ICD-10-CM 2027 diagnosis code

C56Malignant neoplasm of ovary

Not billable — use a more specific code

C56 is a header code, so it can't be reported by itself. Choose one of the 4 more specific codes beneath it.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About C56

C56 is the ICD-10-CM diagnosis code for malignant neoplasm of ovary. It belongs to block C51-C58 (malignant neoplasms of female genital organs) and chapter 2 (neoplasms). It is a header code, so it can't be reported by itself; one of its 4 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: C56.1 (ovary), C56.2 (ovary), C56.3 (ovaries) and C56.9 (ovary).

Use an additional code to identify any functional activity.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Specific codes under C56

Coding notes

Use additional codeAdd a secondary code to fully describe the condition

code to identify any functional activity

Notes that apply from higher levels

Instructions written at a parent level also apply to C56.

Broader instructions also apply from C51-C58 Malignant neoplasms of female genital organs and Chapter 2: Neoplasms.

Alphabetic index entries

26 entries

Terms in the official ICD-10-CM index that lead to C56.

Table of Drugs & Neoplasms entries

Neoplasm, neoplastic › corpus › albicans — Malignant Primary
Neoplasm, neoplastic › ovary — Malignant Primary

Codes whose notes reference C56

C75Excludes1
R18.0Code first
Z17Code first

Code history

2016
2017
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2020
2021
2022
2023
2024
2025
2026
2027

FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
No changes since FY2016.

Common questions about C56

Is C56 billable?: No. C56 is a header code. Report one of its more specific subcodes instead.