain metastases treated with tyrosine kinase inhibitors targeting the vascular endothelial growth factor receptor

OBJECTIVES: To report the high incidence of intracerebral hemorrhage (ICH) in patients with metastatic renal cell carcinoma (RCC) treated with the tyrosine kinase inhibitors targeting the vascular endothelial growth factor receptor (VEGFR). METHODS AND RESULTS: Between October 2005 and December 2006, 67 patients with metastatic RCC were treated with sorafenib or sunitinib at the Montpellier Cancer Center in compassionate access programs. The medical records of five (7%) patients who died of ICH during therapy were reviewed retrospectively. Four of them had known brain metastases. Previous radiation therapy had been indicated in two patients. Two patients had a history of hypertension. Death from ICH occurred in the first 2 wk following the onset of treatment. Three other patients with brain metastases who received sorafenib or sunitinib during the same period did not experience ICH. CONCLUSIONS: The frequency of fatal ICH in RCC patients with brain metastases treated with tyrosine kinase inhibitors targeting the VEGFR seems high. Prospective clinical trials will be necessary for assessing the true incidence and predictive factors related to this toxicity.