CPT code 79999 is an unlisted CPT procedure code used to report radiopharmaceutical therapy procedures that lack a specific, dedicated code. As a catch‑all for novel or uncommon therapeutic radiopharmaceutical services, 79999 matters nationally because it affects billing clarity, clinical documentation requirements, and payer adjudication for advanced nuclear medicine treatments. Payers commonly involved in coverage and payment decisions include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare.

Readers will find a concise overview of the clinical context for using 79999, how payers typically approach unlisted radiopharmaceutical therapy claims, and the operational implications for facility and professional billing. The publication covers benchmarks for utilization where available, common administrative and documentation practices tied to unlisted procedure reporting, and policy considerations for claim review and prior authorization. It also outlines typical sites of service for these procedures and the kinds of supporting documentation that payers expect when adjudicating claims submitted with 79999.

The report is national in scope and focuses on billing and policy implications rather than clinical guidance. Data not available in the input will be noted where relevant.