Prognostic Impact of Preoperative Thrombocytosis on Recurrence-Free Survival in Patients with Upper Tract Urothelial Carcinoma

Background The aim of this work was to evaluate the prognostic potential of preoperative thrombocytosis for recurrence-free survival (RFS) and cancer-specific survival (CSS) among patients subjected to radical nephroureterectomy (RNU) due to UTUC. Patients and Methods Analytical cohort was composed of a single-center series of 405 patients treated between January 1999 and December 2020. Thrombocytosis was defined as a platelet count exceeding the threshold value of 400 × 10 9 per L. Along with the Kaplan–Meier survival probability, Cox proportional hazard regression models were used. Results Preoperative thrombocytosis confirmed in 71 patients (17.5%) was significantly associated with the higher pathological tumor stage, lymph node metastasis, prior bladder cancer diagnosis, and preoperative anemia. With a median post-surgical follow-up period of 33.5 months, 125 patients (30.9%) experienced disease recurrence. The recurrence rate among patients with normal platelet levels was 13.6%, compared with 22.2% in those with preoperative thrombocytosis ( p < 0.03). The 5-year RFS estimates reached 36.6% in the thrombocytosis-confirmed group. Multivariate analysis implied that preoperative thrombocytosis was a significant independent prognosticator of both poor RFS (HR 2.22, 95% CI 1.14–4.31, p = 0.02) and CSS (HR 2.48, 95% CI 1.14–3.09, p = 0.01). Conclusions Patients with a clinically significant elevation of platelet count prior to RNU were more likely to have UTUC with advanced tumor stages and lymph node metastases. Preoperative thrombocytosis was an independent predictor of RFS and CSS in patients who underwent radical nephroureterectomy. Furthermore, preoperative thrombocytosis may complement and refine UTUC clinical prediction algorithms as an independent indicator of adverse survival outcomes.