[Non-clear cell renal cell carcinoma]

Area of Science:

• Oncology
• Nephrology

Context:

• Non-clear cell renal cell carcinomas (nccRCC) represent a heterogeneous group of kidney cancers, comprising 20-25% of all renal tumors.
• Numerous rare subtypes exist, each with unique histological and molecular characteristics, often representing less than 1% of cases.

Purpose:

• To review current treatment recommendations for localized and advanced non-clear cell renal cell carcinomas.
• To present data on systemic therapies utilized for nccRCC subtypes.
• To highlight the need for entity-specific treatment guidelines and further research.

Summary:

• Current treatment strategies for nccRCC are largely extrapolated from clear cell renal cell carcinoma (ccRCC) due to a lack of large-scale studies for rare subtypes.
• Treatment options include monotherapies with tyrosine kinase inhibitors (TKIs) or mTOR inhibitors (for specific subtypes like chromophobe RCC), and combination therapies such as immune checkpoint inhibitor (ICI)/ICI or TKI/ICI.
• Treatment decisions are guided by risk factors and individual patient considerations.

Impact:

• The absence of entity-specific guidelines and randomized trials for nccRCC creates uncertainty in optimal treatment selection.
• Standardizing treatment approaches similar to ccRCC is a current practice, but may not be universally optimal.
• Urgent need for randomized clinical trials to establish evidence-based guidelines for rare nccRCC subtypes to improve patient outcomes.