C56.9 — Malignant neoplasm of unspecified ovary
Is C56.9 billable?
Yes, but C56.9 is an unspecified code. C56.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, C56.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting C56.9 — the more specific alternatives are listed below.
C56.9 at a glance
| Code | C56.9 |
|---|---|
| Description | Malignant neoplasm of unspecified ovary |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does C56.9 group to?
C56.9 sits in MDC 13 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 731Uterine and Adnexa Procedures for Malignancy with MCCsurgical
- 732Uterine and Adnexa Procedures for Malignancy with CCsurgical
- 733Uterine and Adnexa Procedures for Malignancy without CC/MCCsurgical
As a secondary diagnosis, C56.9 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is C56.9 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to C56.9. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Cancer › ovarian
- Adenocarcinoma › papillocystic › unspecified site
- Adenocarcinoma › pseudomucinous › unspecified site
- Carcinoma › papillocystic › unspecified site (malignant)
- Carcinoma › pseudomucinous › unspecified site (malignant)
- 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
Use additional code — inherited from C56
Report an additional code alongside C56.9 to fully describe the condition. C56.9 is sequenced first.
- code to identify any functional activity
How long has C56.9 existed?
C56.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.