Malignant neoplasm of other sites of lip

This code signifies a cancerous tumor originating in parts of the lip other than the external surface, vermilion border, or commissure. This includes malignant neoplasms affecting the inner mucosal lining, glandular structures, or deeper tissues of the lip. It represents a primary malignancy requiring definitive treatment.

Assign this code when documentation specifies a primary malignant neoplasm of an "other specified site" of the lip, such as the labial mucosa or minor salivary glands within the lip. Supporting documentation should include pathology reports confirming malignancy and precise anatomical location. Do not use for benign lesions or malignancies of the external lip.

• Differentiate carefully between external lip sites (e.g., vermilion border) and internal/other sites.
• Ensure the pathology report confirms malignancy; do not code based solely on clinical suspicion.
• Consider sequencing rules for primary vs. secondary malignancies if applicable.