First-line therapy for adults with advanced renal cell carcinoma: a systematic review and network meta-analysis

BACKGROUND

Since the approval of tyrosine kinase inhibitors, angiogenesis inhibitors and immune checkpoint inhibitors, the treatment landscape for advanced renal cell carcinoma (RCC) has changed fundamentally. Today, combined therapies from different drug categories have a firm place in a complex first-line therapy. Due to the large number of drugs available, it is necessary to identify the most effective therapies, whilst considering their side effects and impact on quality of life (QoL).

OBJECTIVES

To evaluate and compare the benefits and harms of first-line therapies for adults with advanced RCC, and to produce a clinically relevant ranking of therapies. Secondary objectives were to maintain the currency of the evidence by conducting continuous update searches, using a living systematic review approach, and to incorporate data from clinical study reports (CSRs).

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, conference proceedings and relevant trial registries up until 9 February 2022. We searched several data platforms to identify CSRs.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) evaluating at least one targeted therapy or immunotherapy for first-line treatment of adults with advanced RCC. We excluded trials evaluating only interleukin-2 versus interferon-alpha as well as trials with an adjuvant treatment setting. We also excluded trials with adults who received prior systemic anticancer therapy if more than 10% of participants were previously treated, or if data for untreated participants were not separately extractable.

DATA COLLECTION AND ANALYSIS

All necessary review steps (i.e. screening and study selection, data extraction, risk of bias and certainty assessments) were conducted independently by at least two review authors. Our outcomes were overall survival (OS), QoL, serious adverse events (SAEs), progression-free survival (PFS), adverse events (AEs), the number of participants who discontinued study treatment due to an AE, and the time to initiation of first subsequent therapy. Where possible, analyses were conducted for the different risk groups (favourable, intermediate, poor) according to the International Metastatic Renal-Cell Carcinoma Database Consortium Score (IMDC) or the Memorial Sloan Kettering Cancer Center (MSKCC) criteria. Our main comparator was sunitinib (SUN). A hazard ratio (HR) or risk ratio (RR) lower than 1.0 is in favour of the experimental arm.

MAIN RESULTS

We included 36 RCTs and 15,177 participants (11,061 males and 4116 females). Risk of bias was predominantly judged as being 'high' or 'some concerns' across most trials and outcomes. This was mainly due to a lack of information about the randomisation process, the blinding of outcome assessors, and methods for outcome measurements and analyses. Additionally, study protocols and statistical analysis plans were rarely available. Here we present the results for our primary outcomes OS, QoL, and SAEs, and for all risk groups combined for contemporary treatments: pembrolizumab + axitinib (PEM+AXI), avelumab + axitinib (AVE+AXI), nivolumab + cabozantinib (NIV+CAB), lenvatinib + pembrolizumab (LEN+PEM), nivolumab + ipilimumab (NIV+IPI), CAB, and pazopanib (PAZ). Results per risk group and results for our secondary outcomes are reported in the summary of findings tables and in the full text of this review. The evidence on other treatments and comparisons can also be found in the full text. Overall survival (OS) Across risk groups, PEM+AXI (HR 0.73, 95% confidence interval (CI) 0.50 to 1.07, moderate certainty) and NIV+IPI (HR 0.69, 95% CI 0.69 to 1.00, moderate certainty) probably improve OS, compared to SUN, respectively. LEN+PEM may improve OS (HR 0.66, 95% CI 0.42 to 1.03, low certainty), compared to SUN. There is probably little or no difference in OS between PAZ and SUN (HR 0.91, 95% CI 0.64 to 1.32, moderate certainty), and we are uncertain whether CAB improves OS when compared to SUN (HR 0.84, 95% CI 0.43 to 1.64, very low certainty). The median survival is 28 months when treated with SUN. Survival may improve to 43 months with LEN+PEM, and probably improves to: 41 months with NIV+IPI, 39 months with PEM+AXI, and 31 months with PAZ. We are uncertain whether survival improves to 34 months with CAB. Comparison data were not available for AVE+AXI and NIV+CAB. Quality of life (QoL) One RCT measured QoL using FACIT-F (score range 0 to 52; higher scores mean better QoL) and reported that the mean post-score was 9.00 points higher (9.86 lower to 27.86 higher, very low certainty) with PAZ than with SUN. Comparison data were not available for PEM+AXI, AVE+AXI, NIV+CAB, LEN+PEM, NIV+IPI, and CAB. Serious adverse events (SAEs) Across risk groups, PEM+AXI probably increases slightly the risk for SAEs (RR 1.29, 95% CI 0.90 to 1.85, moderate certainty) compared to SUN. LEN+PEM (RR 1.52, 95% CI 1.06 to 2.19, moderate certainty) and NIV+IPI (RR 1.40, 95% CI 1.00 to 1.97, moderate certainty) probably increase the risk for SAEs, compared to SUN, respectively. There is probably little or no difference in the risk for SAEs between PAZ and SUN (RR 0.99, 95% CI 0.75 to 1.31, moderate certainty). We are uncertain whether CAB reduces or increases the risk for SAEs (RR 0.92, 95% CI 0.60 to 1.43, very low certainty) when compared to SUN. People have a mean risk of 40% for experiencing SAEs when treated with SUN. The risk increases probably to: 61% with LEN+PEM, 57% with NIV+IPI, and 52% with PEM+AXI. It probably remains at 40% with PAZ. We are uncertain whether the risk reduces to 37% with CAB. Comparison data were not available for AVE+AXI and NIV+CAB.

