Summary & Overview
HCPCS S0170: Anastrozole, Oral, 1 mg
HCPCS Level II code S0170 designates anastrozole, oral, 1 mg — an oral aromatase inhibitor used in hormone receptor–positive breast cancer care. Nationally, this code is important for accurate drug identification, pharmacy billing, and monitoring utilization of oral antineoplastic therapies. Proper coding supports claims adjudication, benefit determination, and drug cost management across payers.
Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise clinical context for S0170, an overview of how this code fits into outpatient pharmacy and ambulatory oncology care, and what to expect in payer coverage patterns and billing workflows. The publication summarizes common billing practices, outlines benchmarks and utilization considerations, and highlights areas where coding clarity impacts reimbursement and patient access. Policy updates and payer-specific guidance that affect oral oncology benefit design and prior authorization practices are described at a national level.
This piece is intended for clinicians, billing professionals, pharmacy administrators, and policy analysts seeking a clear reference for HCPCS Level II code S0170 and its role in outpatient antineoplastic therapy billing and coverage.
Billing Code Overview
HCPCS Level II code S0170 represents anastrozole, oral, 1 mg. This code denotes a prescription oral medication formulation of anastrozole commonly used in oncologic care.
Service type: Oral antineoplastic (hormonal) therapy
Typical site of service: Outpatient pharmacy or clinician‑administered oral medication dispensed in ambulatory settings
Clinical & Coding Specifications
Clinical Context
Anastrozole (S0170) is an oral aromatase inhibitor commonly prescribed for postmenopausal women with estrogen receptor–positive breast cancer. A typical patient is a postmenopausal woman recently treated with surgery and/or radiation and prescribed daily Anastrozole, oral, 1 mg for adjuvant hormonal therapy or for metastatic disease to reduce estrogen production. The clinical workflow includes an oncology or advanced practice visit for treatment planning, baseline assessment of bone density and lipid profile, counseling on side effects (arthralgia, osteoporosis risk, hot flashes), and issuance of a written prescription or clinic-administered supply billed using the HCPCS Level II code S0170. Follow-up visits occur at regular intervals (every 3–6 months initially) to assess tolerance, adherence, laboratory monitoring, and bone health management; dose changes are uncommon because Anastrozole is available in a fixed 1 mg oral tablet.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | Default/No modifier used | Use when no special circumstances apply to the service billed with . |