Prognostic significance of tumour size in patients after tumour nephrectomy for localised renal cell carcinoma.

Abstract

Staging of the primary tumour is accepted as the most important prognostic factor in organ confined renal cell carcinoma. The outcome of 286 patients with non-metastatic RCC treated by radical nephrectomy at our institution between 1968 and 1992 was evaluated retrospectively. The median follow-up was 114 +/- 62.6 months. In T1/T2 tumours, the validity of tumour size cut-off points for predicting survival outcome was tested. According to the 1997 TNM classification, 168 patients (59%) showed pathological stage T1 (72 stage T1a, 96 stage T1b), 30 (10%) showed stage T2, 84 patients (29%) demonstrated T3 tumours (53 stage T3a, 31 stage T3b), and 4 patients (2%) presented with T4 tumours. The median survival estimated by Kaplan-Meier analysis for T1a, T1b, T2, T3a, T3b and T4 tumours was over 300 months, 187.0 +/- 32.76; 177.0 +/- 1.21; 121.0 +/- 2.57; 124.0 +/- 11.82 and 52.0 +/- 18.38 months, respectively. Regarding survival in T1/T2 tumours Cox regression analysis yielded the highest significance level for a tumour size cut-off point at 4 cm (p = 0.003; 95%CI 1.511-6.991), but no prognostic value for a cut-off point at 7 cm (T1 vs. T2) (p = 0.375; 95%CI 0.655-3.071). Tumour size is an important prognostic factor in patients with organ confined RCC. The recently specified new cut-off point of 4 cm for T1a/T1b tumours is feasible for separating groups with different survival after tumour nephrectomy and should be considered as the new boundary between T1 and T2 stages. Hence, a more accurate prediction of prognostic differences between these groups should be possible.