B5 tumour marker and urine cytology in diagnosis and follow-up of transitional cell bladder cancer.

The correlation between a new tumor marker, B5, and tumour behaviour in bladder cancer was recorded and an assessment made of the value of combining the B5 test with urine cytology for predicting the presence of tumour. The study group included 57 new patients, of whom 32 were B5 positive at diagnosis and were well marked by B5 on follow-up. There were no false positive shifts in new patients who became free of observable tumour, whilst 1 of 13 patients with persistent disease showed a false negative shift. When the findings from 199 cystoscopies were compared with the results of B5 and urine cytology, B5 was found to improve the prediction of recurrent tumour over cytology alone. Moreover, a high incidence of occult malignancy (7/19) was found in patients where cystoscopy had failed to show recurrence but whose combined marker results were both positive.