AUTHORS' CONCLUSIONS

Findings concerning the main treatments of interest comes from direct evidence of one trial only, thus results should be interpreted with caution. More trials are needed where these interventions and combinations are compared head-to-head, rather than just to SUN. Moreover, assessing the effect of immunotherapies and targeted therapies on different subgroups is essential and studies should focus on assessing and reporting relevant subgroup data. The evidence in this review mostly applies to advanced clear cell RCC.

An unusual outcome of papillary renal cell carcinoma with lung metastases: a case report and review of literature

Background

Renal cell carcinoma (RCC) is a heterogeneous group of malignant epithelial tumors of the kidney. It accounts for more than 90% of all kidney cancers. However, papillary RCC is the second most common histologic subtype representing 10–15% of all RCCs. The mean age of presentation for papillary RCC ranges between 59 and 63 years but more importantly when RCC is diagnosed at a younger age, the possibility of an underlying hereditary kidney cancer syndrome should be considered. RCC potentially metastasizes to many different organs with lung being the commonest site accounting for 45.2%. The treatment for metastatic RCC is mostly multimodal for most patients. However, patients with untreated pulmonary metastases have been observed to have very poor prognosis with a 5-year overall survival rate of only 5% or even less and thus the need to report on the unusual outcome of our patient who had a metastatic disease.

Case presentation

The present study reports a papillary renal cell carcinoma with multiple lung metastases in a 31-year-old woman who presented with progressive right flank mass and pain with no chest symptoms. She underwent cytoreductive radical nephrectomy via a right subcostal incision. Patient, however, did not undergo metastasectomy nor palliative systemic therapy and was seen 5 years post-nephrectomy.

Conclusion

Our patient with metastatic RCC, without undergoing metastasectomy nor palliative systemic therapy, remained stable with 5-year progression-free survival post-cytoreductive nephrectomy.

Safety and tolerability of sorafenib in clear-cell renal cell carcinoma: a Phase III overview

This review summarizes the safety of sorafenib, an oral multikinase inhibitor, focusing on the randomized, placebo-controlled, Phase III Treatment Approaches in Renal Cancer Global Evaluation Trial (TARGET) in renal cell carcinoma, which formed the basis of the approval of sorafenib. Similar to other targeted agents, sorafenib acts primarily to induce disease stabilization, rather than tumor regression, suggesting that long-term administration is necessary. The tolerability of an agent is important in long-term treatment, and a predictable and manageable side-effect profile is advantageous. Although IL-2 and interferon have been standard care treatments for advanced renal cell carcinoma for over a decade, they are poorly tolerated. Targeted agents offer an alternative for patients with advanced renal cell carcinoma, as initial therapy or after failure of cytokine treatment.

Temsirolimus

Temsirolimus, an ester of sirolimus (rapamycin), selectively inhibits the kinase mammalian target of rapamycin (mTOR) and consequently blocks the translation of cell cycle regulatory proteins and prevents overexpression of angiogenic growth factors. It has been found to have antitumour activity in patients with relapsed or refractory mantle cell lymphoma (MCL). In addition, patients with advanced renal cell carcinoma (RCC) and a poor prognosis who received a once-weekly intravenous (IV) infusion of temsirolimus 25 mg experienced significant survival benefits compared with patients receiving standard interferon-α (IFN-α) therapy in a large phase III clinical study. In this study, median overall survival was 10.9 versus 7.3 months and objective response rates were 8.6% in temsirolimus recipients versus 4.8% IFN-α recipient group. Temsirolimus monotherapy recipients experienced significantly fewer grade 3 or 4 adverse events and had fewer withdrawals for adverse events than patients receiving IFN-α. The role of temsirolimus in sequential and combination therapy is yet to be found.

Oral adverse events associated with tyrosine kinase and mammalian target of rapamycin inhibitors in renal cell carcinoma: a structured literature review

BACKGROUND

Oral adverse events (OAEs) associated with multitargeted tyrosine kinase inhibitors (TKIs) and mammalian target of rapamycin inhibitors (mTORIs) are underestimated but frequent and novel presentations of mucosal manifestations. Because optimal antitumor activity requires maintaining the optimal dose, it is essential to avoid unintended treatment delays or interruptions.

