Malignant neoplasm of base of tongue

This code signifies a primary cancerous tumor originating in the base of the tongue. This area is the posterior one-third of the tongue, situated behind the circumvallate papillae and extending to the epiglottis. This malignancy is a type of head and neck cancer.

Apply this code when documentation confirms a primary malignant neoplasm located specifically at the base of the tongue. This diagnosis is typically established through biopsy and imaging studies. Use this code for initial encounters for treatment, as well as for subsequent encounters for active treatment of the primary site.

• Ensure the documentation clearly specifies the "base" of the tongue, not other parts like the anterior two-thirds or unspecified tongue.
• Do not confuse this with benign neoplasms or secondary metastatic lesions to the base of the tongue.
• Properly sequence this code as the primary diagnosis when it is the reason for the encounter, followed by any relevant secondary diagnoses.