Joint tumors
Pigmented villonodular synovitis (PVNS)

Topic Completed: 1 June 2013

Minor changes: 30 September 2019

Copyright: 2002-2019,, Inc.

PubMed Search: Pigmented villonodular synovitis joints "loattrfree full text"[sb]

Vijay Shankar, M.D.
Page views in 2019: 20,234
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Cite this page: Shankar V. Pigmented villonodular synovitis (PVNS). website. Accessed May 30th, 2020.
Definition / general
Clinical features
  • Develops in synovial lining of joints, tendon sheaths and bursae, usually of knee (80%), ankle, hip, shoulder, elbow joint; nodular variant occurs in hands and wrists
  • Almost always monoarticular
  • Occasionally invades underlying bone
  • May cause bone cyst formation, loss of bone and cartilage
  • Consists of CD68+ histiocytes with osteoclastic giant cell differentiation, may be hyperplastic, not neoplastic (Hum Pathol 2003;34:65)
  • Locally aggressive; may recur but only rarely has malignant behavior (Am J Surg Pathol 1997;21:153)
Case reports
Clinical images

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Stained synovium

Knee arthroscopy

Gross description
  • Focal or diffuse; brown yellow spongy tissue with variable color and firm nodular consistency
Gross images

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Brownish synovium

Microscopic (histologic) description
  • Hyperplastic synovium with papillary projections composed of foamy cells and hemosiderin containing macrophages
  • Also large clefts, pseudoglandular or alveolar spaces lined by synovial cells, multinucleated (10 - 70 nuclei) giant cells, epithelioid cells
  • Abundant collagen may be present but lymphocytes and plasma cells are sparse
  • No / rare mitotic figures
  • Malignant if nodular and solid invasive growth pattern are coupled with large round or oval cells with large nuclei, prominent nucleoli, necrotic areas, atypical mitotic figures
Microscopic (histologic) images

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Pseudoglandular or cleft-like spaces

Proliferation of polygonal cells

Multinucleated giant cells

Hemosiderin laden macrophages

Hemosiderin laden and lipid laden macrophages

Lipid laden macrophages

Malignant cases

Hemosiderin deposits, foamy histiocytes and giant cells

Virtual slides

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48 year old woman with synovial polyp

54 year old man with tissue from knee joint

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

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Positive stains
Molecular / cytogenetics description
Molecular / cytogenetics images

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FISH: trisomy 5 and 7

Differential diagnosis
  • Fibrosarcoma
  • Hemosiderotic synovitis: associated with hemophilia and intraarticular bleeding, no mononuclear or giant cell nodular cellular proliferation, hemosiderin primarily in synovial lining cells
  • Synovial sarcoma
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