2026 ICD-10-CM Diagnosis Code C56Malignant neoplasm of ovary

ICD-10-CM Codes›C00–D49›C51-C58›C56

ICD-10-CM C56
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C56 is a non-billable ICD-10-CM category code for malignant neoplasm of ovary, so it cannot be submitted on claims. Use a more specific code from this category instead, such as C56.1, C56.2, C56.3, and C56.9.

Code Identity

ICD-10-CM Code
C56
Billable Status
No — Non-Billable Category
Code Describes
Malignant neoplasm of ovary
Chapter
C51-C58
Malignant neoplasms of female genital organs

Code Classification

ChapterC00–D49Neoplasms
SectionC51-C58Malignant neoplasms of female genital organs
CategoryC56Malignant neoplasm of ovary
This CodeC56Malignant neoplasm of ovary

Specific Coding for Malignant neoplasm of ovaryOverview

Non-specific codes like C56 require more characters. Use one of these billable codes instead:

  • Use C56.1 for Malignant neoplasm of right ovary

  • Use C56.2 for Malignant neoplasm of left ovary

  • Use C56.3 for Malignant neoplasm of bilateral ovaries

  • Use C56.9 for Malignant neoplasm of unspecified ovary

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Use Additional Code

  • code to identify any functional activity

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Adenofibroma
      • endometrioid
        • malignant
    • Brenner
      • tumor (benign)
        • malignant
    • Carcinoma(malignant)
      • granulosa cell
    • Dermoid(cyst)
      • with malignant transformation
    • Teratoma(solid)
      • ovary
        • embryonal, immature or malignant
    • Thecoma
      • malignant
    • Tumor
      • Brenner
        • malignant
    • Tumor
      • dermoid
        • with malignant transformation
    • Tumor
      • granulosa cell
        • malignant
    • Tumor
      • granulosa cell-theca cell
        • malignant
    • Tumor
      • papillary
        • mucinous of low malignant potential

Patient EducationClinical

Ovarian Cancer

Cancer is a disease in which abnormal cells in the body grow out of control and form a tumor. Ovarian cancer is a cancerous tumor that forms in the tissues of an ovary. The ovaries are a pair of female reproductive glands that make eggs and female hormones.

The full article covers:

  • What is ovarian cancer?
  • What are the types of ovarian cancer?
  • What causes ovarian cancer?
  • Who is more likely to develop ovarian cancer?
  • What are the symptoms of ovarian cancer?
  • How is ovarian cancer diagnosed?
  • What are the treatments for ovarian cancer?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About C56Overview

Is C56 (Malignant neoplasm of ovary) a billable code?

No. This is a category header that groups the codes for malignant neoplasm of ovary, and headers cannot be submitted on claims. Claims for malignant neoplasm of ovary need a more specific code from this category, such as C56.1, C56.2, and C56.3.