Question: To monitor bladder cancer patients for possible recurrence by detecting possible urothelial carcinoma cells in urine, our lab performs the UroVysion® FISH test. I've been told that we should code this as 88399 or 88199 - which is correct? Maine Subscriber Answer: You should not report the UroVysion® FISH test with either unlisted code that you mentioned: 88399 (Unlisted surgical pathology procedure) or 88199 (Unlisted cytopathology procedure). More specific codes accurately describe the test, so you should report either 88120 (Cytopathology, in situ hybridization (eg, FISH), urinary tract specimen with morphometric analysis, 3-5 molecular probes, each specimen; manual) or 88121 (... using computer-assisted technology) as appropriate. UroVysion® FISH detection for recurrent bladder cancer consists of four fluorescent probes that detect urothelial carcinoma cells in urine. Although CPT® instruction does tell you to use 88399 for a urinary tract cytology test with more than five probes, that doesn't apply to UroVysion®, which has four probes.