A new prognostic model for cancer-specific survival after radical cystectomy including pretreatment thrombocytosis and standard pathological risk factors

OBJECTIVE To investigate the oncological significance of preoperative thrombocytosis in patients with invasive bladder cancer undergoing radical cystectomy, as it has been reported as a marker for aggressive tumour biology in a variety of solid tumours. PATIENTS AND METHODS The series comprised 258 patients undergoing radical cystectomy between 1999 and 2010 in whom different clinical and histopathological parameters were assessed. Elevated platelet count was defined as >450 x 10(9)/L. Based on regression estimates of significant parameters in multivariable analysis a new weighted scoring model was developed to predict cancer-specific outcomes. RESULTS The median follow-up was 30 months (6-116). Of the 258 patients, 26 (10.1%) had elevated and 232 (89.9%) had normal platelet count. The 3-year cancer-specific survival in patients with normal and elevated platelet count was 61.5% and 32.7%, respectively (P < 0.001). In multivariable analysis, cancer-specific survival was significantly lower in patients with locally advanced disease (>= pT3a) (relative risk 2.91, 1.54-5.65; P = 0.001), positive soft tissue surgical margins (4.03, 1.99-7.92; P = 0.001) and thrombocytosis (2.68, 1.26-5.14; P = 0.011). The 3-year cancer-specific survival in patients with a score 0 (low risk), 1-2 (intermediate risk) and 3-5 (high risk) was 81.0%, 54.8% and 8.2%, respectively (P < 0.001). Consideration of preoperative platelet count in the final model increased its predictive accuracy by 1.8% with a concordance index of 0.745 (P = 0.040). CONCLUSIONS The presence of thrombocytosis at radical cystectomy portends unfavourable prognosis. We constructed a simple weighted prognostic model for cancer-specific outcomes after radical cystectomy based on pretreatment platelet count and established pathological risk factors. These data warrant external validation and may allow for tailored monitoring and selection of appropriate patients for neoadjuvant and adjuvant trials.