333 Background: Neoadjuvant chemotherapy (CT) is recommended prior to radical cystectomy (RC) in patients with muscle invasive urothelial carcinoma of the bladder (UCB), and has been shown to have modest survival benefit in clinical trials. The purpose of our study was to investigate the response and survival rates in patients with histologic variants (HV) and compare oncologic outcomes to patients with pure UCB. Methods: We performed a retrospective review of 163 patients treated with neoadjuvant CT prior to RC. Twenty-four patients with HV and 139 with pure UCB were identified. Numerous patient demographics, clinical and pathologic characteristics were evaluated including; clinical and pathologic stage, HV, lymphovascular invasion (LVI), margin status, node counts, concomitant carcinoma in situ (CIS), previous intravesical treatments, prior pelvic radiation, completeness of bladder tumor resection (TURBT), and CT regimens. Results: Patients with HV were younger (66.5 versus 71 years, p=0.04) but otherwise there were no significant differences noted between the two groups comparing previous treatments, clinical staging, margin status, node counts, CT regimens, # of neoadjuvant CT cycles, or rates of adjuvant CT administration. Of the 24 HV patients, 11 (47.8%) were downstaged to < pT2 compared to 50 (64.1%) of 139 patients with pure UCB (P=0.37). pT0 rates for HV and pure UCB were 16.7% and 23%, respectively (p=0.60). Twelve (50%) of the HV group compared to 65 (46.8%) of the pure UCB patients (p=0.83), had no evidence of disease at a mean follow up after RC of 19.5 (HV) and 22 (UCB) months. Eight (33.3%) patients with HV died of disease compared to 44 (31.7%) in the UCB group, (p=1.0). There was no significant difference noted in CSS and OS between the 2 groups, although there was a trend towards higher rates of node positive disease (p=0.086) and inferior CSS (p=0.09) in patients with HV compared to patients with pure UCB. Conclusions: Our results indicate that patients with HV experience similar oncologic outcomes from neoadjuvant systemic CT compared to patients with pure UCB.
PD33-12 SINGLE LYMPH NODE MALIGNANT INVOLVEMENT POST RADICAL CYSTECTOMY FOR UROTHELIAL CARCINOMA OF THE BLADDER: CLINICAL OUTCOMES AND PROGNOSTIC IMPLICATIONS
