A Study of Lipid- and Protein- Bound Sialic Acids for the Diagnosis of Bladder Cancer and Their Relationships with the Severity of Malignancy

Background: The gold standard for detection of bladder cancer is cystoscopy, which is an invasive and complicated procedure. Our study was conducted to find a tumor marker with high specificity, sensitivity, and accuracy for the diagnosis of bladder cancer. Methods: Serum samples were collected from ۵۸ bladder cancer patients and ۶۰ healthy control subjects. Levels of lipid-bound sialic acid (LBSA), and protein-bound sialic acid (PBSA) were measured spectrophotometrically by Aminoff’s method. Results: Mean levels of both markers were found to be significantly higher in the patients than the healthy controls. Positive correlations were observed between serum levels of lipid- (r=۰.۲۸۳, p<۰.۰۵) and protein- bound (r=۰.۵۶, p<۰.۰۵) sialic acids and the grade of malignancy. To differentiate patients with bladder tumors from healthy controls, cut-offpoints were determined for each of the two parameters based on Receiver Operating Characteristic (ROC) curve analysis (LBSA=۲۱.۲۵ mg/dL, PBSA=۶.۱۵ mg/dL). The data showed good sensitivities (LBSA=۸۹%, PBSA=۷۹%), specificities (LBSA=۷۰%, PBSA=۷۰%) and accuracies (LBSA=۸۳%, PBSA=۸۱%) for both markers. Conclusion: Measuring serum LBSA and PBSA by this simple, reproducible, noninvasive, and inexpensive method can accurately discriminate cancer patients from healthy individuals.

کلیدواژه ها:

N-Acetylneuraminic Acid ، Tumor Markers ، Urinary Bladder Neoplasms