ICD-10 Code C00 – Malignant neoplasm of lip (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C00 – Malignant neoplasm of lip
What it is
C00 identifies a malignant tumor arising in the lip. Use it when documentation states primary cancer of the lip, including upper or lower lip, unless a more specific subcategory is documented.
Clinical signs
Clinical features vary; refer to documentation. Commonly recorded findings include a persistent lip lesion, ulceration, induration, bleeding, or a nonhealing mass confirmed as malignant.
When to use this code
Use C00 when the provider documents primary malignant neoplasm of the lip, such as carcinoma of the lip or lip cancer. Code the documented site as specifically as possible if the record identifies upper, lower, or another lip subsite. If the note is unclear, check documentation before assigning the code.
Do not use for
Do not use C00 for benign lip lesions, dysplasia, or nonmalignant ulcers. Do not use it when the cancer is documented as secondary or metastatic to the lip.
Coding tip
Match the code to the exact lip site documented, and query for laterality or subsite detail when the record is incomplete.