Malignant neoplasm of tonsil (C09) ICD-10-CM
The C09 code range covers malignant neoplasm of tonsil with 5 ICD-10-CM diagnosis codes. 4 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Use Additional Code
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.
- code to identify:
- alcohol abuse and dependence F10
- exposure to environmental tobacco smoke Z77.22
- exposure to tobacco smoke in the perinatal period P96.81
- history of tobacco dependence Z87.891
- occupational exposure to environmental tobacco smoke Z57.31
- tobacco dependence F17
- tobacco use Z72.0
Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
Codes in the C09 Range 5 codes · 4 billable
About the C09 Code Range
The ICD-10 code C09 and its subcodes identify malignant neoplasms specifically located in the tonsil area. These codes are used to report cancers originating in different parts of the tonsils, aiding precision in diagnosis and treatment documentation.
The main code C09 covers malignant tumors of the tonsil, while subcodes provide further detail: C09.0 designates cancer in the tonsillar fossa, often referred to in clinical terms such as squamous cell carcinoma of the lateral wall of the oropharynx or primary malignant tumors of the tonsillar fossa. Code C09.1 captures malignancies in the tonsillar pillars—either anterior or posterior—and includes synonyms like malignant tumor of the tonsillar pillar and primary squamous cell carcinoma of this region. For tumors spanning multiple tonsil sites, C09.8 applies, describing overlapping malignant neoplasms of the tonsil. When the exact location within the tonsil is unspecified, C09.9 is used. This category includes common names such as tonsil carcinoma or primary squamous cell carcinoma of Waldeyer's ring. These detailed codes help healthcare professionals accurately document specific tonsil cancers for effective patient care and insurance purposes.
Questions About This Page
How many billable codes are in the C09 range?
Of the 5 codes in this range, 4 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the C09 range classify?
The range classifies malignant neoplasm of tonsil. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
