Well differentiated clear cell renal carcinoma: significance of nuclear deoxyribonucleic acid patterns studied by flow cytometry.

Nuclear deoxyribonucleic acid ploidy was determined in 206 samples of well differentiated clear cell renal carcinoma via a previously described technique on paraffin-embedded archival material. Grade 2 tumors had a higher incidence of abnormal deoxyribonucleic acid patterns than grade 1 tumors. Of stage 1 well differentiated clear cell renal tumors 60 per cent had a normal deoxyribonucleic acid histogram pattern, whereas 67 per cent of higher stage tumors had an abnormal pattern. The existence of abnormal nuclear deoxyribonucleic acid histogram patterns in the primary tumor tissue had a significant correlation with subsequent development of metastatic disease, independent of tumor grade and stage. The 10-year actuarial survival rate was 62 per cent for patients with normal deoxyribonucleic acid histograms and 37 per cent for patients with abnormal patterns. These results demonstrate that nuclear deoxyribonucleic acid ploidy measured by flow cytometry is an important variable in the classification and determination of prognosis for patients with clear cell renal carcinoma.