Search Database ICD-O-3 Code Lists

Name

Histiocytic sarcoma

ICD-O-3 Morphology

9755/3: Histiocytic sarcoma
Effective 2001 and later

Reportable

for cases diagnosed 1978 and later

Primary Site(s)

See Module 7
Most common sites of involvement: lymph nodes, skin, intestinal tract, soft tissue

See abstractor notes

Coding Manual: Hematopoietic Coding Manual (PDF)

Abstractor Notes

Histiocytic sarcoma is part of the Histiocyte/macrophage neoplasms lineage table in the WHO 5th edition of Hematolymphoid Tumors. (See Appendix B in the Hematopoietic Manual, Table B12)

HS occurs in lymph nodes or in extranodal sites, most commonly the gastrointestinal tract, spleen, soft tissue, skin, and CNS.

It can be localized or disseminated.

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.

Module Rule

None

Alternate Names

Monocytic sarcoma
True histiocytic lymphoma/sarcoma

Definition

Histiocytic sarcoma (HS) is a malignant tumor showing morphological and immunophenotypic features of macrophages. Tumorous proliferations of acute monocytic leukemia are excluded. (WHO 5th edition)

Definitive Diagnostic Methods

Cytogenetics
Genetic testing
Histologic confirmation
Immunohistochemistry
Immunophenotyping

Genetics Data

MAPK pathway genes (KRAS, NRAS, BRAF, MAP2K1, PTPN11, NF1, CBL)
Mutations in tumor suppressors such as CDKN2A and TP53

Immunophenotyping

CD4+ (expression/positive)
CD45+ (expression/positive)
CD45RO+ (expression/positive)
CD68+ (expression/positive)
CD163+ (expression/positive)
Lysozyme+ (expression/positive)
PU.1+ (expression/positive)

Treatments

Chemotherapy
Hematologic Transplant and/or Endocrine Procedures
Hormone therapy
Radiation therapy
Surgery

Transformations to

There are no known transformations

Transformations from

There are no known transformations

Same Primaries

Corresponding ICD-10 Codes (Cause of Death codes only)

C96.3 True histiocytic lymphoma

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

C96.A Histiocytic sarcoma (effective October 01, 2015)

Signs and Symptoms

Fever
Hepatosplenomegaly
Lymphadenopathy
Lytic lesions on bones
Pancytopenia
Skin lesions (solitary and innumerable)
Weight loss

Diagnostic Exams

Biopsy
Blood chemistry studies
Bone marrow aspiration and biopsy
Bone scan
BRAF testing
CT (CAT) scan
Endoscopy
Flow cytometry
Immunophenotyping
Liver function test
Neurological exam
PET (positron emission tomography) scan
Ultrasound exam
Urinalysis
Water deprivation test

Progression and Transformation

Most patients die of progressive involvement reflecting the high clinical stage at presentation (stage III-IV) in the majority of patients

Epidemiology and Mortality

Age: 52 years median age (infancy to elderly age range)
Incidence: rare, limited number of reported cases
Sex: male predominance
Survival: generally poor, 60-80% of patients die from progressive involvement

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: Histiocytic/dendritic cell neoplasms
Pages: Part A: 255-257

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
Glossary