[Determination of urinary CA19-9 levels in urothelial cancer--assessment of its role in diagnosis].

BACKGROUND: Although Carbohydrate antigen19-9 (CA19-9) is known to be high of its positive rate in blood in pancreatic cancer, etc., recently there have been scattered of cases of urothelial carcinoma in which elevated CA19-9 levels have been detected in both serum and urine. In this study we determined both urine and serum levels of CA19-9 in order to evaluate their diagnostic role of urinary CA19-9.

MATERIALS: A total 82 patients, i.e., 32 with bladder cancer, 4 with renal pelvic/ureteral cancer, 5 with renal cancer, 13 with prostatic cancer, 5 with other malignancies, 10 with prostatic hyperplasia, 6 with urolithiasis, 7 with other benign diseases, served as the subjects of this study.

METHODS: CA19-9 was determined by EIA method in first-morning urine and serum using a CA19-9 measurement kit (Centocor). Urinary values corrected for the creatinine level in the same sample have been used and are shown as U/mg creatinine (Cr). Urinary CA19-9 and urinary cytology were evaluated in some cases. An immunohistochemical study of CA19-9 for surgical specimens was conducted by the ABC method, using a Histo 19-9 kit (COMPAGNIE ORIS INDUSTRIES S.A.).

RESULTS: The cut-off value for serum levels was 37 U/ml, and urine levels were determined in U/mg Cr with a cut-off value of 100 U/mg Cr. The urinary CA19-9 levels was significantly higher (390.9 +/- 934.1 U/mg Cr) in urothelial cancer than in the control group (91.48 +/- 20.0 U/ mg Cr). In urothelial cancer, grade 1 and grade 2 cases were more sensitive than grade 3 cases and they also tended to be high level, although only 27.8% of urothelial cancer patients showed an elevation of serum CA19-9. CA19-9 was detected in all urothelial cancers which could be studied immunohistochemically. In 8 out of 16 superficial cancers CA19-9 was detected in more than 90% of cancer cells, though there were few CA19-9 positive cells in infiltrating cancers. Urinary CA19-9 was more sensitive than urinary cytology, especially in low grade cancers.

CONCLUSION: The determination of urinary CA19-9 may be a useful tumor marker of urothelial cancer, and especially in low grade cancer it may be useful in diagnosing of them because its urinary level is high and it is more sensitive than urinary cytology.