Giant Cell Tumor of Tendon Sheath

David R. Lucas, MD

Key Facts

Terminology

Localized tenosynovial giant cell tumor, localized PVNS, nodular tenosynovitis

Etiology/Pathogenesis

Balanced translocation involving 1p13 (CSF1 gene) in many tumors
Arises from tendon sheath, intraarticular site, or bursa

Clinical Issues

2nd most common tumor of hand
Any age; peak 3rd-4th decade
Digits (85%)
Large joints (10%)
Intraarticular tumors called localized PVNS
Benign but recurs locally (around 20%)
Rarely involves overlying skin

Macroscopic Features

Average size: 1.1 cm (range: 0.5-6 cm)
Well demarcated
Multinodular with fibrous septa

Microscopic Pathology

Polymorphous population of stromal cells, macrophages, and osteoclast-like giant cells
Stromal fibrosis and hemosiderin deposits
Mitotic rate: 1-20 mitoses per 10 high-power fields (average: 5/10)

Top Differential Diagnoses

Dermatofibroma
Giant cell tumor of soft tissue
Diffuse-type tenosynovial giant cell tumor/PVNS

Giant cell tumor of tendon sheath presents as a painless, slow-growing mass that arises from a tendon sheath, most often on the volar aspect of a finger

. Secondary skin involvement is rare.

GCTTS has a mixture of mononuclear stromal cells, multinucleated giant cells

, and macrophages, including xanthoma cells

. Stromal fibrosis

and hemosiderin deposits

are very common.

TERMINOLOGY

Abbreviations

Giant cell tumor of tendon sheath (GCTTS)

Synonyms

Localized tenosynovial giant cell tumor, localized pigmented villonodular synovitis (PVNS), nodular tenosynovitis

Definitions

Benign soft tissue tumor of synovial origin
- Polymorphous population of neoplastic stromal cells, macrophages, and osteoclast-like giant cells
- Well circumscribed, noninvasive

ETIOLOGY/PATHOGENESIS

Histogenesis

Neoplastic growth
- Balanced translocation involving 1p13 (CSF1 gene) in many tumors
  - CSF1 overexpression by neoplastic stromal cells
  - Recruitment and activation of intratumoral macrophages by CSF1R activation

CLINICAL ISSUES

Epidemiology

Incidence
- 2nd most common tumor of hand
Age
- Any age; peak 3rd-4th decade
Gender
- Women outnumber men 2:1

Site

Digits (85%)
- Especially fingers (75%)
- Tendon sheath (usually volar) or interphalangeal joint
Large joints (10%)
- Ankle, knee, wrist, elbow
- Bursa
- Intraarticular tumors called localized PVNS
Skin secondarily involved in < 5% of cases

Presentation

Painless mass
Slow growing
Uncommon findings: Triggering, carpal and ulnar tunnel syndromes

Treatment

Surgical approaches
- Complete local excision

Prognosis

Benign, but recurs locally (around 20%)
Risk factors for recurrence: Degenerative joint disease, distal phalanx, interphalangeal joint of thumb, osseous erosion

IMAGE FINDINGS

Radiographic Findings