Name

Systemic mastocytosis with an associated hematological neoplasm

ICD-O-1 Morphology

9741/3: Malignant mastocytosis
Effective 1978 - 1991

ICD-O-2 Morphology

9741/3: Malignant mastocytosis
Effective 1992 - 2000

ICD-O-3 Morphology

9741/3: Malignant mastocytosis
Effective 2001 and later

Reportable

for cases diagnosed 1978 and later

Primary Site(s)

C421
Primary site must be bone marrow (C421)

Grade

Not Applicable

Module Rule

None

Alternate Names

Aggressive systemic mastocytosis
AHN
ASM
Lymphadenopathic (systemic) mastocytosis with eosinophilia
Malignant mastocytosis
SM
SM-AHNMD
Smoldering systemic mastocytosis
Systemic mastocytosis, NOS
Systemic mastocytosis with an associated hematological neoplasm (AHN)
Systemic mastocytosis with associated clonal hematological non-mast cell lineage disease
Systemic mastocytosis with AHNMD
Systemic tissue mast cell disease

Definition

Criteria for the diagnosis of systemic mastocytosis have been established. Five variants are recognized.

Smoldering systemic mastocytosis: The mast cell burden is high, organomegaly is often found, and multilineage involvement is typically present. The clinical course is usually stable for many years, but there may be progression to aggressive systemic mastocytosis or mast cell leukemia. Skin lesions are found in most patients.

Systemic mastocytosis with an associated hematological neoplasm (AHN): This fulfills the general criteria for systemic mastocytosis as well as the criteria for an AHN. In most cases, a myeloid disease of non-mast cell lineage is detected, such as a myelodysplastic syndrome, myeloproliferative neoplasm, myelodysplastic/myeloproliferative neoplasm or acute leukemia.

The AHN should be abstracted as a second primary.

Aggressive systemic mastocytosis (ASM): Mast cells in bone marrow smears may be increased in number, but account for less than 20% of all nucleated bone marrow cells. Most patients with ASM have no skin lesions.

Indolent systemic mastocytosis. See 9741/1.

Bone marrow mastocytosis. See 9741/1.

Abstractor Notes

If the diagnosis is "systemic mastocytosis with an associated hematological neoplasm (AHN)" the patient has a history of myelodysplastic syndrome, myeloproliferative neoplasm, myelodysplastic/myeloproliferative neoplasm or acute leukemia. This would be a second primary.

Smoldering systemic mastocytosis may progress to aggressive systemic mastocytosis (ASM) or mast cell leukemia. Progression to either of these neoplasms is the same primary.

Definitive Diagnostic Methods

Bone marrow biopsy
Genetic testing
Histologic confirmation

Genetics Data

KIT D816V

Immunophenotyping

None

Treatments

Chemotherapy
Immunotherapy

Transformations to

There are no known transformations

Transformations from

There are no known transformations

Corresponding ICD-9 Codes

202.6 Malignant mast cell tumors

Corresponding ICD-10 Codes

C96.2 Malignant mast cell tumor

Corresponding ICD-10-CM Codes (U.S. only)

C96.21 Aggressive systemic mastocytosis (effective October 01, 2015)
D47.02 Systemic mastocytosis (effective October 01, 2015)

Signs and Symptoms

Abdominal pain
Anemia
Arthralgias
Bone pain
Dermatographism
Diaphoresis
Eosinophilia
Fatigue
Fever
Flushing
Fractures
Gastrointestinal distress
Headache
Hepatosplenomegaly
Hypotension
Leukocytosis
Myalgias
Neutropenia
Osteopenia/osteoporosis
Pruritis
Respiratory problems
Syncope
Tachycardia
Thrombocytopenia
Urticaria
Weight loss

Diagnostic Exams

Blood chemistry studies
CT (CAT) scan
Peripheral blood smear
Skeletal survey
Skin biopsy

Progression and Transformation

None

Epidemiology and Mortality

Age: primary second decade of life
Sex: no male or female predominance
Survival: patients with cutaneous involvement only follow indolent course and may have a normal life expectancy. Patients with no skin lesions and aggressive disease may survive only a few months

Sources

Swerdlow SH, Campo E, Harris NL, Jaffe ES, Pileri SA, Stein H, Thiele J (Eds):
WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues (Revised 4th edition)
IARC: Lyon 2017
Section: Mastocytosis
Pages: 69

International Classification of Diseases for Oncology, Third Edition, First Revision. Geneva: World Health Organization, 2013.
Section: ICD-O-3.1 (2011) Morphological Codes
Pages: http://codes.iarc.fr/codegroup/2
Glossary