ICD-10 Code C00.9 – Malignant neoplasm of lip, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C00.9 – Malignant neoplasm of lip, unspecified
What it is
This code identifies a malignant tumor of the lip when the exact site is not documented. Use it for a lip cancer diagnosis without further specification of upper, lower, or commissure.
Clinical signs
Clinical features vary; refer to documentation. Common findings may include a persistent lip lesion, ulceration, induration, bleeding, or a nonhealing area suspicious for malignancy.
When to use this code
Use C00.9 when the provider documents malignant neoplasm of the lip but does not specify the exact lip subsite. It is also appropriate when the record confirms lip cancer and laterality or exact location is unavailable. If the note is more specific, code the documented subsite instead.
Do not use for
Do not use this code for benign lip lesions, dysplasia, or premalignant conditions. If the documentation identifies a specific lip site, such as upper or lower lip, choose the more specific code.
Coding tip
Review the pathology, operative note, and assessment carefully; if the site is stated, code that subsite rather than the unspecified category.