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This neoplasm is not reportable.
Name
ICD-O-3 Morphology
9741/1: Indolent systemic mastocytosis
Effective
2019 and later
Reportability
This neoplasm is not reportable
Primary Site(s)
No primary site specified
C421
Abstractor Notes
See 9741/3 for cases diagnosed prior to 2019.
To be coded as 9741/3, the diagnosis must be: Aggressive systemic mastocytosis, Systemic mastocytosis with associated clonal hematological non-mast cell lineage disease (SM-AHNMD).
Systemic mastocytosis, NOS (no other information available) is coded to 9741/1 and is not reportable.
To be coded as 9741/3, the diagnosis must be: Aggressive systemic mastocytosis, Systemic mastocytosis with associated clonal hematological non-mast cell lineage disease (SM-AHNMD).
Systemic mastocytosis, NOS (no other information available) is coded to 9741/1 and is not reportable.
Alternate Names
Bone marrow mastocytosis (BMM)
Smoldering systemic mastocytosis (SSM) (2019+, prior to 2019, see 9741/3)
Systemic mastocytosis, NOS (SM)
Definition
In indolent systemic mastocytosis (ISM), the mast cell burden is usually low and skin lesions are found in most patients. For cases that fulfill the criteria for indolent systemic mastocytosis and also present with one B finding, the diagnosis remains indolent systemic mastocytosis. However, if two or more B findings are detected, the diagnosis changes to smoldering systemic mastocytosis.
Bone marrow mastocytosis is a subtype of indolent systemic mastocytosis, the burden of neoplastic mast cells is usually low, and serum tryptase levels are often normal or nearly normal.
Bone marrow mastocytosis is a subtype of indolent systemic mastocytosis, the burden of neoplastic mast cells is usually low, and serum tryptase levels are often normal or nearly normal.
Definitive Diagnostic Methods
This data item does not apply
Immunophenotyping
This data item does not apply
Corresponding ICD-9 Codes
238.5 Neoplasm of uncertain behavior of histiocytic and mast cells
Corresponding ICD-10 Codes
D47.0 Histiocytic and mast cell tumors of uncertain and unknown behavior
Corresponding ICD-10-CM Codes (U.S. only)
D47.02 Systemic mastocytosis (effective October 01, 2015)
Sources
WHO Classification of Tumours Editorial Board. Haematolymphoid tumours. Lyon (France): International Agency for Research on Cancer; 2024. (WHO classification of tumours series, 5th ed.; vol. 11). https://publications.iarc.who.int/637.
Section: Mastocytosis
Pages: Part A: 64-70
Section: Mastocytosis
Pages: Part A: 64-70
International Classification of Diseases for Oncology, 3rd edition (including revisions). Geneva: World Health Organization, 2001, 2011, 2020.
Section: ICD-O-3.2 (2020) Morphological Codes
Pages: http://www.iacr.com.fr/index.php?option=com_content&view=category&layout=blog&id=100&Itemid=577
Section: ICD-O-3.2 (2020) Morphological Codes
Pages: http://www.iacr.com.fr/index.php?option=com_content&view=category&layout=blog&id=100&Itemid=577
