Gemcitabine vs Water Irrigation for Urothelial Cancer

Inclusion Criteria: * Biopsy proven UTUC with plan for excisional surgery (distal ureterectomy or nephroureterectomy) with curative intent * Age 18 - 90 years * Life expectancy \> 1 year * Women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry, for the duration of study participation, and for 90 days following completion of therapy. Should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately. * A female of child-bearing potential is any woman (regardless of sexual orientation, having undergone a tubal ligation, or remaining celibate by choice) who meets the following criteria: * Has not undergone a hysterectomy or bilateral oophorectomy; or * Has not been naturally postmenopausal for at least 12 consecutive months (i.e., has had menses at any time in the preceding 12 consecutive months). * Ability to understand and the willingness to sign a written informed consent. Exclusion Criteria: * Concurrent or prior diagnosis of bladder cancer with a disease-free interval of less than three years. * Synchronous bilateral upper tract urothelial carcinoma (prior history of contralateral UTUC is permissible with a disease-free interval of more than three years). * Plan for radical cystectomy. * Small bladder capacity (\< 100 mL). * History of allergic reactions attributed to compounds of similar chemical or biologic composition to gemcitabine or other agents used in study.