Login to Access Video or Poster Abstract: MP15-07
Sources of Funding: None

Introduction

Micropapillary urothelial carcinoma is a rare and aggressive histologic variant of bladder cancer. Treatment guidelines recommend forgoing bacillus Calmette-Guerin (BCG) therapy in favor of early radical cystectomy for non-muscle invasive micropapillary bladder cancer (NMI-MPBC) due to high rates of disease progression. We hypothesize that management of NMI-MPBC will vary across centers.

Methods

Patients with MPBC were identified from the National Cancer Database (2003-2013). Treatment trends and rates of pathological upstaging were identified. Bivariate and multivariate analyses were performed to assess differences in outcomes by treatment approach.

Results

777 patients were diagnosed with MPBC during the study period with 270 identified to have non-muscle invasive disease on presentation. BCG therapy was administered as initial therapy in 25.1% of NMI-MPBC patients and in 14.3% of non-micropapillary UC patients (p<0.001). _x000D_ _x000D_ Cystectomy was performed as primary therapy for NMI disease in 19.6% of MPBC and in 2.3% of non-micropapillary patients (p<0.001). Of the patients who underwent primary cystectomy, upstaging from NMI disease to T2-T4 disease was seen in 33.3% of the MPBC patients compared to 11.1% in patients with non-micropapillary disease (p<0.001). Upstaging to pathologic N1-3 disease was observed in 33.3% of MPBC patients compared to 11.1% non-micropapillary patients (p<0.001). _x000D_ _x000D_ Cystectomy as primary therapy for NMI-MPBC was more likely to be performed at academic (29.6%) compared to community cancer centers (11.3%) (p<0.001). On Cox regression analysis, adjusting for patient age, sex, race, comorbidities, and disease stage, care at academic cancer centers was associated with increased odds of having cystectomy as primary therapy compared to community cancer centers (OR = 3.11, 95% CI 1.53-6.29)._x000D_ _x000D_ Primary BCG therapy was not utilized any more frequently between academic (26.2%) and community cancer centers (23.7%) (p=0.64). _x000D_ _x000D_ _x000D_

Conclusions

The micropapillary variant of urothelial carcinoma is associated with increased odds of disease upstaging and node-positive disease. BCG is overutilized as primary treatment in this population. NMI-MPBC patients treated at academic centers were more likely to receive radical surgery as primary treatment compared to patients at community cancer centers. _x000D_

Funding

None