Malignant neoplasm of commissure of lip

This code signifies a cancerous tumor originating at the corner or junction of the upper and lower lips. This specific anatomical site is crucial for accurate classification of the malignancy. It indicates a primary malignant process rather than a secondary or metastatic lesion.

Apply this code when documentation explicitly states a primary malignant neoplasm located at the commissure of the lip. This diagnosis is typically confirmed by biopsy and pathology reports. Use this code for initial encounters, subsequent treatment, or surveillance of this specific lip cancer.

• Ensure documentation specifies "commissure of lip" to differentiate from other lip sites.
• Do not use for benign lesions or malignancies of the internal oral cavity.
• Consider additional codes for laterality (e.g., right, left) if specified in the documentation, though ICD-9-CM often lacks this specificity for lip sites.