Objective: Annual national epidemiological evaluation of renal tumours by means of a multicentre survey proposed by the oncology committee of the Association Française d'Urologie.
Patients and methods: From April 1, 1993 to March 31, 1994, 970 patients were recruited by 54 centres. A computer form was completed for each patient, including: the patient's age and sex, modalities of discovery of the tumour, complementary investigations (radiological and laboratory tests) performed, treatment performed, TNM staging, histological characteristics of the tumour.
Results: The mean age of the patients was 62.1 years with a sex ratio of 2 males to 1 female. The rate of incidental tumours was 40%. Radical nephrectomy was performed in 90% of cases and conservative surgery was performed in 7% of cases. Medical treatment was instituted in 5% of cases. The distribution of tumours by TNM stage was: pT1: 8%, pT2: 53%, pT3a: 21% and pT3b: 18%. Lymph node involvement was detected in 12% of cases, and visceral metastases were identified in 6% of cases. 80% of incidental tumours were intracapsular. The predominant histological type was renal cell carcinoma (66%). The mean tumour size for the entire series of tumours was 6.4 +/- 3.5 cm and was significantly larger in symptomatic patients and in those with poor prognostic factors (adrenal involvement, inferior vena cava invasion, lymph node and/or visceral involvement). Adrenal and inferior vena cava involvement was detected in 4% of cases. 14% of patients had multifocal tumours, which was not correlated with either the size of the tumour or the cell type. The nuclear grade was determined in 66% of cases and was significantly correlated with perirenal fat and lymph node involvement.
Conclusion: This survey collected approximately 1/5 of all new annual cases of renal cell carcinoma in France and therefore provided a precise evaluation of the current epidemiology of this tumour.