Comparison of the bladder tumour antigen test with photodynamic diagnosis in patients with pathologically confirmed recurrent superficial urinary bladder tumours.

Abstract

To verify the sensitivity of the bladder tumour antigen (BTAstat, Bard Urological, Covington, GA) test against the sensitive procedure of photodynamic diagnosis (PDD), in which 5-aminolaevulinic acid (5-ALA, a precursor of fluorescent porphyrins) is absorbed by the tumour and detected by ultraviolet cystoscopy, in the early diagnosis of urinary bladder tumours. Forty-three patients (31 men and 12 women, age range 21-87 years) were assessed after transurethral resection of their bladder tumour using the BTAstat test and PDD. Sixty-nine biopsies from suspect areas of bladder mucosa were taken during cystoscopy under ultraviolet light and all suspect lesions electrocoagulated. Thirty-five patients (81%) had a positive BTAstat test; in these patients PDD detected malignant lesions (17 Ta1G1-2, two T1G2, two T1G3 and 14 Tis). In eight patients (19%) the BTAstat was negative but PDD detected three malignant lesions (two Tis and one TaG1). PDD is valuable for detecting bladder malignancy and can identify small lesions not detected by the BTAstat test.