Chromophobe Renal Cell Carcinoma With Sarcomatoid Differentiation: A Case Report and Review of the Literature.

Chromophobe renal cell carcinoma is a rare entity with an excellent prognosis compared with clear renal cell carcinoma and is characterized by distinct molecular and genetic specificity. The presence of a sarcomatoid component is an uncommon phenomenon, which indicates a high risk of metastasis and a poor prognosis. We present the case of a 44-year-old patient with chromophobe renal cell carcinoma with a sarcomatoid component. Therapeutic management presents a significant challenge given the absence of standards of care for this rare entity. The current treatments are based on vascular endothelial growth factor tyrosine kinase inhibitors, mammalian target of rapamycin pathway inhibitors, and immune checkpoint inhibitors. Close monitoring based on clinical, biological, and radiological examinations is necessary for rapid and appropriate interventions. Moreover, this histological variant represents a major clinical challenge, not only because of its aggressive behavior but also due to the absence of specific clinical manifestations and its frequent incidental discovery at an advanced stage, further complicating early diagnosis and management.