Analysis of renal cell carcinoma with subdiaphragmatic macroscopic venous invasion (T3b).

OBJECTIVE: To review our institutional experience of surgery for renal cell carcinoma (RCC) with subdiaphragmatic macroscopic venous invasion (T3b) and to assess variables associated with cancer-specific survival (CSS), as the stratification of RCC with venous involvement (T3b and T3c) is subject to debate. PATIENTS AND METHODS: We retrospectively reviewed the hospital records of patients who underwent a radical nephrectomy with resection of subdiaphragmatic tumour thrombus (T T) between October 1990 and May 2006. The log-rank and Cox uni- and multivariate regression analysis were used to evaluate predictive factors for CSS.
RESULTS: In all, 101 cases were identified. In the N0M0 group, univariate Cox regression analysis confirmed that ipsilateral adrenal gland invasion, Mayo Clinic level of T T, histological subtype and fat invasion were significantly associated with worse CSS. In multivariate Cox regression analysis, only Mayo Clinic level of T T was an independent predictor for CSS. In the subgroup with renal vein involvement only, the median CSS was not reached. In the subgroups with level I, II and III T T involvement, the median CSS was 69, 26 and 21 months, respectively. In the N+ and/or M+ group, only tumour size and type were independent predictors of CSS, while the level of T T was not. Radical nephrectomy yielded poor results with a median CSS of 13 months.
CONCLUSION: The Mayo Clinic level of T T is an independent prognostic predictor for CSS in non-metastatic T3b RCC. We strongly support the need for re-classification of the currently applied 2002 Tumour-Node-Metastasis staging system, which in its present form does not discriminate between levels of subdiaphragmatic venous invasion.