sarcomatoid transrormation of chromophobe renal cell carcinoma

Chromophobe renal cell carcinoma is rare and represents around 5.9% of all renal cell carcinoma. it can have a wide range of age at the time of presentation but usually occurs between second to fourth decades of life (1). grossly, chromophoberenal cell carcinoma is usually well circumscribed and solid with yellowish brown color (2). microscopically, the tumor is characterized by large plant like cells with welldefined cell membranes and transparent or small cells with an eosinophilic cytoplasm and perinuclear clearing (3). this type of renal cell carcinoma is well known for its rather good prognosis.