ICD10BillableValid for clinical use
ICD-10 Code C01: Malignant neoplasm of base of tongue
C01 is a billable ICD-10 diagnosis code used to classify Malignant neoplasm of base of tongue in medical records and claims. You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records. ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Neoplasms (C00-D49).
Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026
What is this code?
ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Neoplasms (C00-D49).
When is it used?
- May be used when a clinician documents malignant neoplasm of base of tongue in a patient's medical record.
- May appear in hospital records, claims, referrals, and clinical documentation.
- This code can be used as a clinically usable diagnosis entry in standardized coding workflows.
What it does not mean
- A code alone does not explain severity, treatment plan, or outcome.
- A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
Code hierarchy
chapter
2Neoplasms (C00-D49)
block
C00-C96Malignant neoplasms
block
C00-C75Malignant neoplasms, stated or presumed to be primary (of specified sites), and certain specified histologies, except neuroendocrine, and of lymphoid, hematopoietic and related tissue
block
C00-C14Malignant neoplasms of lip, oral cavity and pharynx
currentC00-C14
Official coding notes
Inclusion terms
- Malignant neoplasm of dorsal surface of base of tongue
- Malignant neoplasm of fixed part of tongue NOS
- Malignant neoplasm of posterior third of tongue
Applicable to
- code to identify:
- alcohol abuse and dependence (F10.-)
- history of tobacco dependence (Z87.891)
- tobacco dependence (F17.-)
- tobacco use (Z72.0)
Use additional code
- code to identify:
- alcohol abuse and dependence (F10.-)
- history of tobacco dependence (Z87.891)
- tobacco dependence (F17.-)
- tobacco use (Z72.0)
Where you may see this code
You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.
Related specialists
OncologistGeneral Physician
Related codes
C00Malignant neoplasm of lipcategoryC02Malignant neoplasm of other and unspecified parts of tonguecategoryC03Malignant neoplasm of gumcategoryC04Malignant neoplasm of floor of mouthcategoryC05Malignant neoplasm of palatecategoryC06Malignant neoplasm of other and unspecified parts of mouthcategoryC07Malignant neoplasm of parotid glandcodeC08Malignant neoplasm of other and unspecified major salivary glandscategoryC09Malignant neoplasm of tonsilcategoryC10Malignant neoplasm of oropharynxcategoryC11Malignant neoplasm of nasopharynxcategoryC12Malignant neoplasm of pyriform sinuscode
Sibling codes
C00Malignant neoplasm of lipC02Malignant neoplasm of other and unspecified parts of tongueC03Malignant neoplasm of gumC04Malignant neoplasm of floor of mouthC05Malignant neoplasm of palateC06Malignant neoplasm of other and unspecified parts of mouthC07Malignant neoplasm of parotid glandbillableC08Malignant neoplasm of other and unspecified major salivary glandsC09Malignant neoplasm of tonsilC10Malignant neoplasm of oropharynxC11Malignant neoplasm of nasopharynxC12Malignant neoplasm of pyriform sinusbillableC13Malignant neoplasm of hypopharynxC14Malignant neoplasm of other and ill-defined sites in the lip, oral cavity and pharynx
Coverage-related procedures and services
CPT 81479high
UNLISTED MOLECULAR PATHOLOGY PROCEDURE
Source: CMS coverage guidance
CPT 81445high
SOLID ORGAN NEOPLASM, GENOMIC SEQUENCE ANALYSIS PANEL, 5-50 GENES, INTERROGATION FOR SEQUENCE VARIANTS AND COPY NUMBER VARIANTS OR REARRANGEMENTS, IF PERFORMED; DNA ANALYSIS OR COMBINED DNA AND RNA ANALYSIS
Source: CMS coverage guidance
CPT 0543Uhigh
ONCOLOGY (SOLID TUMOR), NEXT-GENERATION SEQUENCING OF DNA FROM FORMALIN-FIXED PARAFFIN-EMBEDDED (FFPE) TISSUE OF 517 GENES, INTERROGATION FOR SINGLE-NUCLEOTIDE VARIANTS, MULTI-NUCLEOTIDE VARIANTS, INSERTIONS AND DELETIONS FROM DNA, FUSIONS IN 24 GENES AND SPLICE VARIANTS IN 1 GENE FROM RNA, AND TUMOR MUTATION BURDEN
Source: CMS coverage guidance
CPT 0329Uhigh
ONCOLOGY (NEOPLASIA), EXOME AND TRANSCRIPTOME SEQUENCE ANALYSIS FOR SEQUENCE VARIANTS, GENE COPY NUMBER AMPLIFICATIONS AND DELETIONS, GENE REARRANGEMENTS, MICROSATELLITE INSTABILITY AND TUMOR MUTATIONAL BURDEN UTILIZING DNA AND RNA FROM TUMOR WITH DNA FROM NORMAL BLOOD OR SALIVA FOR SUBTRACTION, REPORT OF CLINICALLY SIGNIFICANT MUTATION(S) WITH THERAPY ASSOCIATIONS
Source: CMS coverage guidance
CPT 0250Uhigh
ONCOLOGY (SOLID ORGAN NEOPLASM), TARGETED GENOMIC SEQUENCE DNA ANALYSIS OF 505 GENES, INTERROGATION FOR SOMATIC ALTERATIONS (SNVS [SINGLE NUCLEOTIDE VARIANT], SMALL INSERTIONS AND DELETIONS, ONE AMPLIFICATION, AND FOUR TRANSLOCATIONS), MICROSATELLITE INSTABILITY AND TUMOR-MUTATION BURDEN
Source: CMS coverage guidance
CPT 0244Uhigh
ONCOLOGY (SOLID ORGAN), DNA, COMPREHENSIVE GENOMIC PROFILING, 257 GENES, INTERROGATION FOR SINGLE-NUCLEOTIDE VARIANTS, INSERTIONS/DELETIONS, COPY NUMBER ALTERATIONS, GENE REARRANGEMENTS, TUMOR-MUTATIONAL BURDEN AND MICROSATELLITE INSTABILITY, UTILIZING FORMALIN-FIXED PARAFFIN-EMBEDDED TUMOR TISSUE
Source: CMS coverage guidance
Mapped diagnoses and classifications
SNOMED_CT 271943005high
Carcinoma of base of tongue
Source: SNOMED International ICD-10 map
SNOMED_CT 275490009high
Carcinoma of tongue base - dorsal surface
Source: SNOMED International ICD-10 map
SNOMED_CT 363376007high
Malignant neoplasm of base of tongue
Source: SNOMED International ICD-10 map
SNOMED_CT 187631006high
Malignant neoplasm of base of tongue dorsal surface
Source: SNOMED International ICD-10 map
SNOMED_CT 1259438002high
Primary carcinoma of base of tongue
Source: SNOMED International ICD-10 map
SNOMED_CT 1259318004high
Primary carcinoma of tongue base - dorsal surface
Source: SNOMED International ICD-10 map
Coding guidelines
Compatibility
Legacy and official ICD code match exactly.
Legacy codes
C01
Common synonyms
Malignant neoplasm of base of tongue
Frequently asked questions
About this content
This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.