Relationship between age at diagnosis and clinicopathologic features of renal cell carcinoma.

Objectives: To analyse the influence of age at diagnosis on tumour characteristics and cancer-specific survival in renal cell carcinoma (RCC).
Methods: Data on age, tumour characteristics, and survival for 4774 patients from 12 European RCC databases were recorded. Patients were divided into four groups according to age at diagnosis: < or =40, >40 and <60, > or =60 and <80, and > or =80 yr. The following variables were analysed: TNM stage, Fuhrman grade, tumour size, symptoms at diagnosis, ECOG performance status (PS), and cancer-specific survival. The groups were compared for usual clinical and pathologic variables, and cancer-specific survival.
Results: The four groups accounted for 288 (6%), 1839 (38.5%), 2499 (52.3%), and 148 cases (3.2%), respectively. Differences were found among groups for tumour stage, symptoms at diagnosis, ECOG PS, Fuhrman grade (p<0.001), tumour size, M stage, and histologic subtype (p: 0.02). Patients < or =40 yr were more likely to have papillary or chromophobe RCCs and less likely to have clear-cell RCCs. No significant difference was found among groups for N stage (p: 0.15). The 5-yr cancer-specific survival rates for the four age categories were 85%, 74%, 70%, and 69%, respectively. In multivariate analysis age category remained an independent prognostic parameter (p<0.001).
Conclusions: Renal tumours diagnosed in younger age are characterized by lower tumour stages and grades as well as favourable histologic patterns compared with tumours in older patients. Basic research is required for explaining such a relationship between age, tumour aggressiveness, and therefore tumour biology.