C18.9 — Malignant neoplasm of colon, unspecified
C18.9 is a billable, specific ICD-10-CM code for malignant neoplasm of colon, unspecified. It is valid for submission on a claim.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Malignant neoplasm of large intestine NOS
Risk adjustment
C18.9 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:
- HCC 22 Bladder, Colorectal, and Other Cancers0.363 RAF
Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score.
Medicare coverage
C18.9 is named in 83 Medicare coverage policies — 83 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
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How C18.9 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to C18.9.
- Polyposis›coli›adenocarcinoma in
- Polyposis›coli›carcinoma in
- Adenocarcinoma›in›adenomatous›polyposis coli
- Carcinoma›in›adenomatous›polyposis coli
Related codes at this level
Codes that share C18. If C18.9 is not quite right, the correct code is usually one of these.
- C18.0Malignant neoplasm of cecum
- C18.1Malignant neoplasm of appendix
- C18.2Malignant neoplasm of ascending colon
- C18.3Malignant neoplasm of hepatic flexure
- C18.4Malignant neoplasm of transverse colon
- C18.5Malignant neoplasm of splenic flexure
- C18.6Malignant neoplasm of descending colon
- C18.7Malignant neoplasm of sigmoid colon
- C18.8Malignant neoplasm of overlapping sites of colon
Questions about C18.9
- Is C18.9 a billable ICD-10-CM code?
- Yes. C18.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does C18.9 sit in the tabular list?
- Neoplasms (C00-D49), in the block Malignant neoplasms of digestive organs (C15-C26).