Interdigitating dendritic cell sarcoma

Interdigitating dendritic cell sarcoma
ICD-O-3 Morphology
9757/3: Interdigitating dendritic cell sarcoma
Effective 2001 and later
for cases diagnosed 2001 and later
Primary Site(s)
See Module 7
Most common sites of involvement: lymph nodes, skin, soft tissue, other extranodal presentations

9 - Grade/differentiation unknown, not stated, or not applicable
Module Rule
Alternate Names
Dendritic cell sarcoma, NOS
IDC sarcoma
Indeterminate dendritic cell tumor
Interdigitating cell sarcoma
IDC sarcoma is a neoplastic proliferation of spindle to ovoid cells with phenotypic features similar to those of interdigitating dendritic cells. Very rare neoplasm with most studies representing single case reports or very small series.

Rare sarcoma arising from the interdigitating reticulum cells in the T-cell area of the lymph node and forming a node-based tumor.

Indeterminate cells are the proposed precursor of Langerhans cells, so this malignancy is in myeloid-derived dendritic cells in contrast to fibroblastic reticular cell tumor (9759/3). These lesions are usually based in the dermis but may extend into the subcutaneous fat. The infiltrate is diffuse, comprising cells resembling Langerhans cells.
Abstractor Notes
Interdigitating dendritic cell sarcoma has shown wide variation.

Visceral organs that are commonly affected include the liver, spleen, kidney and lung. Stage may be an important prognostic factor; however, histological features have not been correlated with clinical outcome.

Indeterminate dendritic cell tumor is a variant of interdigitating dendritic cell sarcoma that should also be coded 9757/3. The clinical course has been highly variable, ranging from spontaneous regression to rapid progression.
Definitive Diagnostic Methods
Genetic testing
Histologic confirmation
Genetics Data
Immunoglobulin heavy chain gene and T-cell receptor beta, delta and gamma chain genes are in germline configuration
CD1a (IDC sarcoma) positive
CD163 (for IDC sarcoma) negative
Fascin (IDC sarcoma) positive
Langerin negative
Myeloperoxidase negative
S100 protein positive
Vimentin (IDC sarcoma) positive
Transformations to
There are no known transformations
Transformations from
There are no known transformations
Same Primaries
Corresponding ICD-9 Codes
202.9 Other and unspecified malignant neoplasms
Corresponding ICD-10 Codes
C96.7 Other specified malignant neoplasms of lymphoid, hematopoietic
Corresponding ICD-10-CM Codes (U.S. only)
C96.4 Sarcoma of dendritic cells (accessory cells) (effective October 01, 2015)
Signs and Symptoms
Drenching night sweats
Generalized lymphadenopathy (rare)
Progression and Transformation
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