Pathology Outlines - Giant cell tumor of tendon sheath

Soft tissue
Fibrohistiocytic tumors
Giant cell tumor of tendon sheath - diffuse type

Topic Completed: 1 August 2012

Revised: 22 March 2019

Copyright: 2002-2018, PathologyOutlines.com, Inc.

PubMed Search: Giant cell tumor of tendon sheath

See also: Malignant giant cell tumor of tendon sheath - diffuse type

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Table of Contents

Cite this page: Shankar V. Giant cell tumor of tendon sheath - diffuse type. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/softtissuegctdiffuse.html. Accessed October 19th, 2019.

Definition / general

Extra-articular, destructive villonodular hyperplasia with synovial mononuclear cells mixed with multinucleated giant cells, foam cells, siderophages and inflammatory cells
Considered the soft tissue counterpart of pigmented villonodular synovitis - may represent extension of articular tumor since often occurs near a joint

Terminology

Also called tenosynovial giant cell tumor-diffuse type
Called pigmented villonodular synovitis (PVNS) when occurs near a joint
Note: terminology of giant cell tumors is inconsistent in literature

Epidemiology

Rare; less frequent than localized type
Usually < age 40 years, with female predominance

Clinical features

Develops in synovial lining of joints, tendon sheaths and bursae
Usually knee (80%); also ankle, hip, shoulder, elbow, foot
Almost always monoarticular, painful swelling
May actually be hyperplastic, not neoplastic (Hum Pathol 2003;34:65)
Occasionally invades underlying bone; may cause bone cyst formation, loss of bone and cartilage
Locally aggressive; often recurs, but only rarely has malignant behavior (see malignant)

Case reports

26 year old woman with tumor of subcutaneous thigh (Skeletal Radiol 2007;36:327)
Arising in bursa of knee (Knee 2007;14:402)

Treatment

Excision; may recur if inadequate excision; radiation therapy for recurrences
See malignant for cases with malignant behavior

Gross description

Brown-yellow spongy tissue, firm and nodular, often 5 cm or larger

Microscopic (histologic) description

Diffuse expansive sheets of cells with infiltrative borders and variable cellularity; tumor margins are more cellular
Also hyperplastic synovium with papillary projections composed of foamy histiocytes and hemosiderin containing macrophages
Large clefts, pseudoglandular or alveolar spaces lined by synovial cells, osteoclast-like multinucleated (10 - 70 nuclei) giant cells, epithelioid cells
Abundant collagen may be present, but lymphocytes and plasma cells are sparse
Also giant hemosiderotic granules (2 - 3x diameter of RBC), giant siderophages (Pathologe 2005;26:96)
May have 5+ mitotic figures / 10 HPF, rarely chondroid metaplasia (Mod Pathol 2007;20:545)
Malignant if nodular and solid invasive growth plus large cells with large nuclei, prominent nucleoli, necrotic areas and atypical mitotic figures (see malignant)

Microscopic (histologic) images

Images hosted on other servers:

Shoulder tumor

Papillary tumor

Histiocytes and giant cells in dense connective tissue stroma

Iron deposits (Prussian blue stain)

Foam cells

Multiple synovial
lined clefts and
hemosiderin deposits
in the subsynovial layer

Multinucleated giant cells,
synovial cells, fibroblasts
and inflammatory cells

Cytology description

Round, spindled and multinucleated cells without atypia
Round cells have minimal cytoplasm and eccentric nuclei, occasional cytoplasmic hemosiderin, no mitotic figures

Cytology images

Images hosted on other servers:

Various images

Positive stains

CD68 (stromal and giant cells, Hum Pathol 2003;34:65)
Also CD31 (75%), calretinin (63%, Pathologe 2005;26:96), desmin (35 - 40%), CD14
HAM56, CD45, and lysozyme (Arkh Patol 2010;72:34)

Negative stains

S100 (but chondroid areas are S100+), CD45 / LCA, EMA, keratin, HMB45, CD34, smooth muscle actin

Electron microscopy description

Features of histiocytes and fibroblasts (Ultrastruct Pathol 2002;26:15)

Molecular / cytogenetics description

Clonal with neoplastic and reactive features
Neoplastic due to CSF1 overexpression (Am J Surg Pathol 2007;31:970) or 1p13 (CSF1) rearrangements, often with COL6A3 at 2q35 (Proc Natl Acad Sci USA 2006;103:690)
Also reactive features (Hum Pathol 2003;34:65)
Translocations, t(2;3) and der(8) t(8;12) (Ultrastruct Pathol 2002;26:15)
Some show trisomy of chromosome 5 & 7

Differential diagnosis

Hemosiderotic synovitis: associated with hemophilia and intraarticular bleeding, no mononuclear or giant cell nodular proliferation, hemosiderin primarily in synovial lining cells

Additional references

eMedicine #1, #2, Am Fam Physician 1999;60:1404