ICD-10 Code C06.0 – Malignant neoplasm of cheek mucosa (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C06.0 – Malignant neoplasm of cheek mucosa
What it is
C06.0 identifies a malignant tumor arising in the mucosal lining of the cheek, also called the buccal mucosa. Use it when documentation specifies cancer of the inner cheek.
Clinical signs
Findings may include a persistent oral ulcer, mass, pain, bleeding, or difficulty chewing. Clinical features vary; refer to documentation and pathology when available.
When to use this code
Use C06.0 when the provider documents primary cancer of the cheek mucosa, including biopsy-confirmed malignant neoplasm of the buccal mucosa. It may also apply when the record clearly localizes the tumor to the inner cheek. If the site is unclear, check documentation.
Do not use for
Do not use this code for benign oral lesions, inflammatory cheek conditions, or cancers of adjacent oral sites such as the lip, gum, or tongue unless the cheek mucosa is specifically documented.
Coding tip
Code the exact anatomic site stated in the note; if “cheek” is mentioned without mucosal involvement, verify the location before assigning C06.0.