METHODS

We review the reported prevalence and appearance of OAEs with TKIs and mTORIs and the current oral assessment tools commonly used in clinical trials. We discuss the correlations between OAEs and hand-foot skin reaction (HFSR) and rash.

RESULTS

The reported prevalence of oral mucositis/stomatitis of any grade is 4% for pazopanib, 28% for sorafenib, 38% for sunitinib, 41% for temsirolimus, and 44% for everolimus. Oral lesions associated with these agents have been reported to more closely resemble aphthous stomatitis than OM caused by conventional agents. In addition, these agents may result in symptoms such as oral mucosal pain, dysgeusia, and dysphagia, in the absence of clinical lesions. Because of these factors, OAEs secondary to targeted agents may be underreported. In addition, a correlation between OAEs and HFSR was identified.

CONCLUSIONS

OAEs caused by TKIs and mTORIs may represent dose-limiting toxicities, especially considering the fact that even low grades of OAEs may be troubling to the patient. We discuss how these novel AEs can be assessed because current mucositis assessment tools have limitations. Prospective studies investigating the pathogenesis, risk factors, and management of OAEs are needed in order to minimize the impact on patient's health-related quality of life.

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

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

[Targeted therapy of urological tumours. Experimental field or established therapeutic approach?]

Unlike conventional systemic chemotherapies, the aim of targeted therapeutic approaches is not to address general mechanisms involved in cellular replication. In contrast, they aim at such regulatory pathways that have been identified to be involved in the progression of human malignant disease. Whereas the application of targeted therapeutic modalities is well established for the treatment of metastatic renal cell cancer, only very few data on their clinical efficacy during the treatment of other urological tumours such as prostate and bladder cancer are currently available. The aim of this paper is to reflect on the current status regarding the relevance of targeted therapeutic approaches during the treatment of urological cancers of different origin.

Identification of a set of genes associated with response to interleukin-2 and interferon-α combination therapy for renal cell carcinoma through genome-wide gene expression profiling

Interleukin (IL)-2 and interferon (IFN)-α combination therapy for metastatic renal cell carcinoma (RCC) improves the prognosis for a subset of patients, while some patients suffer from severe adverse drug reactions with little benefit. To establish a method to predict responses to this combination therapy (approximately 30% response rate), the gene expression profiles of primary RCCs were analyzed using an oligoDNA microarray consisting of 38,500 genes or ESTs, after enrichment of the cancer cell population by laser micro-beam microdissection. The analysis of 10 responders and 18 non-responders identified 24 genes that exhibited significant differential expression between the two groups. In addition, the patients whose tumors did not express HLA-DQA1 or HLA-DQB1 molecules demonstrated poor clinical response. Exclusion of patients with tumors lacking either of these two genes is likely to improve the response rate to IL-2 and IFN-α combination therapy from 30 to 67%, indicating that a simple pretreatment test provides useful information with which to subselect patients with renal cancer in order to improve the efficacy of this treatment and reduce unnecessary medical costs.

Patient-based strategy for systemic treatment of metastatic renal cell carcinoma

There were only a few options 3 years ago to treat metastatic renal cell carcinoma (mRCC), a disease with a very poor prognosis. With the approval of targeted therapies for mRCC since December 2005, this situation has changed dramatically. Currently, oncologists can choose between several promising options to improve the longevity and quality of their patients' lives. A widely accepted treatment scheme for targeted therapies in mRCC does not yet exist. Based on a selective literature search, drawing on studies with six targeted therapies for mRCC, and including data from the latest American Society of Clinical Oncology (ASCO) and European Society for Medical Oncology (ESMO) Annual Meetings, this review introduces the available therapies, evaluates patient-specific criteria for their application and suggests an algorithm for a patient-based treatment scheme. Clinical experiences with sequential therapies are summarized and potential combination therapies discussed. In conclusion, the crucial criteria of the treatment scheme we propose are the tumor burden and the disease pace, as well as the quality of life of a patient. These define whether tumor control or tumor remission should be the primary therapeutic goal. This scheme suggests which kind of therapeutic sequence to pursue to optimize patient care in mRCC.

Updates on novel therapies for metastatic renal cell carcinoma

Metastatic renal cell carcinoma (RCC) poses one of the great therapeutic challenges in oncology. RCC is predominantly refractory to treatment with traditional cytotoxic chemotherapies, and until recently management options were limited to immunotherapy or palliative care. However, in the past few years we have experienced a sea change in the treatment of advanced RCC with the introduction of targeted therapies that derive their efficacy at least in part through alterations in tumor angiogenesis. The tyrosine kinase inhibitors sunitinib, pazopanib, and sorafenib, the monoclonal antibody bevacizumab (in combination with interferon-α), and the rapamycin analogs, temsirolimus and everolimus, are now approved agents in the United States for the treatment of metastatic RCC. Efforts to expand upon these successes include developing novel antiangiogenic agents, optimizing concomitant and sequential regimens, identifying predictors of response to specific treatments, and further dissecting the underlying molecular pathogenesis of RCC to reveal novel therapeutic targets.

