Upper urinary tract washings outperform voided urine specimens to detect upper tract high-grade urothelial carcinoma

Background: Cytological examination of voided urine (VU) can reliably diagnose high-grade urothelial carcinoma (HGUC) of the lower urinary tract, but its value in the diagnosis of upper tract HGUC (UTHGUC) is less well-established. To clarify the utility of VU in the setting of UTHGUC, we examined urinary specimens from patients with UTHGUC on follow-up surgical pathology. Methods: 52 VU specimens (47 patients) with subsequent biopsy-proven UTHGUC were identified over a 12-year period; 32 had a corresponding upper tract urinary washing (UW) specimen. Patients with concurrent bladder HGUC were excluded. The diagnoses of VU specimens were tabulated and compared to those of UWspecimens. Results: Three UWspecimens had a less severe diagnosis, 8 had the same diagnosis, and 21 had a more severe diagnosis than the corresponding VU specimen from the same patient. Significantly more UW specimens demonstrated high-risk features as compared with VU specimens (P=.003). In specimens with atypia, a definitive diagnosis of HGUC was made significantly more often on UW vs. VU specimens (P=.003). Conclusions: Among patients with confirmed UTHGUC, 50% of preceding VU specimens demonstrated high-grade features compared to almost 90% of UW specimens. Though VU cytology shows atypia in the majority of cases, it performs inferiorly to UW for the detection of UTHGUC.