[Clinicopathological characteristics of small size renal cell carcinoma].

BACKGROUND

We tried to identify which size or less means small size in renal cell carcinoma (RCC) associated with prognosis including Robson's stage 1.

METHODS

We classified RCC based upon the tumour size into cases with 2.5 cm or less (NO, VO, MO: group I: n = 27, cause-specific cases = 26) and cases with 2.6 to 3.0 cm (NO, VO, MO: group II: n = 31, cause-specific cases = 27). Based upon this classification, we studied on the clinical features of small size RCC.

RESULTS

(1) Regarding the clinical features including mean age, sex ratio, affected side, opportunity of diagnosis, diagnostic approach and preoperative laboratory findings, no specific difference was observed between groups I and II except for the localization of tumour in the kidney (a significantly high rate was observed in the mid portion of the tumour in group I compared with that in group II). 2) The mean size of group I was 1.98 cm (0.7 to 2.5 cm), and that of group II was 2.84 cm (2.6 to 3.0 cm). On the other hand, the mean size of Robson's stage 1 was 5.5 cm (0.7 to 18.0 cm). Therefore, the tumour size of Robson's stage 1 was significantly larger than that of groups I and II (p < 0.001). 3) The survival rate of group I showed worse trend than that of group II after 12 years postoperatively, but no significant difference was observed between these 2 groups. Furthermore, the survival rate of Robson's stage 1 showed better trend than that of the tumour size with 3.0 cm or less, but no significant difference was observed between these 2 groups. 4) As to the grade in each group, no significant difference of survival was observed. 5) As to the recurrent rate in each group, it was 19.2% in group I, 7.4% in group II and 18.5% in Robson's stage 1. Therefore, no significant difference of recurrent rate was observed in these groups.

CONCLUSION

It is difficult to identify which size or less means small size RCC associated with prognosis. This is because no specific clinical feature was observed in these small size cases compared with Robson's stage 1 which consisted with larger size tumour.