Systemic therapy of kidney cancer: tyrosine kinase inhibitors, antiangiogenesis or IL-2?

The von Hippel-Lindau (VHL) tumor suppressor gene is mutated in at least 50% of sporadic clear-cell renal cell carcinoma (RCC). This leads to a pseudohypoxic state in which the pVHL complex does not degrade hypoxia-inducible factor. Subsequent intracellular hypoxia-inducible factor accumulation results in increased production of growth factors such as VEGF, responsible for angiogenesis, tumor proliferation and mitogenesis. Recently, a number of strategies have been designed to specifically target these pathways. The VEGF, its related receptor and the mammalian target of rapamycin (mTOR) signal transduction pathway, in particular, have been utilized as therapeutic targets. Clinical trials have demonstrated the survival benefit of these agents, particularly in clear-cell RCC. Today, sunitinib is recommended as first-line therapy for intermediate- or low-risk patients with metastatic RCC. Sorafenib is advised as second-line therapy, whereas temsirolimus is generally recommended as first-line treatment in high-risk patients. Everolimus is the new standard following sunitinib. High-risk patients appeared to benefit less than low-risk patients from bevacizumab plus IFN-alpha therapy. High-dose IL-2 has been proven effective in prolonging progression-free survival or overall survival, depending on risk group selection criteria. Although novel agents show a consistent effect as measured by objective response, no currently available data demonstrate that these agents will cure any patient.

Sorafenib tosylate in advanced kidney cancer: past, present and future

The objective of this paper was to review the development of sorafenib tosylate in kidney cancer. The MedLine database, the Proceedings of the Annual American Society of Clinical Oncology meeting, as well as those of other key international meetings were extensively searched to identify relevant publications. Furthermore, the authors' direct experience with the drug was taken into account when commenting on the results retrieved. Sorafenib is a multikinase inhibitor that targets VEGF and PDGF receptors, other kinases, as well as the serine-threonine kinase Raf. Following early signs of activity from phase I and II studies, it has been shown to improve survival of pretreated advanced kidney cancer patients within a placebo-controlled, randomized, phase III trial, leading to its approval both in the United States and in Europe. Its activity has been subsequently confirmed in a real-world population by two expanded access programs performed globally, but not in a first-line setting; it also proved to be non-cross-resistant with two other molecularly targeted agents. Finally, its toxicity profile, which is acceptable and highly predictable, makes sorafenib appealing for combination treatments, especially with other molecularly targeted agents. Despite having been already demonstrated to be active in kidney cancer, the exact role of sorafenib in the first-line setting, in patients who have failed other molecularly targeted agents, and especially in combination with other agents, deserves further, prospective, studies.

Temsirolimus

Temsirolimus, an ester of sirolimus (rapamycin), selectively inhibits the kinase mammalian target of rapamycin and consequently blocks the translation of cell cycle regulatory proteins and prevents overexpression of angiogenic growth factors. Patients with advanced renal cell carcinoma (RCC) and a poor prognosis who received a once-weekly intravenous (IV) infusion of temsirolimus 25 mg, experienced significant survival benefits when compared with patients receiving standard interferon-alpha (IFNalpha) therapy in a large phase III clinical study. In this study, median overall survival was 10.9 vs. 7.3 months and objective response rates were 8.6% in temsirolimus recipients vs. 4.8% IFNalpha recipient group.Temsirolimus monotherapy recipients experienced significantly fewer grade 3 or 4 adverse events and had fewer withdrawals for adverse events than patients receiving IFNalpha.

Renal cell carcinoma with an emphasis on drug therapy of advanced disease, part 1

PURPOSE

The diagnosis, staging, and management of renal cell carcinoma (RCC) are reviewed. The mechanism, pharmacokinetics, toxicity, clinical activity, and application of molecularly targeted agents in RCC are emphasized.

SUMMARY

RCC is the eighth most commonly diagnosed malignancy in the United States. The most common signs and symptoms are gross hematuria, flank pain, and the presence of a flank mass. Localized disease is found in about 55% of patients, 19% of patients have locally advanced disease, and 20% of patients have metastatic disease. Surgical resection is the mainstay of therapy for stage I-III RCC. The pharmacotherapy of RCC is undergoing significant change. Standard therapy used to include the cytokines interferon alfa and aldesleukin. High-dose aldesleukin is used to treat select patients. Its major value is the durability of responses in the few patients who achieve a complete remission. However, cytokines have been largely displaced by sorafenib tosylate, sunitinib malate, and temsirolimus due to their lower rates of toxicity and positive effects on progression-free survival. Bevacizumab has also shown activity in patients with advanced disease. Estimated five-year survival rates for patients with RCC are 89.6% for localized disease, 60.8% for regional disease, and 9.5% for patients with distant metastases. Studies are currently under way to assess the activity of combinations of available agents and new targeted agents as adjuvant therapy and for the management of advanced RCC.

