NEW ORLEANS—A urine cytology stain accurately identifies urothelial carcinoma and may provide a non-invasive alternative to cystoscopy for bladder cancer surveillance, according to research presented at the 2015 American Urological Association meeting.
In a blinded, multicenter study, investigators led by Ofer Yossepowitch, MD, of Rabin Medical Center in Petah Tikva, Israel, tested the accuracy of Zetiq’s CellDetect to distinguish malignant and benign cells by color staining. The plant-based stain targets the cytoplasm; green indicates benign cells and purple-red indicates cancer.
Early morning urine samples were collected from 217 patients with a history of urothelial carcinoma (group 1 patients were undergoing routine cytoscopic surveillance and group 2 TURT/cystectomy) and processed to cytospin smears. Two independent cytopathologists then analyzed each slide; both were blinded to the ultimate diagnosis. Results from the urine cytology stain were compared with the final diagnosis determined by cystoscopy (and biopsy, when necessary).
Among 65 urine smears (1 per patient), CellDetect correctly identified 22 of 25 cancer cases and 27 of 40 healthy cases, reflecting 84% sensitivity and 82% specificity. The researchers highlight that the test showed the same sensitivity across tumors of different grades.
They further noted that CellDetect appeared to outperform the available non-invasive assays (such as NMP-22), particularly for low-grade, low stage bladder tumors. If confirmed by further investigation, the researchers suggest that the cytology stain may aid early detection of bladder cancer.