Background: Conventional pathologic classifications of human renal cell carcinoma (RCC) give little insight into oncogenesis and little assistance in predicting the clinical behavior of this disease. Identification of specific genetic alterations involved in the development of RCC using fluorescence in situ hybridization (FISH) however, may help provide foundations for classification, prognosis, and clinical management of the patients.
Methods: Archival, paraffin embedded tissue sections from 30 human non-papillary RCCs were examined with a dual color FISH technique for loss of chromosomes 3p and 14q. Telomeric DNA probes from 3p or 14q and an internal ploidy control probe, centromeric probe of chromosome 2, were applied directly to the tumor sections. The correlations between loss of 3p or 14q, and tumor ploidy, with tumor grade, pathologic stage, and patient outcome were assessed.
Results: Ninety percent of the patients (27) lost chromosome 3p, and 36.7% of the patients (11) had chromosome 14q deletions. The loss of 3p in the samples tested was unrelated to patient age, gender, outcome, tumor stage, or histologic grade. However, the deletion of 14q was significantly correlated with higher stage (P = 0.01), histologic grade (P = 0.01), and patient outcome (P < 10(-4)).
Conclusion: The close correlation of 14q loss with higher stage, higher histologic grade, and poorer outcome for patients with nonpapillary RCC indicates that it may be a promising prognostic marker.