[Changes in the concentration of N-acetylneuraminic acid in the blood of patients with bladder cancer during radiotherapy].

The N-acetylneuraminic acid (N-ANA) concentration of serum in 24 patients with bladder carcinoma was measured with a modified Arzneibuch (D.L.) GDR-method before, during and after the postoperative radiotherapy. It was found that the N-ANA-concentrations in the patients operated resulted in a dependence from tumor staging already before the radiotherapy. The N-ANA concentration rose with increased staging. A temporary enhancement of the N-ANA-concentration with the maximum between 20. and 25 radiation fractions occurred in patients of staging T3 and relapses as well as with tumor cells being only little differentiated. The results are discussed in relation to the clinical importance.