C18 ICD-10-CM Code: Malignant neoplasm of colon
A clear reference for the official code description, hierarchy, and related coding information from the FY 2027 U.S. release.
Official description
C18Malignant neoplasm of colon
ICD-10-CM diagnosis code · United States clinical modification
Where C18 sits
- 1
Chapter 2
Neoplasms (C00-D49)
- 2
Section
Malignant neoplasms of digestive organs (C15-C26)
- 3
Category C18
Malignant neoplasm of colon
- 4
Code C18
Malignant neoplasm of colon
Codes under C18
C18 is a non-billable category. Choose the child code that best matches the documented diagnosis.
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, unspecifiedNotes for this code
Inclusion terms
No inclusion terms are listed for C18.
Code first
No “code first” instruction is listed for C18.
Use additional code
No “use additional code” instruction is listed for C18.
Excludes1
Conditions that should not be reported together with this code.
- malignant carcinoid tumors of the colon (C7A.02-)
Excludes2
Conditions not included here that may be reported separately when present.
No Excludes2 note is listed for C18.
Source and release
- Data release
- U.S. ICD-10-CM · FY 2027
- Effective date
- Oct 1, 2026
- Publisher
- Vero Scribe Inc.
This reference is generated from Vero’s ICD-10-CM description, hierarchy, and code-note dataset. The visible content and structured data share that source.
Frequently asked questions
What does ICD-10-CM code C18 mean?
C18 is the FY 2027 U.S. ICD-10-CM code for “Malignant neoplasm of colon.”
Is C18 a billable or specific ICD-10-CM code?
No. C18 has more specific child codes in the FY 2027 reference data. Select the code that matches the documentation and confirm the active code set and payer requirements.
Where is C18 located in ICD-10-CM?
C18 is listed in Chapter 2, Neoplasms (C00-D49), within Malignant neoplasms of digestive organs (C15-C26) (C15–C26), under category C18, Malignant neoplasm of colon.
What coding notes are listed for C18?
No inclusion terms are listed for C18 in this reference record. No code-first instruction is listed. Excludes1 notes: malignant carcinoid tumors of the colon (C7A.02-). No Excludes2 note is listed.