2026 ICD-10-CM Diagnosis Code D47.02Systemic mastocytosis

ICD-10-CM Codes›C00–D49›D37-D48›D47

ICD-10-CM D47.02
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

D47.02 is a billable ICD-10-CM diagnosis code for systemic mastocytosis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 820 through 825, 840 through 842. Coders also document this condition as indolent systemic mastocytosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Neoplasms of unspecified nature or uncertain behavior.

Code Identity

ICD-10-CM Code
D47.02
Billable Status
Yes — Valid for Submission
Code Describes
Systemic mastocytosis
Short Description
Systemic mastocytosis
Same as the full description in the CMS dataset.
Parent Code
D47.0
Mast cell neoplasms of uncertain behavior

Code Classification

ChapterC00–D49Neoplasms
SectionD37-D48Neoplasms of uncertain behavior, polycythemia vera and myelodysplastic syndromes
CategoryD47Other neoplasms of uncertain behavior of lymphoid, hematopoietic and related tissue
This CodeD47.02Systemic mastocytosis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Indolent systemic mastocytosis
  • Isolated bone marrow mastocytosis
  • Malignant mastocytosis
  • Smoldering systemic mastocytosis
  • Systemic mast cell disease
  • Systemic mastocytosis with associated clonal hematological non-mast cell lineage disease

Tabular List NotesGuidance

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

Inclusion Terms

  • Indolent systemic mastocytosis
  • Isolated bone marrow mastocytosis
  • Smoldering systemic mastocytosis
  • Systemic mastocytosis, with an associated hematological non-mast cell lineage disease (SM-AHNMD)

Code Also

  • , if applicable, any associated hematological non-mast cell lineage disease, such as:
  • acute myeloid leukemia C92.6 C92.A
  • chronic myelomonocytic leukemia C93.1
  • essential thrombocytosis D47.3
  • hypereosinophilic syndrome D72.1
  • myelodysplastic syndrome D46.9
  • myeloproliferative syndrome D47.1
  • non-Hodgkin lymphoma C82 C85
  • plasma cell myeloma C90.0
  • polycythemia vera D45

Type 1 Excludes

  • aggressive systemic mastocytosis C96.21
  • mast cell leukemia C94.3

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.

    • Disease, diseased
      • systemic tissue mast cell
    • Mast cell
      • disease, systemic tissue
    • Mastocytosis
      • indolent systemic
    • Mastocytosis
      • isolated bone marrow
    • Mastocytosis
      • systemic (indolent) (smoldering)
        • with an associated hematological non-mast cell lineage disease (SM-AHNMD)

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

Clinical InformationClinical

  • Smoldering Systemic Mastocytosis

    slowly progressive systemic mastocytosis with uncertain prognosis. it is characterized by organomegaly and absence of aggressive disease.

  • Smoldering Systemic Mastocytosis with an Associated Myeloid Neoplasm|Smoldering Systemic Mastocytosis with an Associated Hematologic Neoplasm

    smoldering systemic mastocytosis associated with the presence of a clonal non-mast cell myeloid neoplasm (e.g., myelodysplastic syndrome, myeloproliferative neoplasm, and acute myeloid leukemia).

Patient EducationClinical

Systemic mastocytosis

Systemic mastocytosis is a blood disorder that can affect many different body systems. Individuals with the condition can develop signs and symptoms at any age, but it usually appears after adolescence.

Read the full article at MedlinePlus

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

Convert D47.02 to ICD-9-CMHistory

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

ICD-9-CM
238.5 Mastocytoma NOS
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement D47.02 replaces the following previously assigned code(s):

  • D47.0 - Histiocytic and mast cell tumors of uncertain behavior
  • D47.0 - Mast cell neoplasms of uncertain behavior
FY 2018AddedAdded to the ICD-10-CM code setEffective October 1, 2017.
FY 2019–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About D47.02Overview

Is D47.02 (Mast cell neoplasms of uncertain behavior) a billable code?

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

What MS-DRG does D47.02 group to?

When systemic mastocytosis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 820, 821, 822, 823, 824, 825, 840, 841, 842, with relative weights from 1.0104 to 5.8648 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of D47.02?

Under the General Equivalence Mappings, systemic mastocytosis converts to ICD-9-CM 238.5 (mastocytoma NOS). 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.