Comparison of chromosomal aberrations detected by fluorescence in situ hybridization with clinical parameters, DNA ploidy and Ki 67 expression in renal cell carcinoma

Abstract

To evaluate the significance of chromosomal aberrations in renal cell carcinoma, fluorescence in situ hybridization (FISH) was used to determine its prevalence and correlation with clinical parameters of malignancy. In addition, correlation of chromosomal aberration with Ki 67 expression was analysed. We performed FISH with chromosome-specific DNA probes, and the signal number of pericentromeric sequences on chromosomes 3, 7, 9 and 17 was detected within interphase nuclei in touch preparations from tumour specimen. The incidence of loss of chromosome 3 was significantly higher than those of chromosomes 7, 9 and 17 (P < 0.001, P = 0.03 and P < 0.001 respectively). Hyperdiploid aberration of chromosomes 3 and 17 was significantly correlated with tumour stage (P = 0.03, P = 0.02 respectively), whereas hyperdiploid aberration of chromosome 9 was associated with nuclear grade (P = 0.04). Disomy of chromosome 7 was correlated with venous involvement (P = 0.04). Ki 67 expression was significantly associated with hyperdiploid aberration of chromosome 17 (P = 0.01), but not with aberration of chromosome 3. There was a significant relationship between hyperdiploid aberration of chromosome 7 and Ki 67 expression (P = 0.01). In conclusions, gain of chromosome 17 may reflect tumour development, and aberration of chromosome 7 may affect metastatic potential of malignancy, whereas loss of chromosome 3 may be associated with early stage of tumour development in renal cell carcinoma.