CONCLUSION

The options available for the management of advanced RCC have expanded considerably in the past five years with the advent of molecularly targeted therapies.

Metastatic renal cell carcinoma: recent advances in the targeted therapy era

CONTEXT

The treatment of metastatic renal cell carcinoma (mRCC) has recently evolved from being predominantly cytokine based to being grounded in the use of targeted agents.

OBJECTIVE

To analyse current evidence on the medical management of mRCC.

EVIDENCE ACQUISITION

The PubMed and Medline databases were searched for articles published as of 15 July 2009. Only articles published in English were considered. The search terms were metastatic renal cell cancer, targeted therapy, and immunotherapy. Proceedings from the 2000-2009 conferences of the American Society of Clinical Oncology, the American Urological Association, and the European Association of Urology were also searched for relevant abstracts.

EVIDENCE SYNTHESIS

Sunitinib has recently emerged as a front-line standard of care in mRCC. Temsirolimus is considered a first-line therapy for patients with poor risk features. Bevacizumab/interferon is likely to be the next U.S. Food and Drug Administration-approved first-line treatment. The use of sorafenib has moved toward second-line and later therapy. Everolimus was the first agent to show clinical benefit post-tyrosine kinase inhibitor failure in a phase 3 study and is considered the standard of care in this setting. Temsirolimus provided benefit to patients with non-clear-cell histology. In preliminary results, a favourable risk-benefit ratio has been shown with pazopanib and axitinib as first- and second-line treatment. Until combination therapy is clearly shown to be superior to monotherapy, it should be used in the context of a clinical trial. Deciding which is the best sequence to use in mRCC patients remains up to the best judgement of the treating physician. Cytoreductive nephrectomy in the presence of metastatic disease is often indicated as part of an integrated management strategy.

CONCLUSIONS

Given considerable advances in understanding the biology of mRCC, several new drugs have recently been developed, offering an increasing number of treatment options. A treatment algorithm based on the best available evidence so far can be therefore postulated, though it continues to evolve as data from ongoing trials become available.

Metastatic Renal Cell Carcinoma: Many Treatment Options, One Patient

There has been a recent expansion of therapeutic options in metastatic renal cell carcinoma (RCC) targeted at the vascular endothelial growth factor and mammalian target of rapamycin pathways, which are fundamental to the biology of RCC. These treatment options have similarities in antitumor effect but also important differences in regards to clinical effects, toxicity and patient populations in which they have been investigated. Further, issues regarding the role of debulking nephrectomy, timing of therapy, and appropriate sequencing of agents have emerged as clinically relevant. There are thus potentially many different treatment approaches to each metastatic RCC patient. This review discusses how to integrate the available data regarding targeted therapy in metastatic RCC into personalized cancer care.

Treatment of metastatic renal cell carcinoma

PURPOSE

To review the treatment of metastatic renal cell carcinoma (RCC), including the use of new targeted therapies.

METHODS

A search of MEDLINE (1966 to August 2008) and American Society of Clinical Oncology Meeting abstracts (2005 to May 2008) was preformed using the search terms bevacizumab, everolimus, interferon-alfa (IFN-alpha), interleukin-2 (IL-2), sorafenib, sunitinib, temsirolimus, and RCC. Articles most pertinent to the treatment of metastatic RCC are reviewed.

RESULTS

The treatment of metastatic RCC has undergone a paradigm shift over the past 5 years from biologic response modifiers to new targeted therapies. Historically, response rates for the biological response modifiers, aldesleukin (IL-2), and IFN-alpha were approximately 15%. Recently, three targeted agents, sorafenib, sunitinib, and temsirolimus have been approved for the treatment of RCC. Additionally, bevacizumab has been investigated and shown to increase progression free survival in RCC. IL-2 remains the only agent to induce complete, durable remissions; however, many patients are not eligible for this therapy. Newer agents (sorafenib, sunitinib, and temsirolimus) have shown to be superior to IFN-alpha or placebo and bevacizumab combined with IFN-alpha has shown activity when compared to IFN-alpha alone. Unlike IL-2, the greatest benefit obtained with targeted therapies is in achieving stable disease (SD). Despite their benefit, targeted therapies have never been compared with each other in clinical trials and choosing the most appropriate agent remains challenging. To date, the optimal sequence or combination of treatments has not been defined; however, everolimus has recently demonstrated activity in patients progressing on targeted therapy.

