2026 ICD-10-CM Diagnosis Code N64.89Other specified disorders of breast

ICD-10-CM Codes›N00–N99›N60-N65›N64

ICD-10-CM N64.89
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

N64.89 is a billable ICD-10-CM diagnosis code for other specified disorders of breast. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 600 through 601. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nonmalignant breast conditions.

This medical diagnosis code is frequently used in OB/GYN medical specialties to designate conditions such lump in breast and other disorders of the breast.

Code Identity

ICD-10-CM Code
N64.89
Billable Status
Yes — Valid for Submission
Code Describes
Other specified disorders of breast
Short Description
Other specified disorders of breast
Same as the full description in the CMS dataset.
Parent Code
N64.8
Other specified disorders of breast

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN60-N65Disorders of breast
CategoryN64Other disorders of breast
This CodeN64.89Other specified disorders of breast

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abnormal breast function
  • Abnormal breast nipple shape
  • Bilateral pendulous breasts
  • Breast hematoma
  • Breast hematoma due to non-traumatic cause
  • Breast seroma
  • Calcification of breast
  • Deformity of breast
  • Delayed development of the breasts
  • Diabetic mastopathy
  • Diffuse nodular calcifications of breast
  • Finding related to development of the breasts
  • Flat epithelial atypia of breast
  • Galactocele not associated with childbirth
  • Hematoma of left breast
  • Hematoma of right breast
  • Hyperplasia of mammary duct
  • Infarction of breast
  • Jogger's nipple
  • Lactiferous ducts finding
  • Lactocele
  • Nipple deformity
  • Nontraumatic hematoma of left breast
  • Nontraumatic hematoma of right breast
  • Obstruction of milk duct
  • Occlusion of breast duct
  • Occlusion of lactiferous duct of left breast
  • Occlusion of lactiferous duct of right breast
  • Peau d'orange surface of breast
  • Pendulous breast
  • Pendulous left breast
  • Pendulous right breast
  • Post-mastectomy breast deformity
  • Postoperative hematoma of breast
  • Postpartum subinvolution of breast
  • Radial scar of breast
  • Radial scar of left breast
  • Radial scar of right breast
  • Seroma
  • Seroma following procedure
  • Seroma of breast as complication of procedure
  • Skin disorder of breast
  • Subinvolution of breast
  • Thelarche
  • Traumatic hematoma of breast
  • Usual ductal hyperplasia of breast

Tabular List NotesGuidance

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

Inclusion Terms

  • Galactocele
  • Subinvolution of breast (postlactational)

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.

    • Cyst(colloid) (mucous) (simple) (retention)
      • milk
    • Deformity
      • breast (acquired)
    • Deformity
      • nipple (congenital)
        • acquired
    • Degeneration, degenerative
      • breast
    • Degeneration, degenerative
      • nipple
    • Disease, diseased
      • breast
        • specified NEC
    • Disorder(of)
      • breast
        • specified type NEC
    • Galactocele(breast)
    • Hematoma(traumatic) (skin surface intact)
      • breast (nontraumatic)
    • Infarct, infarction
      • breast
    • Mastopathy, mastopathia
      • estrogenic, oestrogenica, oestrogenic
    • Mastopathy, mastopathia
      • ovarian origin
    • Occlusion, occluded
      • mammary duct
    • Pendulous
      • breast
    • Subinvolution
      • breast (postlactational) (postpuerperal)
    • Unilateral
      • development, breast

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR GEN017
Nonmalignant breast conditions
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Seroma

    tumor-like sterile accumulation of serum in a tissue, organ, or cavity. it results from a tissue insult and is the product of tissue inflammation. it most commonly occurs following mastectomy.

  • Mastectomy

    surgical procedure to remove one or both breasts.

  • Grade 1 Seroma, CTCAE|Grade 1 Seroma|Grade 1 Seroma

    symptomatic; simple aspiration indicated

  • Grade 2 Seroma, CTCAE|Grade 2 Seroma|Grade 2 Seroma

    symptomatic, elective invasive intervention indicated

  • Grade 3 Seroma, CTCAE|Grade 3 Seroma|Grade 3 Seroma

    a finding of leakage due to breakdown of an anastomosis (surgical connection of two separate anatomic structures) in the small bowel.

  • Seroma, CTCAE|Seroma|Seroma|Seroma

    asymptomatic; clinical or diagnostic observations only; intervention not indicated

  • Grade 1 Seroma, CTCAE|Grade 1 Seroma|Grade 1 Seroma

    asymptomatic; clinical or diagnostic observations only; intervention not indicated

  • Grade 2 Seroma, CTCAE|Grade 2 Seroma|Grade 2 Seroma

    symptomatic; simple aspiration indicated

  • Grade 3 Seroma, CTCAE|Grade 3 Seroma|Grade 3 Seroma

    symptomatic, elective invasive intervention indicated

  • Seroma

    a collection of serum in the body.

  • Seroma, CTCAE|Seroma|Seroma|Seroma

    a finding of tumor-like collection of serum in the tissues.

Patient EducationClinical

Breast Diseases

Breast diseases include various conditions and changes in your breast. Most women experience breast changes at some time. Your age, hormone levels, and medicines you take may cause lumps, bumps, and discharges of fluids that are not breast milk.

The full article covers:

  • What are breast diseases?
  • What are the symptoms of breast disease?
  • How are breast diseases diagnosed?
  • What are the treatments for breast disease?

Read the full article at MedlinePlus

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

Convert N64.89 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
611.5 Galactocele
Approximate The match is approximate rather than exact.
ICD-9-CM
611.89 Disorders breast NEC
Approximate The match is approximate rather than exact.

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 N64.89Overview

Is N64.89 (Other specified disorders of breast) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other specified disorders of breast on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does N64.89 group to?

When other specified disorders of breast is the principal diagnosis on an inpatient stay, it groups to MS-DRG 600, 601, with relative weights from 0.6050 to 1.0416 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of N64.89?

Under the General Equivalence Mappings, other specified disorders of breast converts to ICD-9-CM 611.5 (galactocele) and 611.89 (disorders breast NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.