Introduction:
Also known as localized nodular tenosynovitis
Most often on the volar aspect (flexor tendon) of fingers, close to distal joints
Pathologically identical to PVNS
In close contact with tendon
Can cause bone erosions
Malignant changes are rare
Clinical features:
Soft-tissue swelling and pain
Treatment and prognosis:
Surgery. But radical excision with negative margin is not indicated
Recurrence 10% to 20%
Ultrasound:
Uniformly hypoechoic, may be heterogenous. Posterior enhancement is not common
In contact/ close relation with a tendon or evn may be encased. But usually does not move with tendon, because the tumor arises from sheath, not from tendon itself
usually no cystic component/ hyperechogenicity/ calcification
Bone erosions may be diagnosed
Vascular on Doppler
Differential: ganglion - usually cystic, unless ruptured
References:
Middleton WD et al. Giant Cell Tumors of the Tendon Sheath: Analysis of Sonographic Findings. AJR 2004; 183:337-339
