2026 ICD-10-CM Diagnosis Code C03.1Malignant neoplasm of lower gum
ICD-10-CM Codes›C00–D49›C00-C14›C03
- Billable — Valid for Submission
- Chronic Condition
C03.1 is a billable ICD-10-CM diagnosis code for malignant neoplasm of lower gum. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 146 through 148. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Head and neck cancers - lip and oral cavity.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Carcinoma of lower gum
- Malignant neoplasm of gum of mandible
- Neoplasm of lower gum
- Primary carcinoma of lower gum
- Primary malignant neoplasm of gum
- Primary malignant neoplasm of lower gum
- Primary squamous cell carcinoma of lower gum
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Table of NeoplasmsClinical
Anatomical sites in the Table of Neoplasms that reference this code family.
| Site | Malig. Primary | Malig. Secondary | Ca in situ | Benign | Uncertain | Unspec. |
|---|---|---|---|---|---|---|
| alveolar › mucosa › lower | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
| alveolar › ridge or process › carcinoma › lower | C03.1 | C79.8 | – | – | – | – |
| alveolar › ridge or process › mucosa › lower | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
| alveolus › lower | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
| gingiva (alveolar) (marginal) › lower | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
| gingiva (alveolar) (marginal) › mandibular | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
| gum › lower | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
| interdental papillae › lower | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
| jaw › soft tissues › lower | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
| mandible › alveolar | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
| mandible › alveolar › mucosa (carcinoma) | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
| mucosa › alveolar (ridge or process) › lower | C03.1 | C79.89 | D00.03 | D10.39 | D37.09 | D49.0 |
Patient EducationClinical
Oral Cancer
Oral cancer is cancer of the mouth. It is a type of head and neck cancer. Most oral cancers are squamous cell cancers. They begin in the flat cells that cover the surfaces of your mouth, tongue, and lips. The cancer cells may spread into deeper tissue as the cancer grows.
The full article covers:
- What is oral cancer?
- Who is more likely to develop oral cancer?
- What are the symptoms of oral cancer?
- How is oral cancer diagnosed?
- What are the treatments for oral cancer?
- Can oral cancer be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert C03.1 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About C03.1Overview
Is C03.1 (Malignant neoplasm of gum) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report malignant neoplasm of lower gum on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does C03.1 group to?
When malignant neoplasm of lower gum is the principal diagnosis on an inpatient stay, it groups to MS-DRG 146, 147, 148, with relative weights from 0.7971 to 2.1174 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of C03.1?
Under the General Equivalence Mappings, malignant neoplasm of lower gum converts to ICD-9-CM 143.1 (malig neo lower gum). The mapping is a direct match.
Footnotes
[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:
- The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
- The condition places limitations on self-care, independent living, and social interactions.
