C31.2
BillableMalignant neoplasm of frontal sinus
HCC Category Mapping
V28HCC 21 — Breast, Prostate, Colorectal and Other Cancers and Tumors
0.545V24HCC 11 — Colorectal, Bladder, and Other Cancers
0.306ESRDHCC 11 — Colorectal, Bladder, and Other Cancers
0.000RxHCCHCC 22 — Cancer, Other Specified Sites
0.000What This Code Means
Cancer of the frontal sinus, the air-filled space in the forehead above the eyebrows.
Coding Tips
- •Frontal sinus cancer is uncommon; verify diagnosis and document any intracranial extension
- •Note involvement of adjacent structures such as the orbit or anterior cranial fossa
Clinical Significance
Frontal sinus cancer is uncommon among paranasal sinus malignancies. Due to the frontal sinus's proximity to the anterior cranial fossa and orbit, these tumors frequently present with intracranial extension. Surgical management is complex, often requiring craniofacial resection, making accurate coding important for reflecting true disease severity and resource needs.
Documentation Requirements
- ✓Pathology confirmation of malignancy with histological type
- ✓Imaging documenting frontal sinus as the primary site
- ✓Assessment of intracranial or orbital extension
- ✓TNM staging and treatment approach
- ✓Distinction from other sinus sites if tumor extends beyond the frontal sinus
Commonly Confused Codes
C31.1 — Ethmoidal sinus cancer: Frontal and ethmoidal sinuses are adjacent; imaging is needed to determine the primary siteC31.8 — Overlapping sites of accessory sinuses: Use when the tumor spans multiple sinusesC41.0 — Bone cancer of skull: Frontal bone involvement from sinus cancer should still be coded as sinus cancerC31.9 — Accessory sinus, unspecified: Use only if the specific sinus cannot be identified
Code Hierarchy
└C31Malignant neoplasm of accessory sinuses└C31.2Malignant neoplasm of frontal sinus
└C31.2Malignant neoplasm of frontal sinus