Renal cell carcinoma: evolving approaches to advanced non-clear cell carcinoma

Sunitinib in the treatment of advanced solid tumors

Sunitinib is an oral multikinase inhibitor that blocks the vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR) alpha and beta, c-kit, and other receptors. These attributes have proven to be efficacious in the treatment of metastatic renal cell carcinoma (RCC), unresectable gastrointestinal stromal tumors (GIST), and well-differentiated advanced pancreatic neuroendocrine tumors (PNET). Though activity has been reported in other tumor types, phase III trials have not yet demonstrated improved survival outcomes in these cancers. Most side effects including hypertension, hand-foot syndrome, and diarrhea are generally well manageable. This review will detail the preclinical data leading up to the results of the pivotal phase III clinical trials that have led to the widespread use of sunitinib in advanced RCC, GIST, and PNET.

An adjusted indirect comparison of everolimus and sorafenib therapy in sunitinib-refractory metastatic renal cell carcinoma patients using repeated matched samples

OBJECTIVE

To date, no trial data exist comparing treatment outcomes for everolimus versus sorafenib. The current analysis indirectly compares the overall survival (OS) benefit of everolimus and sorafenib as second-line treatment options.

RESEARCH DESIGN AND METHODS

A single-arm sorafenib study is selected as a basis to match an everolimus sunitinib-refractory subpopulation of the RECORD-1 trial. Only patients with clear cell histology are included. An adjusted matching approach is taken where 1000 repeated random samples matched to the sorafenib population on risk score distribution are produced, and a 95% CI around the mean of all sampled median OS is generated.

MAIN OUTCOME MEASURES

The main outcome measures include adjusted median OS and progression-free survival.

RESULTS

In all, 45 clear cell histology sorafenib patients and 1000 samples of N=41 sunitinib-refractory everolimus patients are considered for analysis. After adjusted matching, the estimated median OS benefit is 32.0 [corrected] weeks (95% CI: 22, 64) and 81.5 weeks (95% CI:78, 86) for sorafenib and everolimus patients, respectively.

CONCLUSION

Results suggest that sunitinib-refractory metastatic renal cell carcinoma patients treated with everolimus may experience significantly improved OS outcomes compared to those treated with sorafenib. However, because this is not a randomized controlled trial, the results should be interpreted as those from an observational study.

Sunitinib

Sunitinib is an oral multikinase inhibitor that blocks the vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR) alpha and beta, c-kit, and other receptors. These attributes have proven to be efficacious in the treatment of metastatic renal cell carcinoma (RCC) and unresectable gastrointestinal stromal tumors (GIST). Most side effects, including hypertension, hand-foot syndrome, and diarrhea are generally well manageable. Clinical trials are underway to determine the efficacy of sunitinib in other tumor types including metastatic breast, colorectal, and lung cancers. This chapter will detail the preclinical data leading to the results of the pivotal phase III clinical trials that have led to the widespread use of sunitinib in metastatic RCC and advanced GIST.