The role of collecting bladder wash fluid before biopsy procedure to help the cytological diagnosis of residual tumor.

Background: Urinary cytology has low sensitivity and specificity in urinary neoplasm.

Aim: We planned to assess whether the examination of bladder washing before biopsy (WBB) plays a role in better cytologic diagnosis of bladder wash fluid collected after biopsy procedure (WAB) in papillary urothelial neoplasms.

Materials And Methods: We included 36 patients with papillary lesion of bladder. Prior to the biopsy, the bladder is washed and fluid is collected for cytology; later transurethral resection (TUR) is performed, then bladders are washed again and the fluid is separately collected for cytology. Both fluids were centrifuged and stained with May-Grünwald Giemsa (MGG). First the WAB slides were evaluated and diagnosed. After evaluation of the WBB slides, the WAB slides were rediagnosed. Presence of cellularity, papillary structure, fusiform cells, background bleeding, and cytolysis in WBB and WAB were evaluated separately.

Results: We determined that 31 WBB samples were hypercellular, and 12 of them remained as hypercellular in WAB. Papillary structures were observed in 20 WBB samples; and in one WAB cytology. In 29 cases where no fusiform cells are identified in WBB, 22 showed fusiform cells in WAB. Cytolysis in WABs was noted in 15 cases whose WBBs did not show cytolysis. The decrease in cellularity, papillary structure (P < 0.001, both), cytolysis (P = 0.008), and fusiform cells (P < 0.001) were statistically significant. After seeing the WBB slides, we reevaluated the WAB slides. Out of the eight out of 36 (22.2%) samples diagnosed with degeneration previously, five (62.5%) samples were rediagnosed as benign, two (25%) as cytologic atypia which favor reactive, and one (12.5%) as malignant.

Conclusion: Due to the better quality, initial evaluation of WBB may help more effective diagnoses of WAB slides.