78815
PET-CT, skull to mid-thigh
Positron emission tomography with concurrent computed tomography (PET-CT), skull base to mid-thigh. CMS 2026 global wRVU 1.94, total RVU approximately 12.57, Medicare global allowable approximately $420. The standard oncology staging and surveillance PET-CT field; covers nearly all adult-cancer indications.
When to use it
Use 78815 for the skull base to mid-thigh PET-CT field, which is the standard for most adult oncology indications: lymphoma (initial staging, mid-treatment response, end-of-treatment), lung cancer staging, colorectal cancer staging or recurrence, head and neck cancer surveillance, breast cancer (when indicated), esophageal cancer, melanoma staging, and many other solid tumors. 78816 (whole body) is reserved when distal-extremity coverage is clinically needed (rare; melanoma with distal extremity primary, multi-site disease).
Full guidance
78814 (limited area) is for a focal anatomic region only.
Documentation checklist
- ✓Order with cancer diagnosis and indication (staging, restaging, response assessment, surveillance).
- ✓Radiotracer documented (F-18 FDG most common; F-18 fluciclovine for prostate cancer recurrence; Ga-68 DOTATATE for neuroendocrine; Ga-68 PSMA for prostate cancer; etc.).
- ✓Patient preparation documented (fasting, glucose check for FDG).
- ✓Interpretation with SUVmax measurements, anatomic localization, response criteria (PERCIST, Deauville for lymphoma).
- ✓Comparison to prior PET-CT when applicable.
- ✓Setting modifier; signed report.
Common pitfalls
- !Billing 78816 (whole body) when 78815 (skull to mid-thigh) was actually the field acquired. Whole body is rarely needed and pays more — over-coding risk.
- !Failing to document the radiotracer used. Different tracers have different indications and coverage.
- !Billing 78815 for a known cancer recurrence without prior authorization for many commercial payers. Prior auth is standard.
- !Missing the response-assessment criteria documentation (PERCIST or Deauville for lymphoma). These structured criteria drive treatment decisions and audit defense.
- !Stacking 78815 with diagnostic CT codes when the diagnostic CT is part of the PET-CT acquisition. The CT component is bundled into 78815; do not also bill 74177 separately for the same acquisition.
Payer notes
Medicare covers 78815 for FDA-approved oncology indications under National Coverage Determination. Initial diagnosis (staging) is covered for nearly all solid tumors; surveillance frequency varies by cancer type and NCCN guidelines. Commercial payers require prior authorization. Non-oncology indications (cardiac viability, infection, inflammation) are covered under different criteria — typically the dedicated cardiac PET codes (78429-78433) rather than 78815.