ENDOSCOPIC BRUSH CYTOLOGY OF THE UPPER URINARY-TRACT - EVALUATION OF ITS EFFICACY AND POTENTIAL LIMITATIONS IN DIAGNOSIS

OBJECTIVE: To evaluate the efficacy of endoscopic brush cytology in di agnosing transitional cell carcinoma of the upper urinary tract. STUDY DESIGN: Sixty-three endoscopic brush cytology specimens from 48 patie nts were compared with corresponding cytologic specimens obtained by i rrigation and catheterization as well as histologic specimens. RESULTS : Twenty patients (25 brushes) had histologically documented transitio nal cell carcinoma (TCC) or carcinoma in situ (CIS) of either the uret er or renal pelvis. Among these, 8 (32%) of the brush samples were rep orted as positive for TCC, 10 (40%) atypical or suspicious, and 7 (28% ) negative. The seven negative cases were ultimately shown to be low g rade (I-II/IV) TCC. Combining atypical and positive diagnoses, the cal culated sensitivity for diagnosis of TCC by this technique was 72%. Th e irrigations or catheterized urines from these same patients yielded lower sensitivity, 48%, and detected only higher grade lesions. Ten pa tients were proven histologically to have nonneoplastic disease (hydro ureter, obstruction, inflammation). Sixteen of the 17 brush specimens from these patients were negative, resulting in a specificity of 94%. In the remaining 18 patients (21 brushes) there were 17 negatives and 4 atypicals. Concomitant cytology supported the brush diagnosis in all but one sample. CONCLUSION: Brash cytology is a specific and more sen sitive sampling method than irrigation or catheterized urine in detect ing TCC of the upper urinary tract. Brush cytology does not appear to be successful in diagnosing dysplasia or CIS. As with urinary cytology in general, the technique is less effective in diagnosing low grade ( I and II) lesions.