C18
⚠ Non-billable (Header)Malignant neoplasm of colon
Neoplasms (C00-D49)
⚠️ This is a category header code — not billable. Use a more specific child code below.
❌ Excludes1
directCannot be coded with C18
- • malignant carcinoid tumors of the colon (C7A.02-)
Child Codes (10)
C18.0Malignant neoplasm of cecumC18.1Malignant neoplasm of appendixC18.2Malignant neoplasm of ascending colonC18.3Malignant neoplasm of hepatic flexureC18.4Malignant neoplasm of transverse colonC18.5Malignant neoplasm of splenic flexureC18.6Malignant neoplasm of descending colonC18.7Malignant neoplasm of sigmoid colonC18.8Malignant neoplasm of overlapping sites of colonC18.9Malignant neoplasm of colon, unspecified
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CodeC18
BillableNo — Header code
CategoryNeoplasms (C00-D49)
Excludes11 rule(s)
Excludes20 note(s)
Child codes10
Data Source
CMS ICD-10-CM 2026 Tabular List
Updated October 1, 2025 (FY2026)