Search Database ICD-O-3 Code Lists

Name

Interdigitating dendritic cell sarcoma (IDCS)

ICD-O-3 Morphology

9757/3: Interdigitating dendritic cell sarcoma
Effective 2001 and later

Reportable

for cases diagnosed 1978 and later

Primary Site(s)

See Module 7
Most common sites of involvement: skin, bone, spleen, lung, thyroid, parotid, and lymph node.

See abstractor notes

Coding Manual: Hematopoietic Coding Manual (PDF)

Abstractor Notes

Interdigitating dendritic cell sarcoma (IDCS) is part of the Langerhans cell and other dendritic cell neoplasms lineage table in the WHO 5th edition of Hematolymphoid Tumors. (See Appendix B in the Hematopoietic Manual, Table B11)

DCT is usually a skin-limited disorder manifesting with single, multifocal, or generalized papules and/or nodules

Generalized skin eruption is the most common clinical presentation; solitary lesions often involve the arms or scalp. Extracutaneous involvement has been reported to occur in bone, spleen, lung, thyroid, parotid, and lymph node.

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

Dendritic cell sarcoma (tumor), NOS
Indeterminate cell histiocytosis
Indeterminate dendritic cell tumor
Interdigitating cell sarcoma (IDC)

Definition

Indeterminate dendritic cell tumor (IDCT) is a clonal proliferation of histiocytes expressing dendritic cell markers (CD1a, S100) and lacking CD207 (langerin). (WHO 5th edition).

Definitive Diagnostic Methods

Cytogenetics
Genetic testing
Histologic confirmation
Immunohistochemistry
Immunophenotyping

Genetics Data

BRAF p.V600E mutations
KMT2A (MLL) mutations
KRAS (p.G12R) mutations

Immunophenotyping

CD1a+ (expression/positive)
CD207 (langerin)- (no expression/negative)
S100 protein+ (expression/positive)

Treatments

Chemotherapy
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)

C96.7 Other specified malignant neoplasms of lymphoid, hematopoietic, and related tissue
C96.9 Malignant neoplasms of lymphoid, hematopoietic, and related tissue, unspecified

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

C96.4 Sarcoma of dendritic cells (accessory cells) (effective October 01, 2015)

Signs and Symptoms

Asymptomatic mass
Drenching night sweats
Fatigue
Fever
Generalized lymphadenopathy (rare)

Diagnostic Exams

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

Progression and Transformation

None

Epidemiology and Mortality

Age: predominantly adults
Incidence: very rare disease
Sex: slight male predominance
Survival: aggressive lymphoma, poor survival, ~1/2 of patients die of disease

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: 237-241

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

PDQ® Pediatric Treatment Editorial Board. PDQ Langerhans Cell Histiocytosis Treatment. Bethesda, MD: National Cancer Institute. Updated <01/06/2025>. Available at: https://www.cancer.gov/types/langerhans/hp/langerhans-treatment-pdq. Accessed <02/28/2025>. [PMID: 26389240]
Section: Langerhans Cell Histiocytosis Treatment (PDQ®)–Health Professional Version
Pages: https://www.cancer.gov/types/langerhans/hp/langerhans-treatment-pdq#section/_178%20or%20http://www.cancer.gov/types/langerhans/patient/langerhans-treatment-pdq
Glossary