EVIDENCE SYNTHESIS The systematic review showed an absence of evidence for treating RKCs , with data only supporting sunitinib or MET inhibitors for some specific subtypes .
PATIENT SUMMARY Patients confronted with rare kidney cancers are often treated the same way as clear-cell renal cell carcinoma patients , despite little evidence from r and omized trials .
Molecular characterization of tumors to stratify patients may improve outcomes .
CONTEXT The European Association of Urology Renal Cell Carcinoma Guideline Panel recently conducted a systematic review of treatment options for patients with advanced non-clear-cell renal cell carcinomas ( RCCs ) , which showed a substantial lack of evidence for management recommendations .
OBJECTIVE To improve the outcomes of patients with rare kidney cancers ( RKCs ) , we performed a subsequent unstructured review to determine current treatment strategies and druggable pathways , involving key stakeholders with a global perspective to generate recommendations .
Systemic Therapy for Non-Clear Cell Renal Cell Carcinoma.
Treatment options for metastatic clear cell renal cell carcinoma ( ccRCC ) have evolved markedly over the past decade , with multiple targeted therapies approved for the disease . In contrast , little improvement has been made in the management of metastatic non-clear cell RCC ( nccRCC ) . Non-clear cell disease is an umbrella term that encompasses multiple biologically distinct entities , including but not limited to papillary , chromophobe , and sarcomatoid RCC . To date , prospect i ve studies have largely explored treatments for ccRCC ( e.g. , VEGF- and mTOR-directed therapies ) in trials that aggregate non-clear cell histologies . However , the studies do not acknowledge the varying biology of each non-clear cell subtype . Emerging studies in nccRCC should examine individual histologies and apply biologically relevant therapies . An example of this is SWOG 1500 , a r and omized phase II study that will compare a  VEGF-inhibitor  to one of three  MET-directed therapies  in patients with metastatic papillary RCC . Until the biologic diversity of nccRCC is appreciated , outcomes are likely to remain dismal
EVIDENCE SYNTHESIS The systematic review showed an absence of evidence for treating RKCs , with data only supporting sunitinib or MET inhibitors for some specific subtypes .
PATIENT SUMMARY Patients confronted with rare kidney cancers are often treated the same way as clear-cell renal cell carcinoma patients , despite little evidence from r and omized trials .
Molecular characterization of tumors to stratify patients may improve outcomes .
CONTEXT The European Association of Urology Renal Cell Carcinoma Guideline Panel recently conducted a systematic review of treatment options for patients with advanced non-clear-cell renal cell carcinomas ( RCCs ) , which showed a substantial lack of evidence for management recommendations .
OBJECTIVE To improve the outcomes of patients with rare kidney cancers ( RKCs ) , we performed a subsequent unstructured review to determine current treatment strategies and druggable pathways , involving key stakeholders with a global perspective to generate recommendations .