2027 ICD-10-CM Diagnosis Code N60.99Unspecified benign mammary dysplasia of unspecified breast

ICD-10-CM Codes›N00–N99›N60-N65›N60

ICD-10-CM N60.99
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

N60.99 is a billable ICD-10-CM diagnosis code for unspecified benign mammary dysplasia of unspecified breast. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 600 through 601. Coders also document this condition as benign mammary dysplasia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nonmalignant breast conditions.

Code Identity

ICD-10-CM Code
N60.99
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified benign mammary dysplasia of unspecified breast
Short Description
Unspecified benign mammary dysplasia of unspecified breast
Same as the full description in the CMS dataset.
Parent Code
N60.9
Unspecified benign mammary dysplasia

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN60-N65Disorders of breast
CategoryN60Benign mammary dysplasia
This CodeN60.99Unspecified benign mammary dysplasia of unspecified breast

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Benign mammary dysplasia
  • Hyperplasia of mammary duct

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to N60.99: its own notes plus those printed at N60, block N60-N65, and Chapter 14. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From N60 Benign mammary dysplasia applies to 21 codes
  • fibrocystic mastopathy

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Block N60-N65 Disorders of breast applies to 60 codes
  • disorders of breast associated with childbirth (O91-O92)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 14 (N00-N99) Diseases of the genitourinary system applies to 838 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name N60.99, its category, or a range that includes it.

Excludes2 3

These codes carry an Excludes2 note naming N60.99: its condition is not part of those codes, and both may be reported when the patient has both.

  • D24 Benign neoplasm of breast
    benign cyst of breast (N60.-) names N60.-, which includes this code
  • D24 Benign neoplasm of breast
    benign mammary dysplasia (N60.-) names N60.-, which includes this code
  • D24 Benign neoplasm of breast
    fibrocystic disease of breast (N60.-) names N60.-, which includes this code

Clinical ClassificationClinical

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

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

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 N60.99 to ICD-9-CMHistory

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

ICD-9-CM
610.9 Benign mamm dysplas NOS
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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About N60.99Overview

What is the ICD-10 code for unspecified benign mammary dysplasia of unspecified breast?

The ICD-10-CM code for unspecified benign mammary dysplasia of unspecified breast is N60.99 (sometimes written as N6099). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is N60.99 (Unspecified benign mammary dysplasia) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified benign mammary dysplasia of unspecified breast on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does N60.99 group to?

When unspecified benign mammary dysplasia of unspecified breast is the principal diagnosis on an inpatient stay, it groups to MS-DRG 600, 601, with relative weights from 0.6014 to 0.9971 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of N60.99?

Under the General Equivalence Mappings, unspecified benign mammary dysplasia of unspecified breast converts to ICD-9-CM 610.9 (benign mamm dysplas NOS). The mapping is approximate, so confirm the match fits the documentation.