CONCLUSIONS

IL-2 remains the most active regimen in inducing complete responses; however, its use is accompanied by substantial morbidity and is limited to those with a good performance status. Targeted therapies are also efficacious in the treatment of RCC, with the major benefit being induction of SD. Future research will better define the sequencing of therapies, as well as, explore the activity of novel combination regimens.

Renal cell carcinoma

Considerable progress has been made in the treatment of patients with renal cell carcinoma, with innovative surgical and systemic strategies revolutionising the management of this disease. In localised disease, partial nephrectomy for small tumours and radical nephrectomy for large tumours continue to be the gold-standard treatments, with emphasis on approaches that have reduced invasiveness and preserve renal function. Additionally, cytoreductive nephrectomy is often indicated before the start of systemic treatment in patients with metastatic disease as part of integrated management strategy. The effectiveness of immunotherapy, although previously widely used for treatment of metastatic renal cell carcinoma, is still controversial, and is mainly reserved for patients with good prognostic factors. Development of treatments that have specific targets in relevant biological pathways has been the main advance in treatment. Targeted drugs, including inhibitors of the vascular endothelial growth factor and mammalian target of rapamycin pathways, have shown robust effectiveness and offer new therapeutic options for the patients with metastatic disease.

Systemic therapy for metastatic renal cell carcinoma

Renal cell cancer (RCC) is the most common form of cancer of the kidney and accounts for approximately 44,000 cases per year in the United States. Historically, only immunotherapy showed activity in metastatic RCC. The improved survival and quality of life for patients with metastatic RCC over the last several years are direct results of advances made in understanding the development of RCC. Three targeted therapies-sunitinib, sorafenib, and temsirolimus-have been approved for use in the United States recently. Current research is aimed at developing new drugs and combining available drugs to improve upon the responses and survival seen with approved single agents.

Metastatic renal cell cancer treatments: an indirect comparison meta-analysis

BACKGROUND

Treatment for metastatic renal cell cancer (mRCC) has advanced dramatically with understanding of the pathogenesis of the disease. New treatment options may provide improved progression-free survival (PFS). We aimed to determine the relative effectiveness of new therapies in this field.

METHODS

We conducted comprehensive searches of 11 electronic databases from inception to April 2008. We included randomized trials (RCTs) that evaluated bevacizumab, sorafenib, and sunitinib. Two reviewers independently extracted data, in duplicate. Our primary outcome was investigator-assessed PFS. We performed random-effects meta-analysis with a mixed treatment comparison analysis.

RESULTS

We included 3 bevacizumab (2 of bevacizumab plus interferon-a [IFN-a]), 2 sorafenib, 1 sunitinib, and 1 temsirolimus trials (total n = 3,957). All interventions offer advantages for PFS. Using indirect comparisons with interferon-alpha as the common comparator, we found that sunitinib was superior to both sorafenib (HR 0.58, 95% CI, 0.38-0.86, P = < 0.001) and bevacizumab + IFN-a (HR 0.75, 95% CI, 0.60-0.93, P = 0.001). Sorafenib was not statistically different from bevacizumab +IFN-a in this same indirect comparison analysis (HR 0.77, 95% CI, 0.52-1.13, P = 0.23). Using placebo as the similar comparator, we were unable to display a significant difference between sorafenib and bevacizumab alone (HR 0.81, 95% CI, 0.58-1.12, P = 0.23). Temsirolimus provided significant PFS in patients with poor prognosis (HR 0.69, 95% CI, 0.57-0.85).

CONCLUSION

New interventions for mRCC offer a favourable PFS for mRCC compared to interferon-alpha and placebo.

[Antiangiogenics: new therapeutic standards in metastatic kidney cancer]

Since 2004, the treatment of metastatic renal cell carcinoma is in deep mutation. Before, the Management was mostly relying on the use of cytokines in association with radical nephrectomy. From 2004, studies of new antiangiogenic molecules, acting on the pVHL-HIF way, VEGF, PDGF or tyrosine-kinase receptors have modified the management of metastatic patients. Antiangiogenic agents improve progression-free survival as shown with sunitinib, in first line treatment, or sorafenib, as second line treatment. The m-TOR inhibitors (Temsirolimus), can be used with a benefit on overall survival in case of poor prognosis renal cell carcinoma or non clear cell carcinoma. Lastly, bevacizumab, an antibody re-combining humanized monoclonal, is able to target VEGF. Side effects are different for each molecule and are not negligible. Nevertheless, the place of these molecules have to be defined in the sequence of the treatment.

