Follicular dendritic cell sarcoma

ICD-O-3 Morphology

9758/3: Follicular 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 (primarily cervical), tonsil, oral cavity, GI tract, soft tissue, skin, mediastinum, liver, and spleen.

Abstractor Notes

This is an indolent sarcoma, much like a low or intermediate-grade soft tissue sarcoma. Cases showing high-grade features (significant cytologic atypia, extensive coagulative necrosis, and a high proliferative index), large tumor size (greater than 6 cm), or intra-abdominal location can pursue a rapidly fatal course.

Systemic symptoms are uncommon in conventional follicular dendritic cell sarcoma, but are common in the inflammatory pseudo-tumor-like variant.

Most patients are treated by complete surgical excision, with or without adjuvant radiotherapy or chemotherapy.

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.


Not Applicable

Module Rule


Alternate Names

Dendritic reticulum cell sarcoma
FDC sarcoma
Follicular dendritic cell tumor
Inflammatory pseudotumour-like follicular/fibroblastic dendritic cell sarcoma
Sarcoma of follicular dendritic cells


Follicular dendritic cell (FDC) sarcoma is a neoplastic proliferation of spindled to ovoid cells showing morphological and immunophenotypic features of FDCs.

Definitive Diagnostic Methods

Genetic testing
Histologic confirmation

Genetics Data

Immunoglobulin and T-cell receptor genes in germline configuration


CD3 negative
CD21 positive
CD23 positive
CD34 negative
CD35 positive
CD79a negative
Clusterin strongly positive
CXCL13 positive
Desmoplakin positive
Epidermal growth factor receptor (EGFR) positive
Fascin positive
HLA-DR positive
HMB45 negative
Lysozyme negative
MPO negative
Vimentin positive


Radiation therapy

Transformations to

There are no known transformations

Transformations from

There are no known transformations

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

Abdominal pain (due to abdominal disease)
Drenching night sweats (inflammatory pseudo-tumor-like variant)
Fatigue (inflammatory pseudo-tumor-like variant)
Fever (inflammatory pseudo-tumor-like variant)
Paraneoplastic pemphigus (rare)
Slow growing painless mass

Diagnostic Exams

Blood chemistry studies
Bone scan
BRAF testing
CT (CAT) scan
Flow cytometry
Liver function test
Neurological exam
PET (positron emission tomography) scan
Ultrasound exam
Water deprivation test

Progression and Transformation

Local recurrences occur in more than 50% of cases
Metastases occurs in ~25% of cases

Epidemiology and Mortality

Age: 44 years median age (wide age range)
Incidence: rare disease
Sex: no male or female predominance
Survival: 10-20% of patients die from disease after long period of time


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: Histiocytic and dendritic cell neoplasms
Pages: 476-479

International Classification of Diseases for Oncology, Third Edition, Second Revision. Geneva: World Health Organization, 2020.
Section: ICD-O-3.2 (2020) Morphological Codes

National Cancer Institute
Section: General Information About Langerhans Cell Histiocytosis (LCH)