High carbohydrate antigen 19-9 levels indicate poor prognosis in patients with bladder cancer following radical cystectomy.

Introduction: Our team previously reported that elevated carbohydrate antigen (CA) 19-9 levels are associated with a worse prognosis in upper tract urothelial carcinoma (UTUC). Several studies have reported a correlation between high tumor burden and elevated CA19-9 levels in urothelial carcinomas. However, no studies have specifically examined the association between CA19-9 levels and outcomes of patients with bladder cancer who underwent radical cystectomy. Therefore, we aimed to evaluate the relationship of CA19-9 levels in bladder cancer patients following radical cystectomy.

Materials And Methods: Among the 984 patients who underwent radical cystectomy at the Seoul National University Hospital between 1991 and 2022, 564 patients had available preoperative CA19-9 levels. The patients were divided into two groups: a low CA19-9 group (CA19-9 ≤ 37 U/mL) and high CA19-9 group (CA19-9 > 37 U/mL). Demographic parameters as well as preoperative and postoperative findings were compared between these two groups. Recurrence-free survival and overall survival were analyzed using multivariate Cox regression and Kaplan-Meier analyses.

Results: Sex distribution, age, body mass index, and underlying diseases (hypertension and diabetes mellitus) were similar between the two groups. The clinical T and N stages were significantly higher in the high CA19-9 group ( = 0.028 and = 0.019, respectively). The operative procedures, including open, laparoscopic, and robotic surgeries, were similarly performed in both groups. Pathologic T and N stages also tended to be higher in the high CA19-9 group ( < 0.001 and = 0.005, respectively). In the multivariate Cox regression analysis, the recurrence risk in the high CA19-9 group was significantly higher than that in the low group (HR 1.646; 95% CI 0.070-2.533, = 0.023). The 5-year recurrence-free survival rate was 53.5% and 35.5% in the low and high CA19-9 groups, respectively ( < 0.001). Overall survival tended to be worse in the high CA19-9 group; however, this difference was not statistically significant.

Conclusions: A high CA19-9 level is associated with a higher tumor burden in patients with bladder cancer. Furthermore, high CA19-9 levels are correlated to higher pathologic T and N stages after radical cystectomy and worse recurrence-free survival.