Angiomatoid Fibrous Histiocytoma

Definition

Predominantly superficial tumor usually containing cystic blood filled spaces and having a prominent peripheral lymphoid infiltrate

Circumscribed subcutaneous mass
- May have a fibrous capsule
- Rare cases may involve skeletal muscle or periosteum
- Rare cases centered in dermis
Sheets and short fascicles of bland round to short spindled cells
- Usually arranged in nodules
- May have epithelioid, histiocytoid or myoid appearance
- Occasionally contains areas of moderately atypical cells
- Faintly eosinophilic cytoplasm
- Infrequent mitotic figures
- May have occasional foam cells
Large blood filled cystic spaces in most cases
- Lined by lesional round to spindled cells, not by endothelial cells
- May also have dilated endothelial lined vascular spaces
- May thrombose
Marked peripheral lympho-plasmacytic infiltrate
- May form germinal centers
- Present in 80-90% of cases
- May resemble a lymph node, often in a location where there should not be one
  - Lacks subcapsular sinus and hilar lymphatics
90% <30 years of age
Infrequent/rare findings
- Multinucleated cells
- Calcifications
- Marked pleomorphism (no clinical significance)
- Higher mitotic rate >5/10 hpf (no clinical significance)

Richard L Kempson MD
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342

Original posting/updates: 8/10/08, 2/3/10

Translocations involving EWSR1 or FUS and ATF1 or CREB1 reported in most cases tested
- FISH for EWSR1 has been demonstrated to be positive in 74% of cases

Metastatic Mesenchymal Neoplasm in a Lymph Node	Angiomatoid Fibrous Histiocytoma
Typical nodal architecture	Lacks subcapsular sinus and efferent hilar lymphatics
Typical nodal location	Frequently in a site where a lymph node would be unusual
Usually has cytologic atypia	Usually quite bland
Blood filled cystic spaces unusual for most neoplasms	Frequent blood filled cystic spaces

Angiosarcoma	Angiomatoid Fibrous Histiocytoma
Usually dermal	Usually subcutaneous
Usually demonstrates endothelial tufting	Cystic spaces lack endothelial lining
CD31 and CD34 positive in most cases	CD31 and CD34 negative
Desmin negative	Desmin positive in 50% of cases

Kaposi Sarcoma	Angiomatoid Fibrous Histiocytoma
Usually dermal	Usually subcutaneous
Slit-like blood filled spaces	Cystic blood filled spaces
CD31 and CD34 positive in most cases	CD31 and CD34 negative
Desmin negative	Desmin positive in 50% of cases

Aneurysmal (Angiectoid)Benign Dermal Fibrous Histiocytoma	Angiomatoid Fibrous Histiocytoma
Usually dermal	Usually subcutaneous
Lacks fibrous capsule	Usually has fibrous capsule
Lacks surrounding lympho-plasmacytic infiltrate	Usually has prominent lympho-plasmacytic infiltrate
Frequent overlying epidermal hyperplasia	Lacks epidermal hyperplasia
Lacks prominent round cell component	Usually has prominent round cell component
Foam cells and giant cells frequent	Foam cells and giant cells infrequent
Desmin negative	Desmin positive in 50% of cases

Rhabdomyosarcoma	Angiomatoid Fibrous Histiocytoma
Infiltrative	Circumscribed
Lacks surrounding lympho-plasmacytic infiltrate	Usually has prominent lympho-plasmacytic infiltrate
Strap cells and/or rhabdoid cytoplasm	Scant cytoplasm
Blood filled cystic spaces unusual	Frequent blood filled cystic spaces
MyoD1, myoglobin, myogenin positive	MyoD1, myoglobulin, myogenin negative

Diffuse Tenosynovial Giant Cell Tumor	Angiomatoid Fibrous Histiocytoma
Cystic spaces lack blood	Cystic blood filled spaces
Numerous giant cells	Infrequent giant cells
Scant desmin reactivity	May have extensive, strong desmin expression

Vascular Malformation / Hemangioma	Angiomatoid Fibrous Histiocytoma
Cystic spaces lined by endothelium	Cystic spaces not lined by endothelium
Lacks round/spindle cell component	Prominent round/spindle cell component

Inflammatory Myofibroblastic Tumor	Angiomatoid Fibrous Histiocytoma
Blood filled cystic spaces unusual	Frequent blood filled cystic spaces
Inflammatory infiltrate usually contains neutrophils	Neutrophils unusual in infiltrate

Hemangiopericytoma	Angiomatoid Fibrous Histiocytoma
Stag horn vascular spaces lined by endothelium	Cystic spaces not lined by endothelium
CD34 positive 50%	CD34 negative
Desmin negative	Desmin positive 50%

80% localized to subcutaneous tissue
- Up to 20% may involve skeletal muscle or periosteum
- Rare cases in dermis
Mean age 15-20 years
- 90% <30 years
Most common on extremities
Occasional patients with systemic findings
- Anemia, fever, weight loss, lymphadenopathy
- Hypergammaglobulinemia, elevated erythrocyte sedimentation rate
Recurrence rate 10-15%
- Usually only if margins positive
Metastatic rate 1-5%
- Most to local nodes
- Usually curable by excision of involved nodes
- Distant metastases may lead to death

Kempson RL, Fletcher CDM, Evans HL, Henrickson MR, Sibley RS. Tumors of the Soft Tissues, Atlas of Tumor Pathology, AFIP Third Series, Fascicle 30, 2001
Fletcher CDM, Unni KK, Mertens F. Pathology and Genetics of Tumours of Soft Tissue and Bone, World Health Organization Classification of Tumours 2002
Weiss SW, Goldblum JR. Enzinger and Weiss's Soft Tissue Tumors, 5th edition, 2008
Fanburg-Smith JC, Miettinen M. Angiomatoid "malignant" fibrous histiocytoma: a clinicopathologic study of 158 cases and further exploration of the myoid phenotype. Hum Pathol. 1999 Nov;30(11):1336-43.
Thway K. Angiomatoid fibrous histiocytoma: a review with recent genetic findings. Arch Pathol Lab Med. 2008 Feb;132(2):273-7.
Rossi S, Szuhai K, Ijszenga M, Tanke HJ, Zanatta L, Sciot R, Fletcher CD, Dei Tos AP, Hogendoorn PC. EWSR1-CREB1 and EWSR1-ATF1 fusion genes in angiomatoid fibrous histiocytoma. Clin Cancer Res. 2007 Dec 15;13(24):7322-8.
Billings SD, Folpe AL. Cutaneous and subcutaneous fibrohistiocytic tumors of intermediate malignancy: an update. Am J Dermatopathol. 2004 Apr;26(2):141-55.
Tanas MR, Rubin BP, Montgomery EA, Turner SL, Cook JR, Tubbs RR, Billings SD, Goldblum JR. Utility of FISH in the diagnosis of angiomatoid fibrous histiocytoma: a series of 18 cases. Mod Pathol. 2010 Jan;23(1):93-7.

Printed from Surgical Pathology Criteria: http://surgpathcriteria.stanford.edu/


© 2005 Stanford University School of Medicine