[Renal cell carcinoma before the age of 40: prognostic factors].

Objective: To study the prognostic value of tumour diameter, TNM stage, Führman's nuclear grade and CD44 adhesion molecule expression in renal cell carcinoma (RCC) before the age of 40 years.

Material And Methods: Nineteen patients under the age of 40 (12 males and 7 females; mean age 30.8 years), undergoing total nephrectomy for RCC were included in this study. Tumour diameter, TNM 1997 stage, and Führman's nuclear grade were defined for each tumour. Standard CD44 adhesion molecule (CD44H) expression was evaluated semiquantitatively by immunohistochemistry on each tumour. The prognostic value of the various variables was determined by Mann-Whitney and Chi-square tests and survival analysis was performed by the Kaplan-Meier method.

Results: Six patients (31.5%) died from their cancer with a mean follow-up of 81.4 months. Mean tumour diameter was 9 +/- 4.5 cm. Tumours were Führman I/II in 4 cases, Führman III/IV in 15 cases, T1/T2 in 14 cases and T3/T4 in 5 cases. CD44H expression was high (> or = 20%) in 9 cases (47.3%). The prognostic factors identified in this study were: tumour stage (p = 0.01), grade (p = 0.04), venous extension (p = 0.001) and CD44H overexpression (p = 0.003).

Conclusion: Prognostic factors of renal cancer in patients under the age of 40 years do not appear to be different from those of older patients. The prognostic factors identified in this study must be validated by multicentre studies based on larger populations.