Active surveillance for renal cortical neoplasms.

PURPOSE We retrospectively evaluated our single center experience with patients with renal cortical neoplasms who elected active surveillance. MATERIALS AND METHODS We retrospectively evaluated our urological oncology database between January 1993 and January 2009, identifying a total of 223 renal cortical neoplasms in 212 patients that were initially managed by active surveillance. We described patient and tumor characteristics, and assessed the differences between patients who remained on AS and those who underwent delayed intervention or progressed with metastasis. RESULTS Median patient age was 71 years at active surveillance initiation and the median Charlson comorbidity index was 3. Median tumor size was 2.8 cm (range 0.5 to 13.7) at study enrollment and 3.7 cm (range 0.9 to 14.1) at final assessment. The median growth rate in the entire cohort was 0.34 cm per year (range 0.29 to 2.3). Median followup was 35 months (range 6 to 137). Active surveillance failed in 15 patients (7%), of whom 4 (2%) progressed to metastasis and 11 (5%) required intervention. When comparing cases of failed active surveillance with those that continued, there were statistical differences in initial tumor size (2.61 vs 3.64 cm, p = 0.019), final tumor size (3.56 vs 5.17 cm, p = 0.001) and growth rate (0.34 vs 1.75, p = 0.001). There was no correlation between initial tumor size and growth rate (Pearson's coefficient r = 0.006, p = 0.932). A total of 14 patients died of another medical condition. Only 1 cancer related death (0.5%) was reported in the entire cohort. CONCLUSIONS Active surveillance for renal cortical neoplasms in select older patients with comorbidities is a reasonable treatment option. At 3-year followup we noted a 7% failure rate.