Objective: The Association Française d 'Urologie conducted a national epidemiological study in 1997. Using our database, we compared our results, up-dated the epidemiological data and evaluated the differences observed over a period of 15 years.
Patients and methods: 844 patients operated for kidney tumour between 1985 and 2000 were analysed and 810 were included in this study. Survival analysis was performed according to the Kaplan-Meier method. Relative risks were determined by the Log-Rank test and multivariate analysis was performed with the Cox regression model. The limit of significance was 0.05.
Results: The mean age at the time of diagnosis was 59.6 years (range: 14.6-90.2). Most tumours were discovered incidentally by ultrasound. The mean tumour diameter was 61.7 mm (range: 20-230). The most frequent surgical operation was radical nephrectomy, but there was a tendency towards an increasing number of conservative operations. Histology revealed 94% of renal cell carcinomas, with 73% of conventional cell carcinomas. The mean follow-up was 49 months (range: 0-197) and 5-year and 10-year survival rates were 74.9 months and 62.6 months, respectively. Multivariate statistical analysis confirmed the prognostic significance of N and M stage, Fuhrman grade, histological type, as well as renal capsule invasion.
Conclusion: Our data largely confirm those of the last national study conducted in 1997 as well as those of the international literature. Kidney tumours are increasingly discovered incidentally, but tumour size and the age of patients remain stable, while the number of conservative procedures continues to increase each year In addition to the usual prognostic factors, we found that renal capsule invasion was an independent prognostic factor.