Summary & Overview
HCPCS G9085: Colon Cancer Disease Status, Adenocarcinoma, T4 N0 M0
HCPCS Level II code G9085 documents a specific oncology disease-status classification for colon cancer: invasive disease with adenocarcinoma as the predominant histology, initially staged as T4, N0, M0, and with no evidence of progression, recurrence, or metastasis. The code is intended for use in a Medicare-approved demonstration project and standardizes reporting of a defined disease-status state. Nationally, such codes support consistent documentation for clinical tracking, outcomes evaluation, and demonstration-program reporting in oncology care.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of the clinical context for using G9085, the typical settings where the code is reported, and the implications for documentation and reporting in demonstration projects. The publication also summarizes common modifiers associated with similar HCPCS Level II billing and notes where input data are not available.
This summary provides clinicians, clinical coders, and health policy staff with a concise reference to the code's purpose, clinical scope, and expected site-of-service. It highlights the role of G9085 in standardized disease-status reporting for colon adenocarcinoma within demonstration-program workflows and administrative reporting at a national level.
Billing Code Overview
HCPCS Level II code G9085 describes oncology disease status for colon cancer limited to invasive cancer with adenocarcinoma as the predominant cell type, where the extent of disease was initially established as t4, n0, m0 and there is no evidence of disease progression, recurrence, or metastases. This code is designated for use in a Medicare-approved demonstration project.
Service type: Oncology — disease status assessment and documentation
Typical site of service: Hospital outpatient or cancer center/oncology clinic, where diagnostic staging and disease-status evaluations for colon cancer are performed.
Clinical & Coding Specifications
Clinical Context
A 62-year-old patient with a prior diagnosis of invasive colon adenocarcinoma (predominant cell type) presents for enrollment and periodic reporting in a Medicare-approved oncology demonstration project. Initial staging documented tumor invasion through the visceral peritoneum or into adjacent structures (T4), no regional lymph node involvement (N0), and no distant metastasis (M0). The patient completed definitive surgical resection with negative margins and no adjuvant evidence of recurrence on recent imaging and carcinoembryonic antigen (CEA) surveillance. The clinical workflow includes: referral from surgical oncology or medical oncology to the demonstration project coordinator; documentation of baseline disease status (histopathology, operative report, pathology staging T4 N0 M0); review of recent cross-sectional imaging (CT or MRI) and labs confirming no progression; submission of required demonstration project case report forms and billing using G9085; and routine follow-up visits for surveillance per protocol. Typical site of service is an outpatient oncology clinic or cancer center coordinated through a Medicare-approved demonstration project.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|