[Survival analysis for localized renal cell carcinoma. Prognostic value of 1997 TNM classification]

The 5th edition of TNM classification for renal cell carcinoma changed the cut-off point of the tumor size for localized tumors, achieving a better distribution of patients with similar survival. Nevertheless, because of the variable evolution of renal cell carcinoma, the prognostic significance of tumor size is questioned as a staging criterion in organ-confined renal cell carcinoma. We analyse renal cell carcinoma specific survival and the prognostic significance of tumor size in I and II stage.

We made a retrospective study with 158 renal cell carcinoma surgically treated in our hospital along 12 years. It was created a data base with clinical variables from patient and tumor and analyzed pathological staging, nuclear grade and specific survival, overall stage I and II.

27 renal cell carcinoma were pT1 (17.08%), 52 pT2 (32.91%), 45 pT, (28.45%), 10 pT3B (6.32%), y 24 pT4 (15.18%). The specific survival at 5 years for pT1-pT2, I-II stage, was 100% and 94% respectively, and no statistic significant differences were found between stage I and II (log-rank test 0.53, p>0.05). The specific survival at 5 years for pT3a, pT3B, y pT4 was 76.5%, 66.6% y 38.4%. There was a significant difference in survival in accordance with the tumor location, intrarenal (T1 y T2) versus extrarenal (T3A, T3B, T4) (log-rank test 9.06, p< 0.05). According to nuclear grade we don't find significant differences for pT1 y pT2 (Fisher test, p=1). Regarding the relation between pT stage and nuclear grade of the tumor we obtained a chi-square inear tendency of 38.19, p<0.001.

The differences in the evolution of the organ-confined renal cell carcinoma with respect to the tumor size may be due to other molecular and biological variables, probably associated with stage, not controlled in essays. The TNM classification for organ-confined renal cell carcinoma based in tumor size seems artificial. New revisions of the classification system are necessary to identify which organ-confined carcinoma will have unfavourable evolution and to include them in a different category.