Paired Specimens.

The author discusses the phenotype reflectivity of renal cell carcinoma (RCC) with sarcomatoid change. She mentions that RCCs having these features contain spindle cells with high-grade pleomorphic nuclei which can resemble the appearance of primary sarcomas. She refers to the study of Shuch and colleagues regarding the clonality and phenotype of RCCs. An overview of the study is offered which emphasized on various important questions including the percentage of sarcomatoid features.