Prognostic impact of serum cytokeratin 19 fragments in patient with metastatic urothelial cancer (mUC) treated with first-line chemotherapy.

Abstract

473 Background: Even today, when several immune checkpoint Inhibitors have been approved for the treatment of metastatic urothelial cancer (mUC), cytotoxic chemotherapy (CTC) still remains the mainstay for first-line treatment. We believe that the prognostic factors for the first-line CTC have become more important again and need to be re-analyzed. Current guidelines do not yet provide recommendations for any serum tumor markers in patients with mUC. Previous studies have shown that serum cytokeratin 19 fragments levels (sCK) were correlated with depth of tumor invasion and metastatic burden in patients with bladder cancer. In this study we evaluated whether sCK, and other clinical parameters could predict overall survival (OS) in patients with mUC treated with CTC. Methods: Two hundreds fifty two patients with mUC received CTC from December 2006 to 2016 at our institution. sCK had been measured in 128 patients at diagnosis of mUC. OS rate were analyzed by Kaplan–Meier curves and log–rank test. Multivariate analysis was carried out using the Cox hazards model. Tumor burden (TB) was measured based on Response Evaluation Criteria In Solid Tumor (version 1.1). Results: Of 128 patients, with median age of 72 (44-93), 36 (28%) had lung metastasis, 11 (9%) had bone metastasis, 10 (8%) had liver metastasis (LM). Ninety five (74%) patients received platinum based chemotherapy as a first-line treatment. During the median follow-up period of 19 (1-89) months, 72 patients (70%) had died. A 1-year (1y) OS was 51% and a 2y-OS was 36%. On univariate analysis, performance status (PS) (HR2.0, p<0.005), sCK (HR3.9, p<0.001), CRP (HR4.0, p<0.001), neutrophil-lymphocyte ratio (HR1.9, p<0.049), LM (HR2.0, p=0.042) and TB (HR2.4, p<0.001) were the significant prognostic factors for OS. On multivariate analysis, PS (HR2.0, 95%CI (1.05-3.85) p=0.036 ), sCK (HR3.1, 95%CI (1.3-8.3), p=0.011), and LM (HR3.0, 95%CI (1.06-6.98), p=0.022) were the independent prognostic factors for OS. Based on these 3 factors we divided patients into three groups, good risk (G, 0 factor), intermediate risk (I, 1 factor) and poor risk (P, 2-3 factors). There was a significant difference between the three groups. (G vs I: p<0.001, I vs P: p=0.001). Conclusions: PS, sCK, and LM were the independent prognostic factors for OS in patients with mUC receiving CTC. For the patients in good or intermediate risk with this score, early exposure of ICIs should be performed after CTCs. Treatment strategy should be changed in patients with poor risk since CTC is primary refractory in such population.