[Evaluation of pT3a stage in the current classification for renal cancer].

Objective: We assessed the prognostic value of a stage pT3a diagnosis based on perirrenal fat infiltration.
Material and Methods: A series of 300 patients diagnosed of renal cell carcinoma (CCR) between 1992 and 2001 were retrospectively analyzed. Focusing on pT3a tumors as defined by perirrenal fat infiltration, a group of 92 patients (91,08%) regardless lymph node involvement (Nall) were included. Patients with distant metastases were excluded. In patients with pT3a Nall M0 tumors, tumour size was a significant parameter predicting survival. The most significant cut-off value for tumor size based on ROC curve was 5,5 cm. Therefore two groups were defined (up to 5,5 cm or greater than 5,5 cm) and actuarial survival were compared between both groups.
Results: No significant differences were found comparing actuarial survival of selected pT3a and tumour size less than 5,5 cm with pT1 and pT2 tumors. After classifying selected pT3a less than 5,5 cm as pT1, multivariate analysis showed no differences regarding to prognostic variables before and after classification. Subsequently multivariate analysis showed that modified T stage was an independent significant predictor of cancer specific actuarial survival.
Conclusions: Perirrenal fat infiltration in renal cell carcinoma should not be used to assign T category. In our series grading tumors pT3a lesser than 5,5 cm as pT1/pT2 TNM stage does not affect their prognostic value.