Sarcomatoid transitional cell carcinoma of the renal pelvis. A report of five cases with clinical, pathological, immunohistochemical and DNA ploidy analysis.

Sarcomatoid transitional cell carcinoma of the renal pelvis is a rare neoplasm with only 7 well illustrated examples reported. These tumours can assume a partial or complete spindle cell pattern of growth, leading to the erroneous classification as sarcomas. We describe the clinic-pathologic features of five additional examples of sarcomatoid carcinoma of the renal pelvis observed in three males and two females. The age ranged from 65-to-82 years-old (mean 71.6). All these patients were treated by nephrectomy and died of disease between 6 and 20 months (mean 11.2) after the onset of symptoms. An immunohistochemical study demonstrated coexpression of keratins, epithelial membrane antigen and vimentin. The image DNA ploidy of all the tumours showed an aneuploid pattern.