Name

Mast cell sarcoma

ICD-O-1 Morphology

9740/3: Mast cell sarcoma
Effective 1978 - 1991

ICD-O-2 Morphology

9740/3: Mast cell sarcoma
Effective 1992 - 2000

ICD-O-3 Morphology

9740/3: Mast cell sarcoma
Effective 2001 and later

Reportable

for cases diagnosed 1978 and later

Primary Site(s)

See Module 7
Most common sites of involvement: larynx, large bowel, meninges, bone and skin.

Abstractor Notes

If Mast cell sarcoma occurs simultaneously or after Mast cell leukemia, see M3 and Module 5:PH 9.

Diagnostic Confirmation

This histology can be determined by positive histology (including peripheral blood) with or without genetics and/or immunophenotyping. Review the Definitive Diagnostic Methods, Immunophenotyping and Genetics Data sections below, and the instructions in the Hematopoietic Manual for further guidance on assigning Diagnostic confirmation.

Grade

Not Applicable

Module Rule

None

Alternate Names

Malignant mast cell tumor
Malignant mastocytoma
MCS

Definition

Mast cell sarcoma (MCS) is an extremely rare entity characterized by localized destructive growth of highly atypical mast cells, which can be identified only through the application of appropriate immunohistochemical markers, such as antibodies specific for tryptase and KIT (CD117).

Although the disease is initially localized, distant spread followed by a terminal phase resembling mast cell leukemia occurs after a short interval of several months.

Definitive Diagnostic Methods

Bone marrow biopsy
Genetic testing
Immunophenotyping

Genetics Data

None

Immunophenotyping

Immunohistochemical markers anti-tryptase/chymase and anti-CD117
KIT (CD117)+ (expression/positive)

Treatments

Chemotherapy
Radiation therapy
Surgery

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)

C96.22 Mast cell sarcoma (effective October 01, 2015)
C96.20 Malignant mast cell neoplasm, unspecified (effective October 01, 2015)

Signs and Symptoms

Abdominal pain
Arthralgias
Bone pain
Dermatographism
Diaphoresis
Fatigue
Fever
Flushing
Fractures
Gastrointestinal distress
Headache
Hepatosplenomegaly
Hypotension
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

Mast cell sarcoma is initially localized, followed within months by distant spread and terminal phase.

Epidemiology and Mortality

Survival: aggressive course, death within 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, Second Revision. Geneva: World Health Organization, 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
Glossary