[PREDICTIVE AND PROGNOSTIC SIGNIFICANCE OF PRE-TREATMENT LYMPHOCYTE COUNT IN PATIENTS WITH METASTATIC UROTHELIAL CARCINOMA TREATED WITH PLATINUM-BASED FIRST-LINE CHEMOTHERAPY].

(Purpose) Pre-treatment low lymphocyte count may result from cytokine secretion by the tumor microenvironment, in association with aggressive tumor biology. We sought to establish the prognostic impact of the absolute lymphocyte count (ALC) in advanced urothelial carcinoma. (Patients and method) We retrospectively reviewed 63 patients with unresectable or metastatic urothelial carcinoma who were treated with platinum-based first-line systemic chemotherapy between January 2011 and April 2018. We evaluated the importance of the ALC in patients who underwent systematic chemotherapy. (Results) Thirty-eight patients (60%) died from urothelial carcinoma, with a median follow-up interval of 12.2 months. The median overall survival (OS) duration was 15.3 months. The mean ALC in the stable and progressive disease group was lower than that in the complete and partial response group (1,312 /μL and 1,666 /μL, respectively, p=0.004). The ALC of 1,460 /μL was determined as the cut-off on Receiver operating characteristic curve analysis. The log-rank test revealed that the lymphocytopenia group (ALC <1,460 /μL) showed significantly poorer prognoses than the non-lymphocytopenia group (p=0.001). Multivariate analyses showed that lymphocytopenia was an independent poor prognostic factor (hazard ratios of 3.46, p=0.002). (Conclusions) Pre-treatment low lymphocyte count is an independent poor prognostic factor in patients with urothelial carcinoma who underwent platinum-based first-line systemic chemotherapy.