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C50.A ICD-10-CM Code: Malignant inflammatory neoplasm of breast

Compare with another code for C50.ACheck this code on a claim

Billing Status: NO. This is a non-billable ICD-10-CM code: report a more specific billable code beneath it.

Coding at a Glance

Tabular directives
4 inclusion terms · 1 Excludes1 · 1 use-additional code

Not billable · FY2027A non-billable heading in the tabular list: report a more specific code beneath it.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too, and is marked with where it comes from.

Use additional codefrom C50Report with this code when documented
  • Use additional code to identify estrogen, and other hormones and factors receptor status (Z17.-)
Excludes1from C50Not reported with this code unless documented as unrelated
IncludesWhat this code covers
  • connective tissue of breast (from C50)
  • Paget's disease of breast (from C50)
  • Paget's disease of nipple (from C50)
  • Inflammatory breast cancer (IBC)

Where it sits Source: CMS/NCHS

Under:Chapter 2: NeoplasmsC00-C96 Malignant neoplasmsC00-C75 Malignant neoplasms, stated or presumed to be primary (of specified sites), and certain specified histologies, except neuroendocrine, and of lymphoid, hematopoietic and related tissueC50 Malignant neoplasm of breast

Codes under C50.A (3)

  • C50.A0Malignant inflammatory neoplasm of unspecified breastBillable
  • C50.A1Malignant inflammatory neoplasm of right breastBillable
  • C50.A2Malignant inflammatory neoplasm of left breastBillable

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

CompareCheck ClaimView Related Codes

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for C50.A in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on C50.A itself; “inherited from” names the category or block whose note applies here.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • connective tissue of breast
  • Paget's disease of breast
  • Paget's disease of nipple

Source: inherited from C50

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Inflammatory breast cancer (IBC)

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Source: inherited from C50

Use Additional Code

Supplementary codes the tabular list directs you to add.

  • Use additional code to identify estrogen, and other hormones and factors receptor status (Z17.-)

Source: inherited from C50

Coder workflow for C50.A

MedCoder structured workflow — derived from this code’s own official record

Before you code C50.A

  1. C50.A is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).

    ReviewC50.A0, C50.A1

    See the relationships section · Guide: How to choose an ICD-10-CM code →

  2. Confirm the documented site and behavior (this code’s block classifies malignant neoplasms), whether the site is primary or secondary, and whether the malignancy is current or a personal history: a previously excised malignancy with no further treatment and no evidence of disease is history, not current disease. Verify the site against the Table of Neoplasms. Neoplasm chapter guidelines (Guidelines I.C.2.a, I.C.2.d, I.C.2.m).

    See the Table of Neoplasms entries · Guide: Active cancer vs history of cancer →

  3. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with the code beneath C50.A. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support one of the more specific codes beneath C50.A?
    Yes → Select that code and continue the checks below on its own page.
    No → C50.A cannot be reported as written. Where the codes beneath it include an unspecified code, that code applies when the record goes no further; otherwise query for the missing detail.

    ReviewC50.A0, C50.A1

  2. Does the documentation support a condition named in C50.A’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

    ReviewC44.501, C44.511, C44.521, C44.591

Report the code beneath C50.A that the documentation supports, not C50.A itself. Then work the Use Additional Code note, and confirm that code is valid for the date of service on its own page.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Anatomical site
At the most specific level the record states; a site the classification separates cannot be assumed from a procedure or a measurement.
The conditions the Use Additional Code note names
Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.
Behavior and current-versus-history status
Malignant, in situ, benign or uncertain; primary or secondary; current disease or personal history (Guidelines I.C.2.m).

Official instructions as workflow

  • Excludes1 — check before selecting C50.A(1 note)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with C50.A: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareC44.501, C44.511, C44.521, C44.591

    See the official tabular notes · Guidelines I.A.12.a

  • Use Additional Code — after identifying C50.A(1 note)

    Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with C50.A when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.

    ReviewZ17

    See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: Both the condition C50.A describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewC44.501, C44.511, C44.521, C44.591

Documentation: A condition the Use Additional Code note names is documented.

Coding question: Is a second code reported with the code beneath C50.A?

Path: Review the Use Additional Code note and the code it names.

Reason: The additional code is reported when the record documents the condition; a conditional instruction applies only when its condition is met (Guidelines I.A.13).

ReviewZ17

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Don’t confuse C50.A with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of C50.A — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

  • C44.501— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of skin of breast moves the case to C44.501; the two are not reported together unless documented as unrelated.

