Prevalence of atypical urine cytology in patients treated with gemcitabine-cisplatin (GC) for urothelial carcinoma (UC).

Abstract

363 Background: The prevalence of atypical urothelial cells (AUC) in the general population is estimated to range between 2-23% with known variability between individual pathologists’ use of this diagnosis. At our institution, the AUC rate for all urinary tract cytology (UTC) is 6.1%. Increased rates of urothelial atypia have been described in pts receiving certain systemic and intravesical therapies for UC. This may confound the use of UTC for post-therapy surveillance. Our objective is to describe the prevalence of urothelial atypia in pts treated with GC, as it is currently unknown. Methods: Patients who received at least one cycle of GC for UC at a single institution from 1/1/2007-9/30/2014 were identified. Demographics, clinical characteristics, treatment setting, number of cycles, and specimen type were recorded. Urine cytology reports were reviewed and tabulated. Results: Seventy-four pts treated with GC were identified. Median age at treatment was 65 (range 42-80); 58 (78%) were male. Median number of cycles was 4 (range 1-9). Treatment settings were: 15 (20%) neoadjuvant, 38 (51%) adjuvant, and 21 (28%) metastatic. Ten (14%) pts were previously treated with intravesical therapy (9 BCG, 1 mitomycin). Thirty-six (49%) pts had urine cytology available. Twenty-seven (75%) pts had at least 1 urine cytology within 12 months post-chemotherapy, with 44 total specimens. Nine (25%) pts had cytology performed >1-year post treatment. Cytology specimens within 12 months post-chemotherapy were reviewed. Two out of 44 specimens had AUC (5%), with all other cases negative. The pts with AUC were male, received adjuvant therapy, had prior radical cystectomy with orthotopic neobladder reconstruction, and had no intravesical therapy. Conclusions: The prevalence of AUC in pts treated with GC was similar to the general population. Chemotherapy with GC does not appear to morphologically affect urothelial cells. If atypical UTC is seen in this population, the cause should be investigated, as GC does not appear to influence urothelial changes. Additional study is needed to characterize the impact of systemic therapy on urothelial atypia and to guide the use of urine cytology for post-therapy surveillance.