HCPCS Level II code A9591 identifies Fluoroestradiol F 18, a diagnostic radiopharmaceutical supplied in a 1 millicurie unit for PET molecular imaging. This agent is used in nuclear medicine to image estrogen receptor expression and can inform diagnosis and treatment planning in oncology. Nationally, accurate coding for radiopharmaceuticals supports appropriate billing, clinical tracking, and reimbursement consistency for high-cost imaging agents.

Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of clinical context for the agent, benchmarks and common payer coverage patterns, and relevant billing considerations for institutional and outpatient imaging sites. The publication highlights typical service settings, common modifiers in use (for reference), and implications for claims processing workflows.

The report provides a concise reference for revenue cycle, coding, and clinical teams on how A9591 is represented in claim lines, what to expect in payer handling, and what operational elements are relevant when administering and billing this PET radiopharmaceutical. Data not available in the input will be noted where applicable.