Cxbladder Monitor testing to reduce cystoscopy frequency in patients with bladder cancer

Abstract

Purpose: Bladder cancer surveillance is associated with high costs and patient burden. CxMonitor (CxM), a home urine test, allows patients to skip their scheduled surveillance cystoscopy if CxM-negative indicating a low probability of cancer presence. We present outcomes from a prospective multi-institutional study of CxM to reduce surveillance frequency during the coronavirus pandemic.

Materials and methods: Eligible patients due for cystoscopy from March-June 2020 were offered CxM and skipped their scheduled cystoscopy if CxM-negative. CxM-positive patients came for immediate cystoscopy. The primary outcome was safety of CxM-based management, assessed by frequency of skipped cystoscopies and detection of cancer at immediate or next cystoscopy. Patients were surveyed on satisfaction and costs.

Results: During the study period, 92 patients received CxM and did not differ in demographics nor history of smoking/radiation between sites. 9 of 24 (37.5%) CxM-positive patients had 1 T0, 2 Ta, 2 Tis, 2 T2, and 1 Upper tract urothelial carcinoma (UTUC) on immediate cystoscopy and subsequent evaluation. 66 CxM-negative patients skipped cystoscopy, and none had findings on follow-up cystoscopy requiring biopsy. Six of these patients did not attend follow-up, 4 elected to undergo additional CxM instead of cystoscopy, 2 stopped surveillance, and 2 died of unrelated causes. CxM-negative and positive patients did not differ in demographics, cancer history, initial tumor grade/stage, AUA risk group, or number of prior recurrences. Median satisfaction (5/5, IQR 4-5) and costs (26/33, 78.8% no out-of-pocket costs) were favorable.

Conclusions: CxM safely reduces frequency of surveillance cystoscopy in real-world settings and appears acceptable to patients as an at-home test.

Keywords: Bladder cancer; CxMonitor; Cxbladder Monitor; Recurrence; Skip cystoscopy; Urine test.