5075 Background: There is relatively little literature regarding the use of adjuvant chemotherapy following radical nephroureterectomy in the management of patients with upper tract urothelial carcinoma (UTUC). Our goal was to determine the incidence of receipt of adjuvant chemotherapy in high-risk patients and the ensuing effect on overall- and cancer-specific survival. Methods: Using an international collaborative database, we identified 1390 patients who underwent nephroureterectomy for non-metastatic UTUC between the years of 1992 and 2006. Of these, 542 (39%) patients were classified as high-risk (pT3N0, pT4N0, and/or lymph node positive). These patients were separated into two groups—those who did and did not receive adjuvant chemotherapy—and were stratified by gender, age group, performance status, tumor grade and stage. Cox proportional hazard modeling and Kaplan-Meier analyses were used to determine overall- and cancer-specific survival amongst the cohorts. Results: Of the high-risk patients, 121 (22%) received adjuvant chemotherapy. Adjuvant chemotherapy was more commonly administered in the context of increased tumor grade and stage (p < 0.001). Median survival in the entire cohort was 24 months (range 0–231 months). There was no significant difference in overall- or cancer-specific survival between those who did and did not receive adjuvant chemotherapy; however age, performance status, tumor grade, and tumor stage were significant predictors of both overall and cancer-specific survival. Conclusions: Adjuvant chemotherapy is infrequently utilized in the treatment of patients with high-risk UTUC after nephroureterectomy. Despite this, it appears that adjuvant chemotherapy confers minimal impact on overall- or cancer-specific survival in this group. No significant financial relationships to disclose.