2026 ICD-10-CM Diagnosis Code S20.159ASuperficial foreign body of breast, unspecified breast, initial encounter
S20.159A is a billable ICD-10-CM diagnosis code for superficial foreign body of breast, unspecified breast, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 604 through 605, 963 through 965. Coders also document this condition as foreign body in skin of breast. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Superficial injury; contusion, initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Foreign body in skin of breast
- Foreign body in skin of breast with infection
- Foreign body in skin of chest
- Foreign body of breast
- Splinter in breast
- Splinter in breast with infection
- Superficial foreign body of chest wall with infection
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Superficial injury of thorax (S20). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Foreign Bodies
If you've ever gotten a splinter or had sand in your eye, you've had experience with a foreign body. A foreign body is something that is stuck inside you but isn't supposed to be there. You may inhale or swallow a foreign body, or you may get one from an injury to almost any part of your body.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert S20.159A to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S20.159AOverview
Is S20.159A (Superficial foreign body of breast, unspecified breast) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report superficial foreign body of breast, unspecified breast, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in S20.159A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for superficial foreign body of breast, unspecified breast, such as an emergency visit or first evaluation.
What MS-DRG does S20.159A group to?
When superficial foreign body of breast, unspecified breast, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 604, 605, 963, 964, 965, with relative weights from 0.9160 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of S20.159A?
Under the General Equivalence Mappings, superficial foreign body of breast, unspecified breast, initial encounter converts to ICD-9-CM 911.6 (foreign body trunk). 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.
