ICD-10-CM > C00-D49 > C00-C14 > C04 C04 Malignant neoplasm of floor of mouth Non-Billable/Non-Specific Use Additional code to identify:alcohol abuse and dependence (F10.-)history of tobacco dependence (Z87.891)tobacco dependence (F17.-)tobacco use (Z72.0) Codes C04.0Malignant neoplasm of anterior floor of mouthC04.1Malignant neoplasm of lateral floor of mouthC04.8Malignant neoplasm of overlapping sites of floor of mouthC04.9Malignant neoplasm of floor of mouth, unspecified