Flow cytometric analysis of nuclear deoxyribonucleic acid content in renal cell carcinoma

Kang, Jeung Ki; Yoon, Jong Byung

Abstract

The deoxyribonucleic acid content was determined in 50 cases of renal cell carcinoma by means of flow cytometric analysis of paraffin-embedded specimens. Of these, 22 cases (44%) were diploid and 28 cases (56% ) were aneuploid. The incidence of aneuploid pattern according to histological grade was 38% in high grade and 75% in low grade with statistical difference. The ploidy status did not correlate with tumor stage, tumor cell type or presence of microvascular invasion. Of 22 cases in which two separate specimens were analyzed from each primary tumor. intratumoral heterogeneity of ploidy status was observed in 9 cases(41%). Of 13 cases in which specimens from both primary tumor and regional metastatic lesions were analyzed, intertumoral heterogeneity was observed in 8 cases(62%). A close correlation between tumor stage and prognosis was observed. The prognostic difference according to histological grade. tumor cell type or presence ol microvascular invasion was statistically unacceptable. The 5-year survival rate according to ploidy status was 77% in diploid tumors and 47% in aneuploid tumors with statistical significance, but no significant difference in overall survival was observed. Among the patients without metastasis of renal cell carcinoma. those with diploid tumors had better prognoses in comparison to those with aneuploid tumors. Conclusively, DNA content in renal cell carcinoma analyzed by FCM had shown the coexistence of intratumoral and intertumoral heterogeneities and is considered to be an important prognostic stratifier in renal cell carcinoma without metastasis.