ICD-11 classes
02 Neoplasms
Neoplasms of haematopoietic or lymphoid tissues
Myeloproliferative neoplasms
2A21 — Mastocytosis
ICD-11 2A21 — Mastocytosis
Mastocytosis is due to a clonal, neoplastic proliferation of mast cells that accumulate in one or more organ systems. Activating mutations of KIT are frequently found. It is characterised by the presence of multifocal compact clusters or cohesive aggregates/infiltrates of abnormal mast cells. The disorder is heterogeneous, ranging from skin lesions that may spontaneously regress to highly aggressive neoplasms associated with multiorgan failure and short survival. Subtypes of mastocytosis are recognised mainly by the distribution of the disease and clinical manifestations. In cutaneous mastocytosis (CM), the mast cell infiltration remains confined to the skin, whereas systemic mastocytosis (SM) is characterised by involvement of at least one extracutaneous organ with or without evidence of skin lesions. Mastocytosis should be strictly separated from mast cell hyperplasia or mast cell activation states without morphological and/or molecular abnormalities that characterize the neoplastic proliferation.
The diagnosis includes nothing.
The diagnosis excludes nothing.
Diagnosis with code 2A21 contains 6 clarifying diagnoses:
- 2A21.0 — Systemic mastocytosis
It contains 3 clarifying diagnoses. - 2A21.1 — Cutaneous mastocytosis
It contains 2 clarifying diagnoses. - 2A21.2 — Mast cell sarcoma
- 2A21.3 — Extracutaneous mastocytoma
- 2A21.Y — Other specified mastocytosis
- 2A21.Z — Mastocytosis, unspecified
The diagnosis is coded elsewhere:
- Myeloproliferative neoplasms #3186
- Mastocytosis #3206