NMP-22 urine assays for bladder cancer detect nuclear mitotic apparatus protein 1 (NUMA-1) using monoclonal antibodies. This protein can be elevated in the urine if bladder cancer cells that are rapidly dividing are present. It is not a partticularly specific tests, with many described non-cancer factors that elevate its values, and there is ongoing controversy as to whether its advantages in sensitivity over urine cytology are sufficient to recommend it as a routine screening test for bladder cancer.
Medicare has granted this test a CLIA exception but there are no guidelines that support its use at this time.
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