Restaging of the Stage T1 Localized Renal Cell Carcinomas Using New Cut-off Value

Kim, Dong Il; Park, Choal Hee; Kim, Chun Il

Abstract

PURPOSE: New cutoffs have recently been proposed for restaging T1 diseases, as the prognostic differences were more prominent with these cutoffs. The validity of these cutoffs was evaluated by restaging patients with localized renal cell carcinomas (T1-2N0M0) using the new cutoffs (2.5, 3, 4, 5, 7 and 10cm, and capsule invasion).
MATERIALS AND METHODS
99 patients with pathologically confirmed T1 and T2 carcinomas, who had undergone radical nephrectomy between June 1990 and March 2003, were retrospectively reviewed. The study group comprised of 61 men and 38 women, with a mean age of 56.2, ranging from 21 to 78 years. The mean follow up length was 69, ranging from 8 to 162 months. The patients were divided into two groups using the new cutoff points (2.5, 3, 4, 5, 7 and 10cm, and capsule invasion). The survival curves were calculated by the Kaplan-Meier method for each cutoff point, with Log-rank tests used to compare the values of the new cutoff points.
RESULTS
Statistically significant cancer specific survivals at 4, 5 and 7cm cutoffs, with a 5cm cutoff point, were used to maximize the differences in the cancer specific survivals. The 4cm cutoff point was the only statistically significant cutoff value for disease free survivals. Capsule invasion was not a statistically significant cutoff value.
CONCLUSIONS
A 5cm cutoff point was proposed to divide the T1N0M0 classification into T1a and T1b subclasses. Patients with localized renal cell carcinomas larger than 4cm in size were considered for radical nephrectomy rather than a partial nephrectomy in relation to a local recurrence.