Adjuvant therapy for renal cell carcinoma

Currently, the management of localized renal cell carcinoma (RCC) is surgical. Unfortunately, many cases of high-risk RCC recur following resection and develop metastatic disease, an event that usually results in death. Because previous attempts to improve survival with adjuvant therapy have been unsuccessful, the US Food and Drug Administration's approval of three new agents for metastatic RCC has generated renewed interest in evaluating agents in the adjuvant setting for high-risk RCC. This article discusses the rationale for the use of these and other novel agents and reviews currently ongoing adjuvant trials as well as considerations for the development of new trials for adjuvant therapies.

Can tyrosine kinase inhibitors be discontinued in patients with metastatic renal cell carcinoma and a complete response to treatment? A multicentre, retrospective analysis

BACKGROUND

Discontinuation of treatment with tyrosine kinase inhibitors (TKIs) and readministration in case of recurrence could improve quality of life (QoL) and reduce treatment costs for patients with metastatic renal cell carcinoma (mRCC) in which a complete remission (CR) is achieved by medical treatment alone or with additional resection of residual metastases.

OBJECTIVE

To evaluate whether TKIs can be discontinued in these selected patients with mRCC.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective analysis of medical records and imaging studies was performed on all patients with mRCC treated with TKIs (n=266) in five institutions. Patients with a CR under TKI treatment alone or with additional metastasectomy of residual disease following a partial response (PR), in which TKIs were discontinued, were included in the analysis. Outcome criteria analysed were time to recurrence of previous metastases, occurrence of new metastases, symptomatic progression, improvement of adverse events, and response to reexposure to TKIs.

INTERVENTIONS

Sunitinib 50mg/day for 4 wk on and 2 wk off, sorafenib 800mg/day.

MEASUREMENTS

Response according to Response Evaluation Criteria in Solid Tumours (RECIST).

RESULTS AND LIMITATIONS

We identified 12 cases: 5 CRs with sunitinib, 1 CR with sorafenib, and 6 surgical CRs with sunitinib followed by residual metastasectomy. Side-effects subsided in all patients off treatment. At a median follow-up of 8.5 mo (range: 4-25) from TKI discontinuation, 7 of 12 patients remained without recurrence and 5 had recurrent disease, with new metastases in 3 cases. Median time to progression was 6 mo (range: 3-8). Readministration of TKI was effective in all cases. The study is limited by small numbers and retrospective design.

CONCLUSIONS

Discontinuation of TKI in patients with mRCC and CR carries the risk of progression with new metastases and potential complications. Further investigation in a larger cohort of patients is warranted before such an approach can be regarded as safe.

Recent advances in the treatment of renal cell carcinoma and the role of targeted therapies

Immunotherapy confers a small but significant overall survival advantage in metastatic renal cell carcinoma (RCC) but only for the minority of patients, i.e. the 20% with good prognostic features. Recent developments in the molecular biology of renal cell carcinoma have identified multiple pathways associated with the development of this cancer. Several strategies have been investigated targeting these pathways, with significant clinical benefits shown in early studies. New agents including the small molecule targeted inhibitors sunitinib, sorafenib and temsirolimus, and the monoclonal antibody bevacizumab have shown anti-tumour activity in randomised clinical trials and have become the standard of care for most patients. Sunitinib and temsirolimus have shown significant improvements in progression-free survival (sunitinib) and overall survival (temsirolimus) in separate phase III studies in the first-line setting when compared with interferon-alpha. Sorafenib has demonstrated prolonged progression-free survival in a phase III study in comparison with placebo in the second-line setting. More recently two phase III studies have compared bevacizumab and interferon-alpha with interferon-alpha alone. Both studies showed a statistically significant improvement in progression-free survival for the combination arm. Additional studies are needed to optimise the use of these agents by identifying those patients who most benefit and elucidating the best way of delivering them, either in combination or as sequential single agents.

Renal cell carcinoma

PURPOSE OF REVIEW

The recent contributions to renal cell carcinoma in the fields of molecular biology and the expanded use of molecularly targeted agents will be reviewed. This study is intended to update prognostic and therapeutic decision-making data and provide perspective on advances in understanding the molecular biology of this disease.

RECENT FINDINGS

Updates to the currently used prognostic algorithms for renal cell carcinoma are needed, and recently verified prognostic nomograms will be discussed. This comes in the wake of numerous advances in the use of molecularly targeted drugs, which will be reviewed. Finally, advancements in understanding the biology of renal cell carcinoma include the discovery of von Hippel-Lindau associated mechanisms involved in renal cyst formation and renewed appreciation for the influence of this pathway on the tumor cell glucose utilization profile.

SUMMARY

Renal cell carcinoma continues to evolve swiftly with the approval of new agents and the maturation of clinical trials to provide relevant structure to treatment decisions. This study will give an overview of the latest concepts in the epidemiology and biology of renal cell carcinoma and provide current surgical and systemic updates for managing renal cell carcinoma.

