D47.02
BillableSystemic mastocytosis
HCC Category Mapping
RxHCCHCC 21 — Hodgkin Lymphoma and Other Cancers
0.000What This Code Means
An abnormal growth of mast cells affecting multiple body systems beyond the skin, potentially involving organs like the bone marrow, liver, or spleen.
Coding Tips
- •Ensure documentation specifies systemic involvement beyond cutaneous manifestations
- •Review bone marrow biopsy or other tissue biopsies confirming mast cell infiltration in multiple sites
Clinical Significance
Systemic mastocytosis is a clonal mast cell disorder involving extracutaneous organs, most commonly bone marrow, but also potentially liver, spleen, lymph nodes, and gastrointestinal tract. It can range from indolent disease requiring minimal intervention to aggressive forms with organ damage, and carries risk of anaphylaxis requiring emergency preparedness.
Documentation Requirements
- ✓Documentation must confirm extracutaneous involvement, typically through bone marrow biopsy showing mast cell aggregates, elevated serum tryptase levels, and KIT D816V mutation testing.
- ✓Organ involvement (hepatosplenomegaly, lymphadenopathy, gastrointestinal symptoms) should be documented.
- ✓Classify as indolent, smoldering, or aggressive based on presence of C-findings (organ damage).
Excludes 1 — Do NOT code together
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)
Commonly Confused Codes
D47.01 (cutaneous mastocytosis) is limited to skin involvement without systemic disease.D47.09 (other mast cell neoplasms) covers atypical presentations.C96.20 (malignant mast cell neoplasm) is used for mast cell leukemia or mast cell sarcoma, which are distinct from systemic mastocytosis.C96.A (histiocytic sarcoma) is a different mast cell lineage malignancy.