    Full comparison: C50.A vs C44.501 →

  • C44.511— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of skin of breast moves the case to C44.511; the two are not reported together unless documented as unrelated.

    Full comparison: C50.A vs C44.511 →

  • C44.521— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of skin of breast moves the case to C44.521; the two are not reported together unless documented as unrelated.

    Full comparison: C50.A vs C44.521 →

  • C44.591— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of skin of breast moves the case to C44.591; the two are not reported together unless documented as unrelated.

    Full comparison: C50.A vs C44.591 →

  • C50.9— Specificity relationship (Review)

    Overlapping diagnoses in the same category.

    Overlapping codes in the same category — the documentation decides which is the more specific fit.

    What moves you there: A record that documents no more than “Malignant neoplasm of breast of unspecified site” takes C50.9; specificity in the record moves it back here.

    Full comparison: C50.A vs C50.9 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Malignant inflammatory neoplasm of breast is a non-billable ICD-10-CM category code (C50.A). A more specific billable subcode must be selected for claims submission.

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Verify Before Coding

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name C50.A or its code family, from the CMS ICD-10-CM tabular instructional notes and the CMS Table of Neoplasms (site match derived from the code title). Tabular-note edges are stored at the code family level that carries each note.

Referenced by 4 Excludes1 notes across 2 chapters: C49 — Malignant neoplasm of other connective and soft tissue (via C50.-), C49.3 — Malignant neoplasm of connective and soft tissue of thorax (via C50.-), D05 — Carcinoma in situ of breast (via C50.-), N61 — Inflammatory disorders of breast.

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 3 Code First instructions across 2 chapters: D75.81 — Myelofibrosis (via C50.-), Z17 — Estrogen, and other hormones and factors receptor status (via C50.-), Z79.81 — Long term (current) use of agents affecting estrogen receptors and estrogen levels (via C50.-).

Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.

Referenced by 1 Code Also instruction: D61.82 — Myelophthisis (via C50.-).

These codes suggest coding this condition alongside when both are present.

Referenced by 5 Screening & history codes: Z12.3 — Encounter for screening for malignant neoplasm of breastCompare C50.A vs Z12.3 →, Z12.31 — Encounter for screening mammogram for malignant neoplasm of breastCompare C50.A vs Z12.31 →, Z12.39 — Encounter for other screening for malignant neoplasm of breastCompare C50.A vs Z12.39 →, Z80.3 — Family history of malignant neoplasm of breastCompare C50.A vs Z80.3 →, Z85.3 — Personal history of malignant neoplasm of breastCompare C50.A vs Z85.3 →.

These codes represent screening tests and history codes that refer to this active disease condition.

Contextual Map

Every relationship of C50.A in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run C50.A with these 8 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes

Referenced by Code First instructions

Referenced by Code Also instructions

  • D61.82 — Myelophthisis[Code Also](via C50.-): “malignant neoplasm of breast (C50.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2027

Referenced by Screening & history codes MedCoder-derived

Neoplasm sites

  • Neoplasm, neoplastic, breast (connective tissue) (glandular tissue) (soft parts), inflammatory — Neoplasm, neoplastic, breast (connective tissue) (glandular tissue) (soft parts), inflammatory — Malignant, Primary [Neoplasm table]: “Neoplasm, neoplastic, breast (connective tissue) (glandular tissue) (soft parts), inflammatory (Malignant, Primary)”— CMS Table of Neoplasms · icd10cm-fy2027

Nearest codes (40)

Change history

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Neoplasm Table Sites (1)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Anatomical sites from the official ICD-10-CM Table of Neoplasms that map to this code, with the matching behavior column.

  • Neoplasm, neoplastic, breast (connective tissue) (glandular tissue) (soft parts), inflammatory — Malignant, Primary

Common coding questions

MedCoder editorial

Can C50.A be billed directly?

No. C50.A (Malignant inflammatory neoplasm of breast) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder-derived relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder editorial explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "C50.A — Malignant inflammatory neoplasm of breast." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/c50.a-malignant-inflammatory-neoplasm-of-breast

Change history

  • FY2026 — October 1, 2025
    Added to the code set
    Malignant inflammatory neoplasm of breast
    FY2026 changes

Nearest Codes in This Family

Official ICD-10-CM classifications closest to C50.A in its code family, with their registry titles.

View all codes in the C50 family