Flow cytometric analysis of DNA ploidy, cell cycle and cytomorphometry in sarcomatoid renal cell carcinoma

In 5 patients with sarcomatoid renal cell carcinoma, the nuclear DNA content and size were determined by flow cytometry (FCM), and the prognostic value of DNA ploidy, the percentage of S-phase cells (SPF), and the ratio of modal nuclear size with clinicopathologic behavior was analyzed. Age and clinical stage have been shown to have a strong correlation with prognosis. Older patients with a high stage of cancer had poor outcome with a shorter survival time. In all 60% of the tumors were aneuploid. Tumor invasiveness was related to DNA ploidy. With increasing stage, the overall incidence of aneuploid rises. One alive patient had diploid DNA while 75% of the patients who died of sarcomatoid renal cell carcinomas had aneuploid DNA. Diploid sarcomatoid renal cell carcinomas show significantly lower SPF than aneuploid tumors. There was no significant association between the modal nuclear size and the invasiveness of tumors or survival time. This study suggests that FCM analysis of tumor DNA content and cell cycle could be regarded as an additional prognostic determinant of sarcomatoid renal cell carcinoma.