2026 ICD-10-CM Diagnosis Code D48.62Neoplasm of uncertain behavior of left breast

ICD-10-CM Codes›C00–D49›D37-D48›D48

ICD-10-CM D48.62
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

D48.62 is a billable ICD-10-CM diagnosis code for neoplasm of uncertain behavior of left breast. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 582 through 583, 597 through 599. Coders also document this condition as bilateral neoplasm of uncertain behavior of breasts. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Neoplasms of unspecified nature or uncertain behavior.

Code Identity

ICD-10-CM Code
D48.62
Billable Status
Yes — Valid for Submission
Code Describes
Neoplasm of uncertain behavior of left breast
Short Description
Neoplasm of uncertain behavior of left breast
Same as the full description in the CMS dataset.
Parent Code
D48.6
Neoplasm of uncertain behavior of breast

Code Classification

ChapterC00–D49Neoplasms
SectionD37-D48Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes
CategoryD48Neoplasm of uncertain behavior of other and unspecified sites
This CodeD48.62Neoplasm of uncertain behavior of left breast

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bilateral neoplasm of uncertain behavior of breasts
  • Borderline phyllodes neoplasm of left breast
  • Neoplasm of uncertain behavior of left breast
  • Neoplasm of uncertain behavior of right breast
  • Phyllodes tumor of breast
  • Phyllodes tumor of breast, borderline

Clinical ClassificationClinical

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

CCSR NEO072
Neoplasms of unspecified nature or uncertain behavior
Default principal diagnosis: inpatient Yes · outpatient Yes

Table of NeoplasmsClinical

Anatomical sites in the Table of Neoplasms that reference this code family.

SiteMalig.
Primary		Malig.
Secondary		Ca
in situ		BenignUncertainUnspec.
areolaC50.0C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts)C50.9C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › areolaC50.0C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › axillary tailC50.6C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › central portionC50.1C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › innerC50.8C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › lowerC50.8C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › lower-inner quadrantC50.3C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › lower-outer quadrantC50.5C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › midlineC50.8C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › nippleC50.0C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › outerC50.8C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › tail (axillary)C50.6C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › upperC50.8C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › upper-inner quadrantC50.2C79.81D05.D24.D48.6D49.3
breast (connective tissue) (glandular tissue) (soft parts) › upper-outer quadrantC50.4C79.81D05.D24.D48.6D49.3

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 D48.62 to ICD-9-CMHistory

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

ICD-9-CM
238.3 Unc behav neo breast
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 D48.62Overview

Is D48.62 (Neoplasm of uncertain behavior of breast) a billable code?

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

What MS-DRG does D48.62 group to?

When neoplasm of uncertain behavior of left breast is the principal diagnosis on an inpatient stay, it groups to MS-DRG 582, 583, 597, 598, 599, with relative weights from 0.7332 to 1.9266 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of D48.62?

Under the General Equivalence Mappings, neoplasm of uncertain behavior of left breast converts to ICD-9-CM 238.3 (unc behav neo breast). 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.