1062 PRESENCE OF CIRCULATING TUMOUR CELLS IN NON-METASTATIC BLADDER CANCER IS AN INDEPENDENT RISK FACTOR FOR WORSE OUTCOME

INTRODUCTION AND OBJECTIVES: Circulating tumour cells (CTC) are detectable in patients with clinical non-metastatic urothelial carcinoma of the bladder (NMUCB). To prospectively further evaluate the biological significance of CTC in NMUCB patients and to elucidate clinical implications. METHODS: Between July 2007 and September 2010 blood samples of 111 consecutive, localized bladder cancer patients scheduled for cystectomy were prospectively investigated for CTCs. Blood (7.5 ml) was collected in CellSave tubes (Veridex) and analyzed for CTC using the CellSearch Epithelial Cell Kit (Veridex). Data were compared with clinicopathological findings. Progression-free, cancerspecific and overall survival were correlated with CTC findings. Uniand multivariable Cox regression analysis was performed to identify risk factors for disease progression and cancer-specific death. RESULTS: All blood samples were available for evaluation. Preoperative staging revealed metastatic disease in 11 patients. These were excluded from analyses. Overall, in 27 of the remaining 100 NMUCB patients (27%) CTC were detectable. Mean number of CTCs was 6.0 18.9 (range:1–100; median:2). Presence of CTC was not associated with locally advanced disease or lymph node infiltration. A median follow up of 16 months was available for 70 patients (70%). Patients with preoperative proof of CTC showed significantly worse progression-free (p 0.001), cancer-specific (p 0.001) and overall survival (p 0.001) compared to CTC-negative patients. Progression and survival were not influenced by the number of detected CTC (progression: 1 CTC vs. 2 CTC p 0.8; survival: 1 CTC vs. 2 CTC p 0.5). Multivariable Cox regression analysis confirmed CTC-status as an independent risk factor for disease progression and cancer related death. CONCLUSIONS: Our findings confirm that CTC are detectable in up to one third of all patients with clinical NMUCB. Furthermore, proof of CTC at time of radical cystectomy is associated with a worse survival. Therefore, CTC detection might be beneficial as an indicator for further adjuvant therapies.