Evaluation of a double-monoclonal radioimmunoassay for the measurement of carcinoembryonic antigen in the urine of patients with bladder cancer.

A double-monoclonal radioimmunoassay (RIA) has been used to detect urinary carcinoembryonic antigen (CEA) in 204 patients attending for diagnostic cystoscopy. Elevated levels of urinary CEA were found in 50% of patients with bladder tumours, and these levels correlated with both the grade and stage of the tumour. The sensitivity proved to be 58% and the specificity 74%, which compares with previous studies using polyclonal RIA kits. As a monitoring test, urinary CEA proves to be as useful as urine cytology. The use of a more specific assay does not increase the clinical value of the test which still lacks the sensitivity and specificity needed to allow it to be used to monitor recurrence of low grade tumours (Ta, Tis and T1).