Detection of recurrent transitional cell carcinoma of the bladder with nuclear matrix protein-22 in a follow-up setting

Objective: To evaluate the use of NMP22 as a diagnostic test for recurrent transitional cell carcinoma (TCC) of the bladder in a follow-up setting. Methods: In 191 patients followed up after resection of a Ta or T1 TCC the results of 431 NMP22 tests were compared with routine cystoscopic examinations. Results: Sensitivity of NMP22 was better for detecting high grade Ta and T1 recurrent tumours (86-100%) than for detecting low grade Ta recurrences (22%) (p = 0.0001). A negative NMP22 result increased the likelihood of a patient not having a recurrence from 85 to 89%. When the primary tumour was high grade or T1, NMP22 detected recurrent TCC with a higher sensitivity compared to low grade and Ta tumours (p = 0.001). Patients with multiple consecutive true-negative NMP22 results during follow-up did not have an improved recurrence free survival. Conclusion: In a follow-up setting the sensitivity of NMP22 is low for the detection of recurrent low grade Ta tumours. Especially patients with low risk primary tumours do not seem to be suitable for follow-up with NMP22.