C56.9 — Malignant neoplasm of unspecified ovary
C56.9 is a billable, specific ICD-10-CM code for malignant neoplasm of unspecified ovary. It is valid for submission on a claim.
Other codes that can never be billed with C56.9
These codes carry an Excludes1 note pointing at C56.9. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading C56.9 alone.
- C75Malignant neoplasm of other endocrine glands and related structures
Risk adjustment
C56.9 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
C56.9 is named in 67 Medicare coverage policies — 67 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A52370Billing and Coding: Bevacizumab and biosimilars
- A52450Billing and Coding: Paclitaxel (e.g., Taxol®/Abraxane ™)
- A52450Billing and Coding: Paclitaxel (e.g., Taxol®/Abraxane ™)
- A52453Billing and Coding: Luteinizing Hormone-Releasing Hormone (LHRH) Analogs
How C56.9 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 C56.9.
- Adenocarcinoma›papillocystic›unspecified site
- Adenocarcinoma›pseudomucinous›unspecified site
- Carcinoma›papillocystic›unspecified site
- Carcinoma›pseudomucinous›unspecified site
- Cystadenocarcinoma›mucinous›unspecified site
- Cystadenocarcinoma›papillary›unspecified site
- Cystadenocarcinoma›pseudomucinous›unspecified site
- Cystadenocarcinoma›serous›unspecified site
- Dysgerminoma›unspecified site›female
- Tumor›mucinous of low malignant potential›unspecified site
- Tumor›serous of low malignant potential›unspecified site
- Adenocarcinoma›duct›unspecified site›female
Code history
C56.9 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.
Related codes at this level
Codes that share C56. If C56.9 is not quite right, the correct code is usually one of these.
Questions about C56.9
- Is C56.9 a billable ICD-10-CM code?
- Yes. C56.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does C56.9 sit in the tabular list?
- Neoplasms (C00-D49), in the block Malignant neoplasms of female genital organs (C51-C58).