CPT code 0058U designates the Merkel SmT Oncoprotein Antibody Titer, a Proprietary Laboratory Analyses (PLA) test performed by the University of Washington’s Department of Laboratory Medicine to detect and quantify antibodies to the Merkel cell polyomavirus small T antigen. The assay targets a tumor-specific oncoprotein relevant to Merkel cell carcinoma (MCC), a rare but highly aggressive neuroendocrine skin cancer; as a PLA, the code applies only to this specific test and provider.

This national-level summary highlights coverage and policy relevance for major payers, with Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare included in the overview. The publication describes clinical context for use in MCC surveillance and diagnosis, summarizes typical sites of service and service type, and outlines what readers will find in the full report: payer coverage benchmarks, coding and billing considerations, and clinical context for interpretation.

Readers will learn where CPT code 0058U fits in laboratory service lines, how PLA status affects coding and billing, and the practical implications for hospital and outpatient laboratory operations. Data not available in the input is noted where specific payer coverage determinations, reimbursement rates, and associated taxonomies or ICD-10 linkage are not provided.