CPT code 82977 designates a laboratory assay that measures gamma–glutamyltransferase (GGT) in serum. GGT testing is a common biochemical marker used to evaluate liver function and detect injury to the liver or bile ducts; it is also elevated in some primary and metastatic hepatic or biliary cancers. Nationally, GGT testing is an important component of diagnostic workups for hepatobiliary disease and for monitoring patients with suspected cholestasis or hepatotoxic exposure.

Key payers included in the analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise clinical context for CPT code 82977, the typical sites where the service is delivered, and the typical service type. The publication presents benchmarks and policy-relevant observations about lab reimbursement and coverage landscapes, operational considerations for laboratory delivery of the test, and how CPT code 82977 fits into diagnostic pathways for liver and biliary disease.

This summary targets clinicians, laboratory managers, billing professionals, and policy analysts seeking a practical reference for the role and use of CPT code 82977 in clinical practice and payer coverage frameworks. Data not available in the input will be noted where applicable in detailed sections.