Abstract
We evaluated serum levels of soluble fragments of cytokeratin 19 (CYFRA 21‐1) by immunoassay (ES‐700; Roche Diagnostics, Mannheim, Germany) to assess its usefulness in the diagnosis and follow‐up of bladder cancer. The study included 39 patients with a diagnosis of transitional cell carcinoma (group 1) and 190 patients (group 2) with no evidence of tumor. In group 2, 180 patients had a history of bladder cancer, and 10 had benign prostatic hyperplasia. Significant differences in CYFRA 21‐1 concentrations between groups 1 and 2 (P<0.01) were noted. However, CYFRA 21‐1 levels did not significantly differ between the patients with benign prostatic hyperplasia and those with bladder cancer (P=0.274). CYFRA 21‐1 values were higher in invasive bladder cancer compared to that detected in superficial stages (P=0.011). Setting the optimal cutoff value at 2.5 ng/mL resulted in a sensitivity of 43.6% and a specificity of 82.1%. No statistical differences were found when we compared disease‐free time among the 66 patients with recurrences (30.7 months with levels <2.5 ng/mL vs. 41.2 months with levels >2.5 ng/mL; P=0.248). The risk of recurrence in patients with levels lower than 2.5 ng/mL (0.79) was no different (P=0.097) from that found in patients with higher levels (1.69). CYFRA 21‐1 serum levels do not provide enough sensitivity to justify its application in routine protocols for the detection and follow‐up of bladder cancer. J. Clin. Lab. Anal. 19:167–171, 2005. © 2005 Wiley‐Liss, Inc.