Cytokeratins as useful serum markers in the diagnosis and monitoring of Egyptian bladder cancer. A comparative study between TPA and TPS

ABSTRACT

Cytokeratins [CKs] have been shown to he over expressed in bladder cancer and to be valuable as tumor markers in urology. The present study was designed to evaluate the diagnostic value of Tissue Polypeptide Antigen [TPA] and tissue Polypeptide Specific Antigen [TPS], as serum markers exploring some specific CKS, in the diagnosis and monitoring of bladder cancer. For this purpose, a cohort of 174 case were allocated into three groups; group 1 included 64 histologically confirmed primary bladder cancer patients scheduled for different treatment modalities, group 2 comprised 75 cases with benign urologic conditions and group 3 were 35 healthy volunteers. Serum TPA and TPS were estimated in all cases after initial evaluation as well as postoperatively in group 1 using an Enzyme Limbed Immuno Sorbant Assay[ELISA] technique. Results showed that serum TPA and TPS levels were significantly higher in group 1 as compared to the other groups, P<0.01. Evaluation by histologic findings declared a higher sensitivity of TPA [55.7%] at a specificity 95% in transitional cell carcinoma [TCC] as compared to 39% for TPS. A high percentage of Egyptian bladder cancer [+30%] is represented by- squamous cell carcinoma [SCC]; in this population TPS showed the highest sensitivity reaching up to 66% followed by TPA [48%]. The sensitivity of either marker increased with advancing tumor stage and grade in all histologic types as well as with nodal stage and metastases, p< 0.01. In all treated malignant conditions there was no statistically significant difference between serum TPA and TPS levels in free disease states. Cases showing tumor relapse exhibited a steady rise in both serum TPA and TPS levels before any detectable clinical recurrence with no statistically significant difference between either marker. In conclusion, serum levels of TPA and TPS in bladder cancer patients correlated well with initial tumor stage and grade and served for detecting and monitoring tumor relapse