Update on the medical treatment of metastatic renal cell carcinoma

CONTEXT

Metastatic renal cell carcinoma (mRCC) has long been treated only by immunotherapy with good results only in a small population of patients. In recent years, major improvements in treatment possibilities have occurred with the advent of anti-angiogenic drugs. In the past 2 yr, pivotal phase III trials have confirmed this major breakthrough by increasing the progression-free survival rates and/or overall survival rates provided by sunitinib, sorafenib, and bevacizumab, and more recently by the mTOR (mammalian target of rapamycin) inhibitors temsirolimus and everolimus.

OBJECTIVE

To update the previous review on smart drugs published in the European Journal in 2006 (Patard JJ, et al. Understanding the importance of smart drugs in renal cell carcinoma. Eur Urol 2006; 49:633-43).

EVIDENCE ACQUISITION

Critical review of published literature 2006-2008 (Pubmed website search words: renal cell carcinoma and/or targeted therapy and prospective trials) and more recent meeting abstracts (American Society of Clinical Oncology 2007). Quality assessment included prospective phase I-III trials and critical evaluations with low numbers of patients, retrospective analyses, and slide presentations of meeting abstracts.

EVIDENCE SYNTHESIS

This review presents the current situation and provides more recent data on sequential treatment, the association of targeted drugs, and the treatment of non-clear-cell histologies.

CONCLUSIONS

Treatment of mRCC with targeted therapy centers on at least two major pathways: angiogenesis and mTOR involving inhibiting drugs that may be used alone, in combination, or sequentially.

Targeted therapy for advanced renal cell carcinoma

BACKGROUND

Advanced renal cell carcinoma has been resistant to drug therapy of different types and new types of drug therapy are needed. Targeted agents inhibit known molecular pathways involved in cellular proliferation and neoangiogenesis, the induction by the tumour of host microvascular networks. Angiogenesis is of special interest in the clear cell histologic subtype of renal cancer because of its vascularity and constitutively activated hypoxia-inducible path in the majority of tumours.

OBJECTIVES

1) To provide a systematic review of studies testing targeted agents.2) To identify the type and degree of clinical benefit, if any, of targeted agents over the prior standard of care, particularly any impact on overall survival.

SEARCH STRATEGY

1) Electronic search of CENTRAL, MEDLINE and EMBASE databases.2) Hand search of international cancer meeting abstract and other sources specified in the protocol.

SELECTION CRITERIA

Randomized controlled studies of targeted agents in patients with advanced renal cell cancer reporting major remission rate or overall survival by allocation. Progression-free survival (PFS) was adopted as an additional outcome because PFS was a commonly chosen primary outcome, and because several pivotal studies allowed crossover from the control to the investigational arm after closure to accrual thereby making overall survival a problematic endpoint.

DATA COLLECTION AND ANALYSIS

Nineteen fully eligible studies tested ten different targeted agents (Table 04). One additional study was excluded because no outcome data by allocation have been reported (Hutson 2007). For purposes of comparison, the studies were divided into three groups: Group 1 studies compared different doses of the same agents; Group 2 studies examined the impact of targeted agents in patients who had received prior cytokine or other systemic therapy; and Group 3 studies tested targeted agents in systemically naive patients, either against standard interferon-alfa or against another control therapy. Meta-analysis was not utilized because there were very few situations where the same agents had been tested in the same group in more than one study.

MAIN RESULTS

In systemically untreated patients in studies using subcutaneous interferon-alfa as control therapy, the major findings were: 1) An improvement in overall survival has been demonstrated only with the use of weekly intravenous temsirolimus in patients with unselected renal cancer histology and adverse prognostic features (median survival 10.9 months versus 7.3 months for temsirolimus or interferon-alfa respectively, HR 0.73, P = 0.008 log rank, Hudes 2007). However, the chance of major remission was low and not improved with temsirolimus. 2) In patients with mostly good or intermediate prognostic risk with clear cell renal cancer, oral sunitinib improves the chance of major remission, the probability of symptomatic improvement, and freedom from disease progression (Motzer 2007); in a similar setting, the addition of biweekly intravenous bevacizumab to interferon-alfa also improved the chance of major remission and prolonged progression-free survival (Escudier 2007b); overall survival had not changed at the time of interim reporting of either study. In patients with clear cell renal cancers who had failed prior cytokine therapy, oral sorafenib gives a better quality of life than placebo as well as improved chance of being free of disease progression; overall survival may have improved but is hard to evaluate because of crossover of placebo-assigned patients after the study closed to accrual (Escudier 2007a).

AUTHORS' CONCLUSIONS

Based on less than a decade of experience, some targeted agents with specified molecular targets have demonstrated clinically useful benefits over the previous standard of care for patients with advanced renal cancer. Much more research is required to fully establish the role of targeted agents in this condition.