Malignant neoplasm of accessory sinuses (C31) ICD-10-CM
The C31 code range covers malignant neoplasm of accessory sinuses with 7 ICD-10-CM diagnosis codes. 6 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Codes in the C31 Range 7 codes · 6 billable
- C31 Malignant neoplasm of accessory sinusesNon-billable
- C31.0 Malignant neoplasm of maxillary sinus
- C31.1 Malignant neoplasm of ethmoidal sinus
- C31.2 Malignant neoplasm of frontal sinus
- C31.3 Malignant neoplasm of sphenoid sinus
- C31.8 Malignant neoplasm of overlapping sites of accessory sinuses
- C31.9 Malignant neoplasm of accessory sinus, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the C31 range.
Malignant Ethmoid Sinus Neoplasm
A primary or metastatic malignant neoplasm involving the ethmoid sinus.
Malignant Frontal Sinus Neoplasm
A primary or metastatic malignant neoplasm involving the frontal sinus.
Malignant Maxillary Sinus Neoplasm
A primary or metastatic malignant neoplasm involving the maxillary sinus.
Malignant Paranasal Sinus Neoplasm
A primary or metastatic malignant neoplasm involving the paranasal sinuses.
Malignant Sphenoid Sinus Neoplasm
A primary or metastatic malignant neoplasm involving the sphenoid sinus.
About the C31 Code Range
Malignant neoplasm means cancer. C31 describes cancer of the accessory sinuses.
The subdivisions distinguish the maxillary (C31.0), ethmoidal (C31.1), frontal (C31.2), and sphenoid (C31.3) sinuses. Separate codes describe overlapping sites (C31.8) and an unspecified accessory sinus (C31.9).
Questions About This Page
How many billable codes are in the C31 range?
Of the 7 codes in this range, 6 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the C31 range classify?
The range classifies malignant neoplasm of accessory sinuses. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
